CN116617355A - Application of LTX-315 polypeptide in preparation of antibacterial infection resisting drugs - Google Patents
Application of LTX-315 polypeptide in preparation of antibacterial infection resisting drugs Download PDFInfo
- Publication number
- CN116617355A CN116617355A CN202310502310.2A CN202310502310A CN116617355A CN 116617355 A CN116617355 A CN 116617355A CN 202310502310 A CN202310502310 A CN 202310502310A CN 116617355 A CN116617355 A CN 116617355A
- Authority
- CN
- China
- Prior art keywords
- ltx
- polypeptide
- carbapenem
- resistant
- escherichia coli
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 108010029554 LTX-315 Proteins 0.000 title claims abstract description 160
- 239000003814 drug Substances 0.000 title claims abstract description 31
- 230000000844 anti-bacterial effect Effects 0.000 title claims abstract description 27
- 229940079593 drug Drugs 0.000 title claims abstract description 17
- 208000015181 infectious disease Diseases 0.000 title claims abstract description 13
- 238000002360 preparation method Methods 0.000 title claims description 14
- YZBQHRLRFGPBSL-RXMQYKEDSA-N carbapenem Chemical compound C1C=CN2C(=O)C[C@H]21 YZBQHRLRFGPBSL-RXMQYKEDSA-N 0.000 claims abstract description 54
- 230000001580 bacterial effect Effects 0.000 claims abstract description 49
- 241000588724 Escherichia coli Species 0.000 claims abstract description 47
- 241000588626 Acinetobacter baumannii Species 0.000 claims abstract description 46
- 241000894006 Bacteria Species 0.000 claims abstract description 43
- 239000003242 anti bacterial agent Substances 0.000 claims abstract description 38
- 230000012010 growth Effects 0.000 claims abstract description 34
- 229940088710 antibiotic agent Drugs 0.000 claims abstract description 30
- 230000000694 effects Effects 0.000 claims abstract description 29
- 229930186147 Cephalosporin Natural products 0.000 claims abstract description 25
- 229940124587 cephalosporin Drugs 0.000 claims abstract description 25
- 150000001780 cephalosporins Chemical class 0.000 claims abstract description 25
- 230000002401 inhibitory effect Effects 0.000 claims abstract description 17
- 241000192125 Firmicutes Species 0.000 claims abstract description 14
- 208000035143 Bacterial infection Diseases 0.000 claims abstract description 10
- 208000022362 bacterial infectious disease Diseases 0.000 claims abstract description 10
- GGAKLYWEFZCVIT-TVEKFXMRSA-N (2S)-2,6-diamino-N-[(2S)-6-amino-1-[[(2S)-1-[[(2S)-1-[[(2S)-6-amino-1-[[(2S)-6-amino-1-[[(2S)-1-[[(2S)-1-[[(2S)-1,6-diamino-1-oxohexan-2-yl]amino]-1-oxo-3,3-diphenylpropan-2-yl]amino]-3-(1H-indol-3-yl)-1-oxopropan-2-yl]amino]-1-oxohexan-2-yl]amino]-1-oxohexan-2-yl]amino]-3-(1H-indol-3-yl)-1-oxopropan-2-yl]amino]-3-(1H-indol-3-yl)-1-oxopropan-2-yl]amino]-1-oxohexan-2-yl]hexanamide Chemical group C=1C=CC=CC=1C([C@H](NC(=O)[C@H](CC=1C2=CC=CC=C2NC=1)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CC=1C2=CC=CC=C2NC=1)NC(=O)[C@H](CC=1C2=CC=CC=C2NC=1)NC(=O)[C@H](CCCCN)NC(=O)[C@@H](N)CCCCN)C(=O)N[C@@H](CCCCN)C(N)=O)C1=CC=CC=C1 GGAKLYWEFZCVIT-TVEKFXMRSA-N 0.000 claims abstract description 9
- 230000032770 biofilm formation Effects 0.000 claims abstract description 9
- 241000191967 Staphylococcus aureus Species 0.000 claims description 34
- 238000011282 treatment Methods 0.000 claims description 21
- 239000011248 coating agent Substances 0.000 claims description 14
- 238000000576 coating method Methods 0.000 claims description 14
- 241000589517 Pseudomonas aeruginosa Species 0.000 claims description 11
- 206010059866 Drug resistance Diseases 0.000 claims description 10
- 241000191963 Staphylococcus epidermidis Species 0.000 claims description 10
- 230000002441 reversible effect Effects 0.000 claims description 9
- 230000005764 inhibitory process Effects 0.000 claims description 6
- 241000588747 Klebsiella pneumoniae Species 0.000 claims description 5
- 241000194031 Enterococcus faecium Species 0.000 claims description 4
- 239000007924 injection Substances 0.000 claims description 4
- 238000002347 injection Methods 0.000 claims description 4
- 239000002775 capsule Substances 0.000 claims description 3
- 239000000839 emulsion Substances 0.000 claims description 3
- 239000008187 granular material Substances 0.000 claims description 3
- 239000006187 pill Substances 0.000 claims description 3
- 239000007921 spray Substances 0.000 claims description 3
- 239000003826 tablet Substances 0.000 claims description 3
- 241000194032 Enterococcus faecalis Species 0.000 claims description 2
- 241000193998 Streptococcus pneumoniae Species 0.000 claims description 2
- 229940032049 enterococcus faecalis Drugs 0.000 claims description 2
- 229940031000 streptococcus pneumoniae Drugs 0.000 claims description 2
- 239000000375 suspending agent Substances 0.000 claims description 2
- 229960004755 ceftriaxone Drugs 0.000 abstract description 29
- VAAUVRVFOQPIGI-SPQHTLEESA-N ceftriaxone Chemical compound S([C@@H]1[C@@H](C(N1C=1C(O)=O)=O)NC(=O)\C(=N/OC)C=2N=C(N)SC=2)CC=1CSC1=NC(=O)C(=O)NN1C VAAUVRVFOQPIGI-SPQHTLEESA-N 0.000 abstract description 29
- 210000004072 lung Anatomy 0.000 abstract description 5
- 230000002829 reductive effect Effects 0.000 abstract description 5
- 230000002195 synergetic effect Effects 0.000 abstract description 5
- 241001465754 Metazoa Species 0.000 abstract description 3
- 210000004027 cell Anatomy 0.000 description 13
- 210000000170 cell membrane Anatomy 0.000 description 13
- 239000007788 liquid Substances 0.000 description 12
- 239000001963 growth medium Substances 0.000 description 11
- 230000001954 sterilising effect Effects 0.000 description 11
- 238000011534 incubation Methods 0.000 description 10
- 230000006872 improvement Effects 0.000 description 9
- 241000589291 Acinetobacter Species 0.000 description 8
- 206010028980 Neoplasm Diseases 0.000 description 8
- ATBOMIWRCZXYSZ-XZBBILGWSA-N [1-[2,3-dihydroxypropoxy(hydroxy)phosphoryl]oxy-3-hexadecanoyloxypropan-2-yl] (9e,12e)-octadeca-9,12-dienoate Chemical compound CCCCCCCCCCCCCCCC(=O)OCC(COP(O)(=O)OCC(O)CO)OC(=O)CCCCCCC\C=C\C\C=C\CCCCC ATBOMIWRCZXYSZ-XZBBILGWSA-N 0.000 description 8
- AWUCVROLDVIAJX-UHFFFAOYSA-N alpha-glycerophosphate Natural products OCC(O)COP(O)(O)=O AWUCVROLDVIAJX-UHFFFAOYSA-N 0.000 description 8
- 238000004458 analytical method Methods 0.000 description 8
- 231100000135 cytotoxicity Toxicity 0.000 description 8
- 230000003013 cytotoxicity Effects 0.000 description 8
- ZGSPNIOCEDOHGS-UHFFFAOYSA-L disodium [3-[2,3-di(octadeca-9,12-dienoyloxy)propoxy-oxidophosphoryl]oxy-2-hydroxypropyl] 2,3-di(octadeca-9,12-dienoyloxy)propyl phosphate Chemical compound [Na+].[Na+].CCCCCC=CCC=CCCCCCCCC(=O)OCC(OC(=O)CCCCCCCC=CCC=CCCCCC)COP([O-])(=O)OCC(O)COP([O-])(=O)OCC(OC(=O)CCCCCCCC=CCC=CCCCCC)COC(=O)CCCCCCCC=CCC=CCCCCC ZGSPNIOCEDOHGS-UHFFFAOYSA-L 0.000 description 8
- 239000007850 fluorescent dye Substances 0.000 description 8
- 238000004659 sterilization and disinfection Methods 0.000 description 8
- 238000002474 experimental method Methods 0.000 description 7
- 239000012528 membrane Substances 0.000 description 7
- 244000052769 pathogen Species 0.000 description 7
- XJMOSONTPMZWPB-UHFFFAOYSA-M propidium iodide Chemical compound [I-].[I-].C12=CC(N)=CC=C2C2=CC=C(N)C=C2[N+](CCC[N+](C)(CC)CC)=C1C1=CC=CC=C1 XJMOSONTPMZWPB-UHFFFAOYSA-M 0.000 description 7
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 6
- 108010059993 Vancomycin Proteins 0.000 description 6
- 230000003385 bacteriostatic effect Effects 0.000 description 6
- 230000006378 damage Effects 0.000 description 6
- 210000001616 monocyte Anatomy 0.000 description 6
- 229960003165 vancomycin Drugs 0.000 description 6
- MYPYJXKWCTUITO-LYRMYLQWSA-N vancomycin Chemical compound O([C@@H]1[C@@H](O)[C@H](O)[C@@H](CO)O[C@H]1OC1=C2C=C3C=C1OC1=CC=C(C=C1Cl)[C@@H](O)[C@H](C(N[C@@H](CC(N)=O)C(=O)N[C@H]3C(=O)N[C@H]1C(=O)N[C@H](C(N[C@@H](C3=CC(O)=CC(O)=C3C=3C(O)=CC=C1C=3)C(O)=O)=O)[C@H](O)C1=CC=C(C(=C1)Cl)O2)=O)NC(=O)[C@@H](CC(C)C)NC)[C@H]1C[C@](C)(N)[C@H](O)[C@H](C)O1 MYPYJXKWCTUITO-LYRMYLQWSA-N 0.000 description 6
- MYPYJXKWCTUITO-UHFFFAOYSA-N vancomycin Natural products O1C(C(=C2)Cl)=CC=C2C(O)C(C(NC(C2=CC(O)=CC(O)=C2C=2C(O)=CC=C3C=2)C(O)=O)=O)NC(=O)C3NC(=O)C2NC(=O)C(CC(N)=O)NC(=O)C(NC(=O)C(CC(C)C)NC)C(O)C(C=C3Cl)=CC=C3OC3=CC2=CC1=C3OC1OC(CO)C(O)C(O)C1OC1CC(C)(N)C(O)C(C)O1 MYPYJXKWCTUITO-UHFFFAOYSA-N 0.000 description 6
- 210000003556 vascular endothelial cell Anatomy 0.000 description 6
- JZNWSCPGTDBMEW-UHFFFAOYSA-N Glycerophosphorylethanolamin Natural products NCCOP(O)(=O)OCC(O)CO JZNWSCPGTDBMEW-UHFFFAOYSA-N 0.000 description 5
- GSDSWSVVBLHKDQ-JTQLQIEISA-N Levofloxacin Chemical compound C([C@@H](N1C2=C(C(C(C(O)=O)=C1)=O)C=C1F)C)OC2=C1N1CCN(C)CC1 GSDSWSVVBLHKDQ-JTQLQIEISA-N 0.000 description 5
- RJQXTJLFIWVMTO-TYNCELHUSA-N Methicillin Chemical compound COC1=CC=CC(OC)=C1C(=O)N[C@@H]1C(=O)N2[C@@H](C(O)=O)C(C)(C)S[C@@H]21 RJQXTJLFIWVMTO-TYNCELHUSA-N 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 5
