CN105154416A - Cellobiose hydrolase mutant and application thereof - Google Patents

Cellobiose hydrolase mutant and application thereof Download PDF

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CN105154416A
CN105154416A CN201510687816.0A CN201510687816A CN105154416A CN 105154416 A CN105154416 A CN 105154416A CN 201510687816 A CN201510687816 A CN 201510687816A CN 105154416 A CN105154416 A CN 105154416A
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mutant
cellobiohydrolase
enzyme
cellobiose hydrolase
trichodermareesei
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李�瑞
张青
李宾
王华明
黄亦钧
许丽红
许韦
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Qingdao Vland Biotech Group Co Ltd
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    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
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    • C12N9/14—Hydrolases (3)
    • C12N9/24—Hydrolases (3) acting on glycosyl compounds (3.2)
    • C12N9/2402—Hydrolases (3) acting on glycosyl compounds (3.2) hydrolysing O- and S- glycosyl compounds (3.2.1)
    • C12N9/2405—Glucanases
    • C12N9/2434—Glucanases acting on beta-1,4-glucosidic bonds
    • C12N9/2437—Cellulases (3.2.1.4; 3.2.1.74; 3.2.1.91; 3.2.1.150)
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    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
    • C12P7/00—Preparation of oxygen-containing organic compounds
    • C12P7/02—Preparation of oxygen-containing organic compounds containing a hydroxy group
    • C12P7/04—Preparation of oxygen-containing organic compounds containing a hydroxy group acyclic
    • C12P7/06—Ethanol, i.e. non-beverage
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12Y—ENZYMES
    • C12Y302/00—Hydrolases acting on glycosyl compounds, i.e. glycosylases (3.2)
    • C12Y302/01—Glycosidases, i.e. enzymes hydrolysing O- and S-glycosyl compounds (3.2.1)
    • C12Y302/01091—Cellulose 1,4-beta-cellobiosidase (3.2.1.91)
    • 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
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/10—Biofuels, e.g. bio-diesel

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Abstract

The invention relates to the technical field of enzyme gene engineering modification, particularly a cellobiose hydrolase mutant. The amino acid sequence of the cellobiose hydrolase mutant is SEQ ID NO:3, and one nucleic acid sequence of the coding gene is SEQ ID NO:4. The cellobiose hydrolase mutant provided by the invention has higher acid resistance than the wild type, the optimal pH is 5.0, and the cellobiose hydrolase mutant can keep the enzyme activity level of 65% or above within the pH range of 3.5-7.0; and the optimal pH of the wild type is 5.5. The cellobiose hydrolase mutant can be widely used for lignocellulose degradation, and can obviously enhance the saccharification rate of the lignocellulose. The saccharification rate of lignocellulose of the cellobiose hydrolase mutant MAF6A in the experimental group 2 is enhanced by 6.5% as compared with the control group, and enhanced by 3.5% as compared with the experimental group 1 with the wild type cellobiose hydrolase AF6A, thereby obtaining unexpected technical effects.

Description

A kind of cellobiohydrolase mutant and application thereof
Technical field
The invention belongs to the genetic engineering modified technical field of enzyme, be specifically related to a kind of cellobiohydrolase mutant and application thereof.
Background technology
Cellulase (Cellulases) is the enzyme that hydrocellulose (β-Isosorbide-5-Nitrae dextran or β-D-glycosidic link) causes being formed glucose, cellobiose, cell-oligosaccharide (cellooligosaccharides) and similar substance.Cellulase has traditionally been divided into three main Types: endoglucanase (endoglucanases, EC3.2.1.4), exoglucanase (exoglucanases) or cellobiohydrolase (cellobiohydrolase, and beta-glucosidase (β-D-glucosideglucohydrolase, EC3.2.1.21) EC3.2.1.91).Endoglucanase mainly acts on the amorphous parts of cellulosic fibre, and exoglucanase cellobiohydrolase is the enzyme component that uniquely can act on crystal fibre element.Therefore, the existence of cellobiohydrolase in cellulase system is required for effective dissolving of crystal fibre element.
Cellobiohydrolase is made up of 3 parts: the catalyst structure domain with catalytic activity, the cellulose binding domain acting as anchoring fibers element and the one section of small peptide connecting these two structural domains.In hydrocellulose process, cellobiohydrolase mainly acts on Mierocrystalline cellulose linear molecule non-reducing end, and hydrolysis β-Isosorbide-5-Nitrae-glycosidic link, cuts next cellobiose molecule at every turn, makes crystalline cellulose become diffluent amorphous cellulose element.
Current economic is too dependent on the fossil oil such as oil, coal, and its non-renewable resource that causes is petered out, and the carbonic acid gas that burning produces has caused going from bad to worse of climatope.Find the focus that reproducible clean energy becomes various countries scientific research personnel concern.Wherein biomass energy is because having the advantages such as wide material sources, cheap, reproducibility is strong, becomes the energy substance of most potentiality.Bio-ethanol is one of important energy source coming from renewable material.Lignocellulose is renewable resources the abundantest on the earth, the plant about 10,000 hundred million tons that the whole world is produced by photosynthesis every year, and for avoiding striving grain with people, lignocellulose will become the raw material of bio-ethanol production most potentiality.
Lignocellulose refining bio-ethanol process generally includes the unit operations such as pre-treatment, hydrolysis, fermentation, distillation, and wherein cellulose hydrolysis is fermentable sugars is vital link in cellulosic ethanol refining process.At present, the degraded of lignocellulose mainly contains chemical method and enzymatic hydrolysis.Compared with being hydrolyzed with chemical method, enzymatic hydrolysis mild condition, equipment is simple, and energy consumption is low, has the features such as by product is few, environmental friendliness simultaneously, in widespread attention and make substantial progress.
Because the Mierocrystalline cellulose in lignocellulose mainly exists with crystalline state, therefore the effect of cellobiohydrolase in lignocellulose hydrolysis is quite important.But current existing cellobiohydrolase vigor is low, consumption enzyme amount is large, and fermentation costs is high, and its enzymolysis efficiency in acid condition and transformation efficiency generally on the low side, seriously limit the application of lignocellulose in bio-ethanol is produced.
Summary of the invention
The object of this invention is to provide a kind of cellobiohydrolase variant and application thereof.The present invention, by