- 201000011510 cancer Diseases 0.000 description 5
- 210000001985 kidney epithelial cell Anatomy 0.000 description 5
- 229960003376 levofloxacin Drugs 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 229960003085 meticillin Drugs 0.000 description 5
- 230000035699 permeability Effects 0.000 description 5
- 150000008104 phosphatidylethanolamines Chemical class 0.000 description 5
- 150000003904 phospholipids Chemical class 0.000 description 5
- 241000699670 Mus sp. Species 0.000 description 4
- 238000002835 absorbance Methods 0.000 description 4
- 230000002924 anti-infective effect Effects 0.000 description 4
- 231100000673 dose–response relationship Toxicity 0.000 description 4
- 238000011160 research Methods 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 241001360526 Escherichia coli ATCC 25922 Species 0.000 description 3
- 241000699666 Mus <mouse, genus> Species 0.000 description 3
- 229960000484 ceftazidime Drugs 0.000 description 3
- NMVPEQXCMGEDNH-TZVUEUGBSA-N ceftazidime pentahydrate Chemical compound O.O.O.O.O.S([C@@H]1[C@@H](C(N1C=1C([O-])=O)=O)NC(=O)\C(=N/OC(C)(C)C(O)=O)C=2N=C(N)SC=2)CC=1C[N+]1=CC=CC=C1 NMVPEQXCMGEDNH-TZVUEUGBSA-N 0.000 description 3
- 238000013211 curve analysis Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 238000007865 diluting Methods 0.000 description 3
- 239000002609 medium Substances 0.000 description 3
- 238000012544 monitoring process Methods 0.000 description 3
- 239000013642 negative control Substances 0.000 description 3
- 239000002504 physiological saline solution Substances 0.000 description 3
- 239000013641 positive control Substances 0.000 description 3
- 108090000765 processed proteins & peptides Proteins 0.000 description 3
- 238000012827 research and development Methods 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 231100000820 toxicity test Toxicity 0.000 description 3
- FZNINMHMRBYDPR-UHFFFAOYSA-N 1-[4-(4-bromophenyl)butyl]imidazole Chemical compound C1=CC(Br)=CC=C1CCCCN1C=NC=C1 FZNINMHMRBYDPR-UHFFFAOYSA-N 0.000 description 2
- JEGUERWMMMQFJV-UHFFFAOYSA-N 5-methylbenzo[g][1,3]benzoxazol-2-amine Chemical compound C12=CC=CC=C2C(C)=CC2=C1OC(N)=N2 JEGUERWMMMQFJV-UHFFFAOYSA-N 0.000 description 2
- 241000588914 Enterobacter Species 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 2
- 235000010469 Glycine max Nutrition 0.000 description 2
- 244000068988 Glycine max Species 0.000 description 2
- 208000032376 Lung infection Diseases 0.000 description 2
- 108010087230 Sincalide Proteins 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 210000001744 T-lymphocyte Anatomy 0.000 description 2
- 150000001348 alkyl chlorides Chemical class 0.000 description 2
- 230000003698 anagen phase Effects 0.000 description 2
- 230000005975 antitumor immune response Effects 0.000 description 2
- HVFLCNVBZFFHBT-ZKDACBOMSA-N cefepime Chemical compound S([C@@H]1[C@@H](C(N1C=1C([O-])=O)=O)NC(=O)\C(=N/OC)C=2N=C(N)SC=2)CC=1C[N+]1(C)CCCC1 HVFLCNVBZFFHBT-ZKDACBOMSA-N 0.000 description 2
- 229960002100 cefepime Drugs 0.000 description 2
- 238000010609 cell counting kit-8 assay Methods 0.000 description 2
- 239000006285 cell suspension Substances 0.000 description 2
- 238000005119 centrifugation Methods 0.000 description 2
- MYPYJXKWCTUITO-KIIOPKALSA-N chembl3301825 Chemical compound O([C@@H]1[C@@H](O)[C@H](O)[C@@H](CO)O[C@H]1OC1=C2C=C3C=C1OC1=CC=C(C=C1Cl)[C@@H](O)[C@H](C(N[C@@H](CC(N)=O)C(=O)N[C@H]3C(=O)N[C@H]1C(=O)N[C@H](C(N[C@H](C3=CC(O)=CC(O)=C3C=3C(O)=CC=C1C=3)C(O)=O)=O)[C@H](O)C1=CC=C(C(=C1)Cl)O2)=O)NC(=O)[C@@H](CC(C)C)NC)[C@H]1C[C@](C)(N)C(O)[C@H](C)O1 MYPYJXKWCTUITO-KIIOPKALSA-N 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 230000001332 colony forming effect Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000012228 culture supernatant Substances 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 239000000975 dye Substances 0.000 description 2
- 210000002919 epithelial cell Anatomy 0.000 description 2
- 239000008103 glucose Substances 0.000 description 2
- 238000009169 immunotherapy Methods 0.000 description 2
- 230000002601 intratumoral effect Effects 0.000 description 2
- 231100001231 less toxic Toxicity 0.000 description 2
- 238000000816 matrix-assisted laser desorption--ionisation Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 201000001441 melanoma Diseases 0.000 description 2
- 238000003266 membrane potential measurement method Methods 0.000 description 2
- VMGAPWLDMVPYIA-HIDZBRGKSA-N n'-amino-n-iminomethanimidamide Chemical compound N\N=C\N=N VMGAPWLDMVPYIA-HIDZBRGKSA-N 0.000 description 2
- 102000039446 nucleic acids Human genes 0.000 description 2
- 108020004707 nucleic acids Proteins 0.000 description 2
- 150000007523 nucleic acids Chemical class 0.000 description 2
- 230000000174 oncolytic effect Effects 0.000 description 2
- 230000036961 partial effect Effects 0.000 description 2
- 230000001717 pathogenic effect Effects 0.000 description 2
- 239000008194 pharmaceutical composition Substances 0.000 description 2
- 230000035755 proliferation Effects 0.000 description 2
- 230000002685 pulmonary effect Effects 0.000 description 2
- BOLDJAUMGUJJKM-LSDHHAIUSA-N renifolin D Natural products CC(=C)[C@@H]1Cc2c(O)c(O)ccc2[C@H]1CC(=O)c3ccc(O)cc3O BOLDJAUMGUJJKM-LSDHHAIUSA-N 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- IZTQOLKUZKXIRV-YRVFCXMDSA-N sincalide Chemical compound C([C@@H](C(=O)N[C@@H](CCSC)C(=O)NCC(=O)N[C@@H](CC=1C2=CC=CC=C2NC=1)C(=O)N[C@@H](CCSC)C(=O)N[C@@H](CC(O)=O)C(=O)N[C@@H](CC=1C=CC=CC=1)C(N)=O)NC(=O)[C@@H](N)CC(O)=O)C1=CC=C(OS(O)(=O)=O)C=C1 IZTQOLKUZKXIRV-YRVFCXMDSA-N 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 238000002560 therapeutic procedure Methods 0.000 description 2
- 239000012137 tryptone Substances 0.000 description 2
- 210000004881 tumor cell Anatomy 0.000 description 2
- MLBZLJCMHFCTQM-UHFFFAOYSA-N (2-methylphenyl)-diphenylphosphane Chemical compound CC1=CC=CC=C1P(C=1C=CC=CC=1)C1=CC=CC=C1 MLBZLJCMHFCTQM-UHFFFAOYSA-N 0.000 description 1
- NHBKXEKEPDILRR-UHFFFAOYSA-N 2,3-bis(butanoylsulfanyl)propyl butanoate Chemical compound CCCC(=O)OCC(SC(=O)CCC)CSC(=O)CCC NHBKXEKEPDILRR-UHFFFAOYSA-N 0.000 description 1
- JKMHFZQWWAIEOD-UHFFFAOYSA-N 2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid Chemical compound OCC[NH+]1CCN(CCS([O-])(=O)=O)CC1 JKMHFZQWWAIEOD-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-M Acrylate Chemical compound [O-]C(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-M 0.000 description 1
- 102000044503 Antimicrobial Peptides Human genes 0.000 description 1
- 108700042778 Antimicrobial Peptides Proteins 0.000 description 1
- 102000004506 Blood Proteins Human genes 0.000 description 1
- 108010017384 Blood Proteins Proteins 0.000 description 1
- 108020005199 Dehydrogenases Proteins 0.000 description 1
- 108090000204 Dipeptidase 1 Proteins 0.000 description 1
- 102000004190 Enzymes Human genes 0.000 description 1
- 108090000790 Enzymes Proteins 0.000 description 1
- 235000009161 Espostoa lanata Nutrition 0.000 description 1
- 240000001624 Espostoa lanata Species 0.000 description 1
- 201000008808 Fibrosarcoma Diseases 0.000 description 1
- SXRSQZLOMIGNAQ-UHFFFAOYSA-N Glutaraldehyde Chemical compound O=CCCCC=O SXRSQZLOMIGNAQ-UHFFFAOYSA-N 0.000 description 1
- 239000007995 HEPES buffer Substances 0.000 description 1
- 241000282412 Homo Species 0.000 description 1
- PIWKPBJCKXDKJR-UHFFFAOYSA-N Isoflurane Chemical compound FC(F)OC(Cl)C(F)(F)F PIWKPBJCKXDKJR-UHFFFAOYSA-N 0.000 description 1
- 206010048723 Multiple-drug resistance Diseases 0.000 description 1
- 241000233805 Phoenix Species 0.000 description 1
- 206010039491 Sarcoma Diseases 0.000 description 1
- 102100029469 WD repeat and HMG-box DNA-binding protein 1 Human genes 0.000 description 1
- 101710097421 WD repeat and HMG-box DNA-binding protein 1 Proteins 0.000 description 1
- 208000027418 Wounds and injury Diseases 0.000 description 1
- 239000000980 acid dye Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000003044 adaptive effect Effects 0.000 description 1
- 150000001413 amino acids Chemical group 0.000 description 1
- 230000000845 anti-microbial effect Effects 0.000 description 1
- 230000005809 anti-tumor immunity Effects 0.000 description 1
- 229940124350 antibacterial drug Drugs 0.000 description 1
- 239000004599 antimicrobial Substances 0.000 description 1
- 239000002246 antineoplastic agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 1
- 102000006635 beta-lactamase Human genes 0.000 description 1
- 230000003115 biocidal effect Effects 0.000 description 1
- 238000002815 broth microdilution Methods 0.000 description 1
- 125000002091 cationic group Chemical group 0.000 description 1
- 230000001364 causal effect Effects 0.000 description 1
- 230000004663 cell proliferation Effects 0.000 description 1
- 230000003833 cell viability Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 229940000425 combination drug Drugs 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000012258 culturing Methods 0.000 description 1
- 210000000805 cytoplasm Anatomy 0.000 description 1
- 231100000433 cytotoxic Toxicity 0.000 description 1
- 230000001472 cytotoxic effect Effects 0.000 description 1
- 238000002784 cytotoxicity assay Methods 0.000 description 1
- 231100000263 cytotoxicity test Toxicity 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- -1 diBAC4 (3) Substances 0.000 description 1
- 230000000459 effect on growth Effects 0.000 description 1
- 230000000431 effect on proliferation Effects 0.000 description 1
- 238000001493 electron microscopy Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 239000012737 fresh medium Substances 0.000 description 1
- 238000003205 genotyping method Methods 0.000 description 1
- 230000009036 growth inhibition Effects 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 230000005802 health problem Effects 0.000 description 1
- 210000005260 human cell Anatomy 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 230000028993 immune response Effects 0.000 description 1
- 230000036039 immunity Effects 0.000 description 1
- 230000005847 immunogenicity Effects 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 238000011081 inoculation Methods 0.000 description 1
- 239000002054 inoculum Substances 0.000 description 1
- 239000007928 intraperitoneal injection Substances 0.000 description 1
- 229960002725 isoflurane Drugs 0.000 description 1
- 231100000053 low toxicity Toxicity 0.000 description 1
- 238000004949 mass spectrometry Methods 0.000 description 1
- 230000002906 microbiologic effect Effects 0.000 description 1
- 238000005142 microbroth dilution method Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 210000003470 mitochondria Anatomy 0.000 description 1
- 230000004660 morphological change Effects 0.000 description 1
- 238000010172 mouse model Methods 0.000 description 1
- 229930014626 natural product Natural products 0.000 description 1
- 239000008363 phosphate buffer Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 238000012342 propidium iodide staining Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 238000011552 rat model Methods 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 210000002345 respiratory system Anatomy 0.000 description 1
- 238000013207 serial dilution Methods 0.000 description 1
- VSIVTUIKYVGDCX-UHFFFAOYSA-M sodium;4-[2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)tetrazol-2-ium-5-yl]benzene-1,3-disulfonate Chemical compound [Na+].COC1=CC([N+]([O-])=O)=CC=C1[N+]1=NC(C=2C(=CC(=CC=2)S([O-])(=O)=O)S([O-])(=O)=O)=NN1C1=CC=C([N+]([O-])=O)C=C1 VSIVTUIKYVGDCX-UHFFFAOYSA-M 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000010186 staining Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000009885 systemic effect Effects 0.000 description 1
- 230000008685 targeting Effects 0.000 description 1
- 230000036962 time dependent Effects 0.000 description 1
- 238000001269 time-of-flight mass spectrometry Methods 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 238000004627 transmission electron microscopy Methods 0.000 description 1
- 238000011269 treatment regimen Methods 0.000 description 1
- CMPGARWFYBADJI-UHFFFAOYSA-L tungstic acid Chemical compound O[W](O)(=O)=O CMPGARWFYBADJI-UHFFFAOYSA-L 0.000 description 1
- 210000005166 vasculature Anatomy 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K38/00—Medicinal preparations containing peptides
- A61K38/04—Peptides having up to 20 amino acids in a fully defined sequence; Derivatives thereof
- A61K38/08—Peptides having 5 to 11 amino acids
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N37/00—Biocides, pest repellants or attractants, or plant growth regulators containing organic compounds containing a carbon atom having three bonds to hetero atoms with at the most two bonds to halogen, e.g. carboxylic acids
- A01N37/44—Biocides, pest repellants or attractants, or plant growth regulators containing organic compounds containing a carbon atom having three bonds to hetero atoms with at the most two bonds to halogen, e.g. carboxylic acids containing at least one carboxylic group or a thio analogue, or a derivative thereof, and a nitrogen atom attached to the same carbon skeleton by a single or double bond, this nitrogen atom not being a member of a derivative or of a thio analogue of a carboxylic group, e.g. amino-carboxylic acids
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01P—BIOCIDAL, PEST REPELLANT, PEST ATTRACTANT OR PLANT GROWTH REGULATORY ACTIVITY OF CHEMICAL COMPOUNDS OR PREPARATIONS
- A01P1/00—Disinfectants; Antimicrobial compounds or mixtures thereof
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L31/00—Materials for other surgical articles, e.g. stents, stent-grafts, shunts, surgical drapes, guide wires, materials for adhesion prevention, occluding devices, surgical gloves, tissue fixation devices
- A61L31/08—Materials for coatings
- A61L31/10—Macromolecular materials
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L31/00—Materials for other surgical articles, e.g. stents, stent-grafts, shunts, surgical drapes, guide wires, materials for adhesion prevention, occluding devices, surgical gloves, tissue fixation devices
- A61L31/14—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
- A61L31/16—Biologically active materials, e.g. therapeutic substances
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
- A61P31/00—Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
- A61P31/04—Antibacterial agents
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L2300/00—Biologically active materials used in bandages, wound dressings, absorbent pads or medical devices
- A61L2300/20—Biologically active materials used in bandages, wound dressings, absorbent pads or medical devices containing or releasing organic materials
- A61L2300/252—Polypeptides, proteins, e.g. glycoproteins, lipoproteins, cytokines
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L2300/00—Biologically active materials used in bandages, wound dressings, absorbent pads or medical devices
- A61L2300/40—Biologically active materials used in bandages, wound dressings, absorbent pads or medical devices characterised by a specific therapeutic activity or mode of action
- A61L2300/404—Biocides, antimicrobial agents, antiseptic agents
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L2300/00—Biologically active materials used in bandages, wound dressings, absorbent pads or medical devices
- A61L2300/60—Biologically active materials used in bandages, wound dressings, absorbent pads or medical devices characterised by a special physical form
- A61L2300/606—Coatings
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
- Y02A50/30—Against vector-borne diseases, e.g. mosquito-borne, fly-borne, tick-borne or waterborne diseases whose impact is exacerbated by climate change
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Veterinary Medicine (AREA)
- Public Health (AREA)
- Animal Behavior & Ethology (AREA)
- Epidemiology (AREA)
- Medicinal Chemistry (AREA)
- Surgery (AREA)
- Environmental Sciences (AREA)
- Pharmacology & Pharmacy (AREA)
- Heart & Thoracic Surgery (AREA)
- Pest Control & Pesticides (AREA)
- Zoology (AREA)
- Vascular Medicine (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Wood Science & Technology (AREA)
- Plant Pathology (AREA)
- Oncology (AREA)
- Agronomy & Crop Science (AREA)
- Organic Chemistry (AREA)
- Dentistry (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Communicable Diseases (AREA)
- Proteomics, Peptides & Aminoacids (AREA)
- Immunology (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Gastroenterology & Hepatology (AREA)
- Biomedical Technology (AREA)
- Molecular Biology (AREA)
- Medicines That Contain Protein Lipid Enzymes And Other Medicines (AREA)
Abstract
The invention provides application of LTX-315 polypeptide in preparing anti-bacterial infection medicines, wherein the CAS number of the LTX-315 polypeptide is 1345407-05-7; the LTX-315 polypeptide has the effects of inhibiting bacterial growth and biofilm formation. The technical scheme of the invention discloses a novel medical application of LTX-315 polypeptide, the LTX-315 polypeptide has better antibacterial activity on various gram-positive bacteria and gram-negative bacteria clinical isolates, and has synergistic antibacterial activity with cephalosporin antibiotics, so that carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli are re-sensitized to cephalosporin antibiotics, and the bacterial load of the lungs of animals infected by carbapenem-resistant acinetobacter baumannii can be obviously reduced by using the LTX-315 polypeptide and ceftriaxone in combination in animal infection models.
Description
Technical Field
The invention belongs to the technical field of medicines, and particularly relates to application of LTX-315 polypeptide in preparation of antibacterial infection medicines.
Background
Bacterial infection is one of the major health problems facing humans. However, with the widespread use of antibiotics, drug-resistant bacterial infections have become a major challenge in clinical treatment. It is counted that over 700 tens of thousands of people die each year from drug-resistant bacteria infection. The ESKAPE pathogens are important clinical pathogens of current medical concern, including enterococcus faecium (Enterococcus faecium), staphylococcus aureus (Staphylococcus aureus), klebsiella pneumoniae (Klebsiella pneumoniae), acinetobacter baumannii (Acinetobacter baumannii), pseudomonas aeruginosa (Pseudomonas aeruginosa), and enterobacter (Enterobacter species). Because of its increased resistance, traditional antibiotic treatment has not been effective in controlling these infections, and infections caused by ESKAPE pathogens often lead to long hospitalization and high mortality. These pathogens are widely available worldwide and have the property of multiple drug resistance, which constitutes a major threat to human health. Currently, the research and development of antibiotics has entered a bottleneck. The traditional mining method is difficult to meet the requirements of novel antibiotics with high efficiency, low toxicity and low side effects.
Therefore, there is a need to explore new research methods such as natural products, novel chemicals, and antimicrobial peptides. Research and development of novel antibiotics is imperative in solving the problem of ESKAPE pathogen infection. On this basis, related treatment strategies such as combination drug, pathogen genotyping and novel immunotherapy are also required to be further perfected, so that the treatment effect is improved and the mortality of patients is reduced. In summary, research on ESKAPE pathogens and development of antibiotics have become hot spots of concern in the current medical community. Only by developing more basic and clinical researches, more theoretical support can be provided for the innovative research and development of antibacterial drugs, and more accurate strategies can be provided for clinical treatment.
Disclosure of Invention
Aiming at the technical problems, the invention discloses application of an LTX-315 polypeptide in preparing an antibacterial infection medicament, which is a new medicament application of the LTX-315 polypeptide, experiments show that the LTX-315 polypeptide shows antibacterial activity and bactericidal activity on gram-positive bacteria including staphylococcus aureus, staphylococcus epidermidis and the like and various clinical isolates including Acinetobacter baumannii, escherichia coli, pseudomonas aeruginosa and the like, and can restore sensitivity of carbapenem-resistant Acinetobacter baumannii to cephalosporin antibiotics, thereby providing reference basis for development of antibacterial medicaments based on the LTX-315 polypeptide and combined medicament for drug-resistant bacteria.
In this regard, the invention adopts the following technical scheme:
the application of LTX-315 polypeptide in preparing anti-bacterial infection medicines, wherein the LTX-315 polypeptide has CAS number 1345407-05-7, and the LTX-315 polypeptide has the effects of inhibiting bacterial growth and biofilm formation.
The amino acid sequence of the LTX-315 polypeptide is H-Lys-Lys-Trp-Trp-Lys-Lys-Trp-Dip-Lys-NH2 (abbreviated as KWWKKWXK), and the structural formula is shown in the formula (1):
LTX-315 polypeptide is an artificially synthesized cationic 9 peptide, and is also called an oncolytic peptide because of its strong cytotoxicity to various mouse and human cancer cell lines. LTX-315 polypeptides can kill cancer cells by disrupting cell membranes and targeting mitochondria. In addition, LTX-315 polypeptide cytotoxicity against cancer is also associated with promotion of cancer immunity, including destruction of tumor vasculature and enhancement of immunogenicity of tumor cells, promotion of CD8 + T cell infiltration. Thus, the LTX-315 polypeptide is considered to be promising for cancer treatment, since it not only kills tumor cells, but also promotes anti-tumor immunity. LTX-315 polypeptide has relatively high plasma protein binding capacity and a human plasma half-life of 15 minutes. Based on these properties, LTX-315Polypeptides are being developed for intratumoral administration as new anticancer agents and are currently being evaluated clinically as the first oncolytic peptide-based local immunotherapy. Studies in a mouse model have shown that intratumoral injection of LTX-315 polypeptide in intradermally established B16F10 melanoma can completely regress most tumors. In addition, the cured animals can prevent B16F10 melanoma cells from invading again through immune response, which indicates that LTX-315 polypeptide treatment can induce adaptive anti-tumor immune response. LTX-315 polypeptide therapy can also resolve established mouse MCA205 sarcoma. LTX-315 polypeptide treatment reprograms the MCA205 tumor microenvironment, increasing cytotoxicity CD8 + Local abundance of T cells. Also, LTX-315 polypeptide therapy can successfully eliminate intradermally established rtms fibrosarcoma and elicit protective and systemic anti-tumor immune responses in the rat model. However, at present, no report is made about the antibacterial activity of LTX-315 polypeptide.
As a further improvement of the present invention, the bacteria include gram-positive bacteria and gram-negative bacteria, the gram-positive bacteria are at least one of staphylococcus aureus, enterococcus faecalis, enterococcus faecium, staphylococcus epidermidis or streptococcus pneumoniae, and the gram-negative bacteria are at least one of acinetobacter baumannii, klebsiella pneumoniae, escherichia coli and pseudomonas aeruginosa.
Through a great deal of experimental researches, the LTX-315 polypeptide has antibacterial activity on a plurality of gram-positive bacteria including staphylococcus aureus, staphylococcus epidermidis and the like, and clinical isolates of a plurality of gram-negative bacteria including acinetobacter baumannii, escherichia coli, pseudomonas aeruginosa and the like, and has more remarkable antibacterial activity than vancomycin. The results of electron microscopy and causal dye staining analysis show that the LTX-315 polypeptide can damage the integrity of bacteria, and the addition of bacterial membrane phospholipid components in a culture medium can reduce the bacteriostatic activity of the LTX-315 polypeptide in a dose-dependent manner, which indicates that the bacteriostatic activity of the LTX-315 polypeptide is targeted to damage bacterial plasma membranes. In addition, LTX-315 polypeptide can reverse the drug resistance of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli, so that the carbapenem-resistant escherichia coli is sensitive to cephalosporin antibiotics. In addition, LTX-315 polypeptide is less toxic to human cells and less toxic to proliferation of vascular endothelial cells HUEVC, the monocyte line j774a.1, and the human kidney epithelial cell line 293T. These results indicate that LTX-315 polypeptide has potential application value in clinical anti-bacterial infection treatment.
As a further improvement of the present invention, the concentration of LTX-315 polypeptide in the treatment system is not less than 2. Mu.g/mL. Further, the concentration of the LTX-315 polypeptide in the treatment system is 2-128 mug/mL.
As a further improvement of the present invention, the medicament is a pharmaceutical composition or formulation. Further, the medicine is injection, tablet, pill, capsule, suspending agent, granule, spray or emulsion.
As a further improvement of the present invention, the concentration of the LTX-315 polypeptide in the treatment system is not less than 2. Mu.g/mL.
As a further improvement of the present invention, the medicament is an injection, a tablet, a pill, a capsule, a suspension, a granule, a spray or an emulsion.
As a further improvement of the invention, the medicament also comprises cephalosporin antibiotics, and the LTX-315 polypeptide can reverse the drug resistance of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli, so that the carbapenem-resistant escherichia coli is sensitive to the cephalosporin antibiotics.
The invention also discloses application of the LTX-315 polypeptide in preparing a coating for inhibiting bacteria, the coating is used for the surface of a medical appliance, the CAS number of the LTX-315 polypeptide is 1345407-05-7, and the LTX-315 polypeptide has the effects of inhibiting bacterial growth and biofilm formation.
As a further improvement of the present invention, the concentration of the LTX-315 polypeptide in the coating is not less than 2. Mu.g/mL.
As a further improvement of the invention, the coating also comprises cephalosporin antibiotics, and the LTX-315 polypeptide can reverse the drug resistance of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli, so that the coating is sensitive to the cephalosporin antibiotics.
The invention also discloses application of the LTX-315 polypeptide in preparing an antibacterial agent, wherein the CAS number of the LTX-315 polypeptide is 1345407-05-7, and the LTX-315 polypeptide has the effects of inhibiting bacterial growth and biofilm formation.
As a further improvement of the invention, the antibacterial agent also comprises cephalosporin antibiotics, and the LTX-315 polypeptide can reverse the drug resistance of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli, so that the bacteria are sensitive to the cephalosporin antibiotics.
Compared with the prior art, the invention has the beneficial effects that:
the technical scheme of the invention discloses a novel medical application of LTX-315 polypeptide, wherein the LTX-315 polypeptide has better antibacterial activity on various gram-positive bacteria including staphylococcus aureus, staphylococcus epidermidis and the like, and various gram-negative bacteria including acinetobacter baumannii, escherichia coli, pseudomonas aeruginosa and the like, has more obvious inhibition effect on the gram-positive bacteria, has more obvious bactericidal activity than vancomycin, and can kill bacteria in a biological envelope. LTX-315 polypeptide has less toxicity to human vascular endothelial cells HUEVC, monocyte line J774a.1 and human kidney epithelial cell line 293T at the lowest inhibitory concentration (MIC) dose. These results suggest the possibility of treating a variety of drug-resistant bacterial infections with LTX-315 polypeptides. In addition, the LTX-315 polypeptide and the calcaneal cephalosporin antibiotics are combined to show a synergistic effect, and are suitable for clinical application. The LTX-315 polypeptide has potential application value in clinical antibacterial infection treatment.
Drawings
FIG. 1 shows growth curves of gram-positive bacteria including Acinetobacter baumannii and Escherichia coli after addition of LTX-315 polypeptide, wherein (a) to (f) are staphylococcus aureus CHS101 and YUSA145, acinetobacter baumannii AB2220 and AB2221, escherichia coli ECO2201 and ECO2221, respectively, and MIC in the figure represents the minimum inhibitory concentration.
FIG. 2 shows the analysis of the sterilization curves of LTX-315 polypeptide of the invention on methicillin-resistant staphylococcus aureus (MRSA) clinical strain YUSA145, carbapenem-resistant Acinetobacter baumannii clinical strain AB2221, and ultra-broad-spectrum beta-lactamase (ESBLs) producing escherichia coli ECO2201, wherein (a) is YUSA145, (b) is AB2221, (c) is ECO2201, MIC represents the minimum inhibitory concentration in the figure, vancomycin represents Vancomycin, and Levofloxacin represents Levofloxacin.
FIG. 3 shows the results of the analysis of the antimicrobial action mechanism of LTX-315 polypeptide according to the embodiment of the present invention, wherein (a) shows the effect of different concentrations of LTX-315 polypeptide on the permeability of clinical strain YUSA145 of staphylococcus aureus under the observation of a laser confocal microscope, (b) shows the effect of different concentrations of LTX-315 polypeptide on the permeability of clinical strain YUSA145 of staphylococcus aureus under the observation of a fluorescent dye Propidium Iodide (PI), (c) shows the effect of different concentrations of LTX-315 polypeptide on the membrane potential of clinical strain YUSA145 of staphylococcus aureus under the observation of a fluorescent dye DiBAC4 (3), (d) shows the effect of 4 XMIC LTX-315 polypeptide on the morphological change of clinical strain YUSA145 under the observation of a transmission electron microscope, (e) shows the effect of exogenous addition of different concentrations of phospholipid on the MIC of LTX-315 polypeptide, CL shows cardiolipin the figure, PG shows phosphatidylglycerol, and PE shows phosphatidylethanolamine.
FIG. 4 shows the results of the effect of LTX-315 polypeptide and Ceftriaxone (Ceftriaxone) on the growth curve of a clinical strain AB2220 of Acinetobacter carbapenem-Bowman, wherein (a) is the effect of different concentrations of LTX-315 polypeptide on the growth of AB2220, (b) is the effect of different concentrations of Ceftriaxone on the growth of AB2220, and (c) is the effect of 1/4 xMIC (8 μg/mL) of LTX-315 polypeptide and different concentrations of Ceftriaxone on the growth curve, and Ceftriaxone is represented in the figure.
FIG. 5 shows the analysis of the sterilizing curves of LTX-315 polypeptide and ceftriaxone on the plankton bacteria of the clinical strains AB2220 and AB2221 of Acinetobacter baumannii resistant to carbapenem, wherein (a) and (b) are respectively the analysis of the sterilizing activities of LTX-315 polypeptide and ceftriaxone on the plankton bacteria of AB2220 and AB2221, and ceftriaxone is represented in the figure.
FIG. 6 shows the results of cytotoxicity assays of LTX-315 polypeptide at different concentrations on human vascular endothelial cell HUEVC, monocyte line J774a.1 and human renal epithelial cell line 293T according to the examples of the present invention; in the figure, (a) shows the result of toxicity test for human kidney epithelial cell line 293T, (b) shows the result of toxicity test for monocyte line J774a.1, and (c) shows the result of toxicity test for human vascular endothelial cell HUEVC.
FIG. 7 is a graph showing the results of anti-infective effect of LTX-315 polypeptide combined with ceftriaxone on a clinical strain AB2220 lung infection of Acinetobacter carbapenem, wherein cfu represents colony forming units.
Detailed Description
Preferred embodiments of the present invention are described in further detail below.
Example 1
1.1 sources of Strain
The 62 gram-positive bacteria (including 20 MRSA,20 MSSA,22 Staphylococcus epidermidis) and 64 gram-negative bacteria (including 19 Acinetobacter baumannii, 20 Pseudomonas aeruginosa, and 25 Escherichia coli) used in this example were collected in different hospitalized patients in hospitals. All clinical strains were identified by the Phoenix 100 automated microbiological identification system, and all strains were re-identified after subculture using matrix assisted laser desorption ionization/time of flight mass spectrometry (MALDI-TOF-MS). Quality control strain staphylococcus aureus ATCC29213 was purchased from ATCC strain library.
1.2 major instrumentation and reagents
Micropipettes, phoenix-100 full-automatic bacterial identification/drug sensitivity system, full-automatic biological mass spectrometry detection system IVD MALDI Biotyper, full-automatic growth curve analyzer, CAMHB medium, TSB medium, HT7800 transmission electron microscope, laser confocal microscope FV3000.LTX-315 polypeptide, fluorescent dye Propidium Iodide (PI), diBAC4 (3), crystal violet, LIVE/DEAD BacLight TM Fluorescent dyes, glucose, cardiolipin, phosphatidylglycerol and phosphatidylethanolamine.
In the embodiment, a 96-well plate is adopted to perform an experiment of the influence of LTX-315 polypeptide on the growth of staphylococcus aureus and escherichia coli, and the specific steps are as follows:
taking overnight culture broth (Staphylococcus aureus ATCC29213 and Escherichia coli ATCC 25922), adjusting turbidity to 0.5 McGer. with turbidimetric cup (bacterial amount about 1.0-1.5X10) 8 cfu/mL). Diluting the bacterial liquid with CAMHB culture medium at a ratio of 1:200, adding 96-well plates, 12-well each row, and each rowWells 200uL. The medium appeared clear after 24 hours with both Staphylococcus aureus ATCC29213 and Escherichia coli ATCC25922, to which 50uM LTX-315 polypeptide was added, no bacterial growth was observed, OD 600 Are less than 0.1. It can be seen that LTX-315 polypeptide has potential antibacterial activity against Staphylococcus aureus and Escherichia coli. The addition of LTX-315 polypeptide to 50um, after 24 hours incubation at 37 ℃ was observed and the compound added to the wells where no bacterial growth could be seen with the naked eye was considered to have potential bacteriostatic activity.
IN addition, the compounds added to the wells IN which the growth of bacteria was not visible to the naked eye were considered to have potential bacteriostatic activity, as observed after incubation at 37℃for 24 hours, by using T CU-CPT-9a, HO-1-IN-1, SAHA chloroalkane T1, SKA-121 and the like as comparative examples, respectively.
In this example, both Staphylococcus aureus ATCC29213 and Escherichia coli ATCC25922 added with 50uM LTX-315 polypeptide showed clear culture medium after 24 hours, no growth of bacteria was observed, OD 600 Are less than 0.1. However, bacteria still grow IN the added T CU-CPT-9a, HO-1-IN-1, SAHA chloroalkane T1 and SKA-121. It can be seen that LTX-315 polypeptide has potential antibacterial activity against Staphylococcus aureus and Escherichia coli.
Example 2
In this example, a minimal inhibitory concentration MIC of LTX-315 polypeptide against 62 clinically isolated gram-positive strains (including 20 methicillin-sensitive staphylococcus aureus MSSA, 20 methicillin-resistant staphylococcus aureus MRSA, 22 staphylococcus epidermidis) and 64 gram-negative bacteria (including 19 Acinetobacter baumannii, 20 pseudomonas aeruginosa and 25 escherichia coli) was detected by a micro broth dilution method, and the specific steps are:
taking overnight culture bacteria liquid, adjusting turbidity to 0.5 McGeranium (bacterial amount about 1.0-1.5X10) 8 cfu/mL). The bacterial liquid and the CAMHB culture medium are diluted 1:100 and then added into a 96-well plate, 10 gradient holes (128,64,32,16,8,4,2,1,0.5,0.25 mu g/mL) are arranged on each row of 12 holes, 200uL of the bacterial liquid is added into the 11 th hole to be used as a positive control, and 200uL of the CAMHB culture medium is added into the 12 th hole to be used as a negative control. MIC value of each antibacterial agentDetermination of culture conditions and time following CLSI guidelines, observations were made after incubation at 37 ℃ for 18 hours, and MIC values were calculated as drug concentration wells where bacterial fluid precipitation was not visible to the naked eye.
In the embodiment, the MIC value results of the LTX-315 polypeptide on gram-positive bacteria such as staphylococcus aureus, staphylococcus epidermidis and the like and gram-negative bacteria such as Acinetobacter baumannii, pseudomonas aeruginosa and escherichia coli are shown in table 1, and the LTX-315 polypeptide has relatively broad-spectrum antibacterial activity on various gram-positive bacteria and gram-negative bacteria, and the MIC value is mainly distributed between 4 mug/mL and 64 mug/mL, wherein the inhibitory effect on staphylococcus epidermidis is optimal 50 4. Mu.g/mL.
TABLE 1 MIC value distribution of common gram-positive and gram-negative clinical strains for LTX-315 polypeptide
Note that: MIC: minimum inhibitory concentration; MSSA: methicillin-sensitive staphylococcus aureus; MRSA: methicillin-resistant staphylococcus aureus; the method comprises the steps of carrying out a first treatment on the surface of the S. epidemic: staphylococcus epidermidis; peneumoniae: klebsiella pneumoniae; e.coli: escherichia coli; baumannii: acinetobacter baumannii; aerucinosa: pseudomonas aeruginosa; n is the number of strains tested. MIC (MIC) 50 Inhibiting the drug concentration required by the growth of 50% of the test bacteria; MIC (MIC) 50 : drug concentration required to inhibit 90% of the growth of the test bacteria.
Example 3
LTX-315 polypeptide has an effect on growth of gram-positive and gram-negative bacteria.
To verify whether LTX-315 polypeptides could inhibit bacterial growth, we treated 2 strains of Staphylococcus aureus (CHS 101 and YUSA 145), 2 strains of Acinetobacter baumannii (AB 2220 and AB 2221), and 2 strains of Escherichia coli (ECO 2201 and ECO 2221), respectively, with different subinhibitory concentrations of LTX-315 polypeptides, and detected their absorbance at 600nm (OD 600 ) The specific steps are as follows: taking overnight culture broth, and culturing with Tryptone Soybean Broth (TSB)Diluted 1000 times, added to 96-well plate, added with LTX-315 polypeptides of different concentrations (1/16×,1/8×,1/4×,1/2×and1×MIC) and placed in a full-automatic growth curve analyzer, and OD was measured every 1 hour 600 Absorbance, to detect planktonic bacteria content in culture supernatant, incubation temperature is 37 ℃, and growth curve is drawn.
Growth curve analysis As shown in FIG. 1, it was found that LTX-315 polypeptide inhibited growth of all Staphylococcus aureus, acinetobacter baumannii and Escherichia coli planktonic bacteria at 1/4 XMIC and 1/2 XMIC concentrations, and when the concentrations reached 1 XMIC, growth of Staphylococcus aureus, acinetobacter baumannii and Escherichia coli were completely inhibited, and these results primarily indicated that LTX-315 polypeptide had potential as an antibacterial agent.
Example 4
Time and dose relation experiments of LTX-315 polypeptide on gram-positive bacteria and gram-negative bacteria bactericidal activity.
In this example, the time-dependent and dose-dependent effects of LTX-315 polypeptide on the bactericidal activity of Staphylococcus aureus, acinetobacter baumannii and Escherichia coli were studied and compared with the activity of the clinical antibiotics vancomycin or levofloxacin, the specific steps include:
will log phase (OD 600 MRSA clinical strain YUSA145, a carbapenem-resistant acinetobacter AB2221, an ESBLs-producing escherichia coli clinical strain ECO2201, and 2 ×,8×mic LTX-315 polypeptide, 4×mic vancomycin, or 4×mic levofloxacin, respectively, were diluted 100-fold and incubated with a shaker 200 rpm. Samples were then taken at 0, 2,4, 8, 24 hours, respectively, serially diluted with sterile physiological saline, and plated on TSB plates for incubation at 37℃and colony counts after 24 hours. Colony counts are expressed in CFU/mL.
As shown in figure 2, the obtained sterilization curve analysis shows that the LTX-315 polypeptide has remarkable sterilization effect on staphylococcus aureus, acinetobacter baumannii and escherichia coli at 4 xMIC, and is stronger than vancomycin or levofloxacin; the bacterial count of Acinetobacter baumannii and Escherichia coli is reduced to the detection lower limit within 4 hours at the concentration of 8 xMIC, and the sterilization effect is stronger than that of 4 xMIC vancomycin.
Example 5
The embodiment adopts analysis methods such as fluorescent staining, laser confocal microscope and scanning electron microscope observation to study the action mechanism of the antibacterial activity of the LTX-315 polypeptide, and comprises the following specific steps:
LIVE/DEAD fluorescent staining analysis of the effect of LTX-315 polypeptide on bacterial plasma membrane permeability: LIVE/DEAD BacLight TM The fluorescent dye comprises two different nucleic acid dyes, and can rapidly distinguish living bacteria with complete plasma membranes from dead bacteria with incomplete plasma membranes. Where Propidium Iodide (PI) is used to detect membrane permeability, the fluorescence intensity increases as it passes through the disrupted cell membrane into the bacteria to bind nucleic acids. Logarithmic phase staphylococcus aureus YUSA145 cells were adjusted to OD 600 =0.05, with LIVE/DEAD Baclight TM The fluorochromes were incubated in the dark. The suspensions were then treated with different concentrations of LTX-315 polypeptide, and the treated plankton were observed and photographed by a laser confocal microscope after 1 hour, with 0.1% DMSO as a control, monitoring the Propidium Iodide (PI) staining fluorescence value every 5 minutes for 1 hour.
The monitoring result of the fluorescence intensity is shown in fig. 3 (a), the proportion of red fluorescent bacteria of staphylococcus aureus YUSA145 treated by the LTX-315 polypeptide is found to be obviously increased, and the PI fluorescence value is also shown to be gradually increased in a dose-dependent manner after the LTX-315 polypeptide is treated as shown in fig. 3 (b), which shows that the permeability of a bacterial plasma membrane is changed, and the LTX-315 polypeptide has an injury effect on the cell membrane of staphylococcus aureus.
Membrane potential measurement: membrane potential measurement was performed using a membrane potential sensitive fluorescent probe DiBAC4 (3). The strain YUSA145 in exponential growth phase was collected by centrifugation and washed thoroughly 3 times with HEPES buffer (pH 7.2,5 mM) containing 20mM glucose. Subsequently, bacterial cells were resuspended at OD 600 0.5 and 1. Mu.M DiBAC4 (3) was incubated in the dark at 37℃to allow the dye to enter the cell membrane. Following incubation, the cell suspension was treated to LTX-315 polypeptide at 1/2,1 x or 2 x MIC concentrations, while solvent DMSO-treated cells were added as controls. Imaging of multimode reader (BioTek, USA) using Cystation 5 cells at excitation wavelength 492nm and emission wavelength 5Fluorescence intensity was monitored every 5 minutes at 18nm for 60 minutes.
As shown in FIG. 3 (b), the membrane potential monitoring result shows that the proportion of DiBAC4 (3) of staphylococcus aureus YUSA145 treated by the LTX-315 polypeptide is obviously increased, and the fluorescence value also shows gradient increase, which indicates that the LTX-315 polypeptide changes the state of a bacterial membrane.
Cell morphology was observed by transmission electron microscopy: MRSA isolate YUSA145 was grown in TSB to 37℃in the logarithmic growth phase. Then, the bacteria were collected and treated with LTX-315 polypeptide at 4 XMIC concentration for 4 hours. After treatment, the cells were washed with phosphate buffer and fixed with 2.5% glutaraldehyde and 1% tungstic acid at 4℃for 2 hours. The samples were dehydrated through progressive ethanol and twice acrylate. The samples were fixed and sectioned and then observed under a transmission electron microscope.
The result of the transmission electron microscope is shown in fig. 3 (d), and the result of the transmission electron microscope shows that partial bacterial cells treated by the LTX-315 polypeptide are ruptured and the cytoplasm is leaked, so that the LTX-315 polypeptide has obvious damage to the integrity of bacteria.
Further in order to analyze whether the damage of the LTX-315 polypeptide to the bacterial integrity is related to the cell membrane, a checkerboard trace broth dilution method is adopted to detect the influence of different concentrations of bacterial plasma membrane phospholipid components Phosphatidylglycerol (PG), phosphatidylethanolamine (PE) and Cardiolipin (CL) on the minimum inhibitory concentration MIC of the LTX-315 polypeptide, and the method comprises the following specific steps: taking overnight Staphylococcus aureus YUSA145 and Escherichia coli culture solution, and adjusting turbidity to 0.5 McO (bacterial amount about 1.0-1.5X10) 8 cfu/mL). Diluting bacterial liquid and a CAMHB culture medium by 1:100, adding a 96-well plate, wherein 10 gradient holes (512,256,128,64,32,16,8,4,2,1 mu g/mL) are formed in each row of 12 holes and LTX-315 polypeptide, 200uL of the bacterial liquid is added into the 11 th hole to be used as a positive control, and 200uL of the CAMHB culture medium is added into the 12 th hole to be used as a negative control; the membrane phospholipid fraction was provided with 8 gradient wells (128,64,32,16,8,4,2,1. Mu.g/mL). After incubation at 37℃for 18 hours, the results were observed, and MIC values were calculated from the drug concentration wells in which no sedimentation of the bacterial liquid could be seen with naked eyes.
The results obtained are plotted with the concentrations of different phospholipids as the abscissa and the MIC concentration fold change of the LTX-315 polypeptide as the ordinate, and as shown in FIG. 3 (e), exogenous addition of Phosphatidylglycerol (PG) and Cardiolipin (CL) to the culture medium reduces the bacteriostatic activity of the LTX-315 polypeptide and is dose dependent, and it can be seen that the LTX-315 polypeptide targets phosphatidylglycerol and cardiolipin of bacterial plasma membrane and destroys bacterial cell membrane to exert bacteriostatic activity.
Example 6
The embodiment is a verification experiment of the synergistic antibacterial effect of LTX-315 polypeptide and cephalosporin antibiotics on gram-negative bacteria, and the sensitivity of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli to the cephalosporin antibiotics is seen, and the specific steps are as follows:
first, changes in MIC of the Acinetobacter carbapenem-resistant and the cephalosporin antibiotics of the E.coli strain were analyzed at a 1/4 XMIC LTX-315 polypeptide concentration: taking overnight culture bacteria liquid, adjusting turbidity to 0.5 McGeranium (bacterial amount about 1.0-1.5X10) 8 cfu/mL). The bacterial liquid and the CAMHB culture medium are diluted 1:100 and then added into a 96-well plate, 10 gradient holes (128,64,32,16,8,4,2,1,0.5,0.25 mu g/mL) are arranged on each row of 12 holes, 200uL of the bacterial liquid is added into the 11 th hole to be used as a positive control, and 200uL of the CAMHB culture medium is added into the 12 th hole to be used as a negative control. MIC value determination of each antibacterial agent the culture conditions and time were carried out according to the CLSI guidelines, and after incubation at 37℃for 18 hours, the results were observed and the MIC value was calculated as the concentration of the drug in the well where no sedimentation of the bacterial liquid could be seen with naked eyes.
MIC value results are shown in Table 2, and it is seen that the carbapenem-resistant Acinetobacter baumannii and carbapenem-resistant Escherichia coli strains, including ceftazidime, ceftriaxone and cefepime, all show drug resistance, MIC is greater than 128 mug/mL, and addition of 1/4 XMIC (8 mug/mL) LTX-315 polypeptide can make all carbapenem-resistant Acinetobacter baumannii and carbapenem-resistant Escherichia coli strains insensitive to the cephalosporins again, and MIC is reduced to below 8 mug/mL.
TABLE 2 MIC value distribution of clinical strains of gram-negative bacteria for LTX-315 polypeptide
Note that: e.coli: escherichia coli; baumannii: acinetobacter baumannii; ceftazidime: ceftazidime; ceftriaxone: ceftriaxone; cefapime: cefepime.
The following is a test of the LTX-315 polypeptide and ceftriaxone combination on the growth curve of the strain AB2220 of the strain A.carbapenem-Bowman. To verify whether LTX-315 polypeptide has a synergistic effect with ceftriaxone to inhibit bacterial growth, we treated a clinical strain AB2220 of a. Carbapenem. Baumannii with 1/4×mic LTX-315 polypeptide at different concentrations (16, 8,4,2,1 μg/mL) with ceftriaxone, respectively, and tested its OD values at different time points, the specific steps were: taking overnight culture bacteria liquid, diluting with Tryptone Soybean Broth (TSB) culture medium for 1000 times, adding into 96-well plate, adding different concentrations of LTX-315 polypeptide and ceftriaxone, placing into full-automatic growth curve analyzer, and measuring OD every 1 hr 600 Detecting the content of planktonic bacteria in the culture supernatant, and drawing a growth curve at the incubation temperature of 37 ℃.
Growth curve analysis As shown in FIG. 4 (b), when taken alone, 64. Mu.g/mL of ceftriaxone had no effect on the growth of the Acinetobacter carbapenem-resistant clinical strain AB2220, whereas after combination with LTX-315 polypeptide, 4. Mu.g/mL of ceftriaxone completely inhibited the growth of the Acinetobacter carbapenem-resistant clinical strain AB2220 as shown in FIG. 4 (c).
The following test of the sterilizing curves of LTX-315 polypeptide and ceftriaxone on the carbapenem-resistant Acinetobacter baumannii clinical strains AB2220 and AB2221 plankton. Will log phase (OD 600 2=0.5) of the carbapenem-resistant acinetobacter baumanii clinical strains AB2220 and AB2221 were diluted 100-fold, and 16 μg/mL of LTX-315 polypeptide and 64 μg/mL of ceftriaxone were added, respectively, and incubated on a shaker at 200 rpm. Samples were then taken at 0, 2,4, 8, 24 hours, respectively, serially diluted with sterile physiological saline, and plated on TSB plates for incubation at 37℃and colony counts after 24 hours. Colony counts are expressed in CFU/mL.
As shown in FIG. 5, the analysis of the obtained sterilization curve shows that the LTX-315 polypeptide and ceftriaxone have synergistic sterilization effects on the carbapenem-resistant Acinetobacter baumannii clinical strains AB2220 and AB2221 plankton, and the independent 16 mug/mL LTX-315 polypeptide and 64 mug/mL ceftriaxone have no sterilization activity on the AB2220 and AB2221 plankton, and the combined use shows a stronger sterilization effect.
Example 7
The experimental example is an influence experiment of LTX-315 polypeptide on human vascular endothelial cell HUEVC, monocyte line J774a.1, human kidney epithelial cell line 293T and human kidney epithelial cell line 293T cytotoxicity, and comprises the following specific steps:
100. Mu.L of human vascular endothelial cell HUEVC, monocyte line J774a.1 or human renal epithelial cell line 293T cytotoxic cell suspension were prepared in 96 well plates. The plates were pre-incubated in an incubator for 24 hours (37 ℃,5% co 2). To the plates were added 10. Mu.L of LTX-315 polypeptide at various concentrations, and 8 gradient wells (128,64,32,16,8,4,2,1. Mu.g/mL) were set. The plates were incubated in an incubator for 24 hours and 10. Mu.L of CCK-8 solution was added to each well. The plates were incubated in the incubator for 1-4 hours. The absorbance at 450nm was measured with a microplate reader. Cell viability was then calculated by absorbance.
The CCK-8 kit is a rapid high-sensitivity detection kit widely applied to cell proliferation and cytotoxicity based on WST-8 (chemical name: 2- (2-methoxy-4-nitrophenyl) -3- (4-nitrophenyl) -5- (2, 4-disulfophenyl) -2H-tetrazolium monosodium salt). The working principle is as follows: in the presence of an electron coupling reagent, it can be reduced by intramitochondrial dehydrogenases to yield a highly water-soluble orange-yellow formazan product (formazan). The shade of color is proportional to the proliferation of cells and inversely proportional to cytotoxicity. The OD value was measured at a wavelength of 450nm using an enzyme-labeled instrument, indirectly reflecting the number of living cells.
The result of LTX-315 polypeptide on HUEVC, J774a.1 and 293T cytotoxicity is shown in figure 6, and it can be seen that LTX-315 polypeptide has small cytotoxicity, has no obvious effect on proliferation of several cells at the concentration of less than 64 mu g/mL, is higher than MIC value of most clinical strains detected, and has potential clinical anti-infection application potential.
Example 8
The embodiment is an anti-infection treatment experiment of LTX-315 polypeptide combined with ceftriaxone on the pulmonary infection of a carbapenem acinetobacter strain AB2220, which comprises the following specific steps:
a7-8 week old BALB/C mouse was used to establish a model of the E.carbapenem-resistant Acinetobacter baumannii infected lung. To prepare an inoculum, a clinical strain of Acinetobacter baumannii, resistant to carbapenem, AB2220 was cultured in 5mL of culture broth, incubated at 37℃for 16 hours, then diluted 1:100 and inoculated into 50mL of fresh medium, and cultured with shaking at 37℃to OD 600 To about 0.5. Bacteria were collected by centrifugation for 10 minutes, resuspended in 1/10 volume of 0.9% saline, diluted in partial doubles, and plated. The cotton ball is dipped with isoflurane by forceps, the mice are anesthetized in a cage, and the mice are taken out after losing consciousness. Bacterial droplets were injected into nasal mice via the respiratory tract into pulmonary infections using a pipette. 1 hour after inoculation, the administration was intraperitoneal injection, and a control group (physiological saline), a single administration group (LTX-315 polypeptide or ceftriaxone, at a dose of 50 mg/kg) and a combination administration group (LTX-315 polypeptide and ceftriaxone, both at a dose of 50 mg/kg) were established. The following day of cervical dislocation mice were sacrificed, lungs were homogenized for 5 minutes, and bacterial Colony Forming Units (CFU) counts were determined by serial dilution.
As shown in fig. 7, compared with the normal saline control group, the single administration of LTX-315 polypeptide or ceftriaxone cannot reduce the bacterial load of carbapenem-resistant acinetobacter in the lung, and the combination of LTX-315 polypeptide and ceftriaxone can significantly reduce the bacterial load in the lung, which indicates that the combination of LTX-315 polypeptide and ceftriaxone has anti-infective treatment effect on the lung infection caused by carbapenem-resistant acinetobacter baumannii.
All of the above experiments were performed with GraphPad Prism 8.0 software for data processing and image rendering. P <0.05 was considered statistically different.
Example 9
Use of an LTX-315 polypeptide for the preparation of a bacterial inhibition coating for the surface of a medical device, said LTX-315 polypeptide having CAS number 1345407-05-7, said LTX-315 polypeptide having bacterial growth inhibition and biofilm formation inhibition.
Further, in the coating, the concentration of the LTX-315 polypeptide is not less than 2 mug/mL.
Furthermore, the coating also comprises cephalosporin antibiotics, and the LTX-315 polypeptide can reverse the drug resistance of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli, so that the carbapenem-resistant acinetobacter baumannii and the carbapenem-resistant escherichia coli are sensitive to the cephalosporin antibiotics.
Example 10
Use of an LTX-315 polypeptide having CAS number 1345407-05-7 for the preparation of an antimicrobial agent, said LTX-315 polypeptide having inhibitory effects on bacterial growth and biofilm formation.
Furthermore, the antibacterial agent also comprises cephalosporin antibiotics, and the LTX-315 polypeptide can reverse the drug resistance of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli, so that the carbapenem-resistant escherichia coli is sensitive to the cephalosporin antibiotics.
The foregoing is a further detailed description of the invention in connection with the preferred embodiments, and it is not intended that the invention be limited to the specific embodiments described. It will be apparent to those skilled in the art that several simple deductions or substitutions may be made without departing from the spirit of the invention, and these should be considered to be within the scope of the invention.
Claims (10)
- The application of LTX-315 polypeptide in preparing antibacterial infection medicines is characterized in that: the CAS number of the LTX-315 polypeptide is 1345407-05-7, and the LTX-315 polypeptide has the effects of inhibiting bacterial growth and biofilm formation.
- 2. The use of LTX-315 polypeptide according to claim 1 for the preparation of a medicament for the treatment of bacterial infections, characterized in that: the bacteria comprise gram-positive bacteria and gram-negative bacteria, wherein the gram-positive bacteria are at least one of staphylococcus aureus, enterococcus faecalis, enterococcus faecium, staphylococcus epidermidis or streptococcus pneumoniae, and the gram-negative bacteria are at least one of acinetobacter baumannii, klebsiella pneumoniae, escherichia coli and pseudomonas aeruginosa.
- 3. Use of LTX-315 polypeptide according to claim 2 for the preparation of a medicament for the treatment of bacterial infections, characterized in that: the concentration of the LTX-315 polypeptide in a treatment system is not less than 2 mug/mL.
- 4. Use of LTX-315 polypeptide according to claim 2 for the preparation of a medicament for the treatment of bacterial infections, characterized in that: the medicine is injection, tablet, pill, capsule, suspending agent, granule, spray or emulsion.
- 5. Use of LTX-315 polypeptide according to claim 2 for the preparation of a medicament for the treatment of bacterial infections, characterized in that: the medicine also comprises cephalosporin antibiotics, and the LTX-315 polypeptide can reverse the drug resistance of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli, so that the carbapenem-resistant acinetobacter baumannii and the carbapenem-resistant escherichia coli are sensitive to the cephalosporin antibiotics.
- Use of ltx-315 polypeptide for the preparation of a bacterial inhibition coating, characterized in that: the coating is used for the surface of a medical appliance, the CAS number of the LTX-315 polypeptide is 1345407-05-7, and the LTX-315 polypeptide has the effects of inhibiting bacterial growth and biofilm formation.
- 7. Use of LTX-315 polypeptide according to claim 6 for the preparation of a bacterial inhibition coating, characterized in that: in the coating, the concentration of the LTX-315 polypeptide is not less than 2 mug/mL.
- 8. Use of LTX-315 polypeptide according to claim 6 for the preparation of a bacterial inhibition coating, characterized in that: the coating also comprises cephalosporin antibiotics, and the LTX-315 polypeptide can reverse the drug resistance of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli, so that the carbapenem-resistant acinetobacter baumannii and the carbapenem-resistant escherichia coli are sensitive to the cephalosporin antibiotics.
- The use of ltx-315 polypeptide for the preparation of an antibacterial agent, characterized in that: the CAS number of the LTX-315 polypeptide is 1345407-05-7, and the LTX-315 polypeptide has the effects of inhibiting bacterial growth and biofilm formation.
- 10. The use of LTX-315 polypeptide according to claim 9 for the preparation of an antibacterial agent, characterized in that: the antibacterial agent also comprises cephalosporin antibiotics, and the LTX-315 polypeptide can reverse the drug resistance of the carbapenem-resistant acinetobacter baumannii and carbapenem-resistant escherichia coli, so that the carbapenem-resistant escherichia coli is sensitive to the cephalosporin antibiotics.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310502310.2A CN116617355A (en) | 2023-05-06 | 2023-05-06 | Application of LTX-315 polypeptide in preparation of antibacterial infection resisting drugs |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310502310.2A CN116617355A (en) | 2023-05-06 | 2023-05-06 | Application of LTX-315 polypeptide in preparation of antibacterial infection resisting drugs |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116617355A true CN116617355A (en) | 2023-08-22 |
Family
ID=87620471
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310502310.2A Pending CN116617355A (en) | 2023-05-06 | 2023-05-06 | Application of LTX-315 polypeptide in preparation of antibacterial infection resisting drugs |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116617355A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118453832A (en) * | 2024-07-10 | 2024-08-09 | 核工业总医院 | Application of immunomodulatory peptide in preparation of medicines for preventing and treating bacterial infection |
-
2023
- 2023-05-06 CN CN202310502310.2A patent/CN116617355A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118453832A (en) * | 2024-07-10 | 2024-08-09 | 核工业总医院 | Application of immunomodulatory peptide in preparation of medicines for preventing and treating bacterial infection |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Zharkova et al. | Application of antimicrobial peptides of the innate immune system in combination with conventional antibiotics—a novel way to combat antibiotic resistance? | |
| Martins et al. | Suppl 1: Mechanisms of resistance in bacteria: An evolutionary approach | |
| Zhu et al. | Bactericidal efficiency and modes of action of the novel antimicrobial peptide T9W against Pseudomonas aeruginosa | |
| CN116617355A (en) | Application of LTX-315 polypeptide in preparation of antibacterial infection resisting drugs | |
| Vasudevan et al. | Reciprocal cooperation of type A procyanidin and nitrofurantoin against multi-drug resistant (MDR) UPEC: a pH-dependent study | |
| Siriphap et al. | Antimicrobial activity of the green tea polyphenol (−)-epigallocatechin-3-gallate (EGCG) against clinical isolates of multidrug-resistant Vibrio cholerae | |
| Donnert et al. | Targeting bioenergetics is key to counteracting the drug-tolerant state of biofilm-grown bacteria | |
| Li et al. | Anti-hepatitis C virus drug simeprevir: a promising antimicrobial agent against MRSA | |
| Tong et al. | Benzydamine reverses TMexCD-TOprJ-mediated high-level tigecycline resistance in Gram-negative bacteria | |
| Singaravelu et al. | Lectin-fortified cationic copper sulfide nanoparticles gain dual targeting capabilities to treat carbapenem-resistant Acinetobacter baumannii infection | |
| Walker et al. | Evaluation of the impact of methicillin‐resistant Staphylococcus pseudintermedius biofilm formation on antimicrobial susceptibility | |
| Hwang et al. | Membrane‐Active Metallopolymers: Repurposing and Rehabilitating Antibiotics to Gram‐Negative Superbugs | |
| Guo et al. | Metformin reverse minocycline to inhibit minocycline-resistant Acinetobacter baumannii by destroy the outer membrane and enhance membrane potential in vitro | |
| US8445452B2 (en) | Fulvic acid and antibiotic combination | |
| Rabadia et al. | Study of synergistic action of cefotaxime and Terminalia chebula on Acinetobacter baumannii using checkerboard assay | |
| Rios et al. | Repurposing streptomycin and chloramphenicol against bacterial pathogens by combination with diminazene aceturate | |
| Qiao et al. | Effects of polyethyelene glycol-desferrioxamine: gallium conjugates on Pseudomonas aeruginosa outer membrane permeability and vancomycin potentiation | |
| Zhang et al. | Famotidine Enhances Rifampicin Activity against Acinetobacter baumannii by Affecting OmpA | |
| Elshimy et al. | 9-Methoxyellipticine: antibacterial bioactive compound isolated from Ochrosia elliptica Labill. Roots | |
| Wu et al. | Simeprevir restores the anti-Staphylococcus activity of polymyxins | |
| CN116549464B (en) | Application of long-chain alkyl TPP compound in preparation of antibacterial infection resisting medicine | |
| Bouali et al. | Methicillin-resistant Staphylococcus aurous: epidemiology, transmission and new alternative therapies: a narrative review | |
| CN116509848B (en) | Application of A Ji Ruige in preparation of medicine for resisting gram-positive bacterial infection | |
| Hussein | Antibacterial Activity of Lantana camara Flower Extracts Against Growth of Pathogenic Bacteria Isolated from Wounds and Burns Infections | |
| Slade-Vitković et al. | In Vitro Antibiofilm Activity of Fosfomycin Alone and in Combination with Other Antibiotics against Multidrug-Resistant and Extensively Drug-Resistant Pseudomonas aeruginosa |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |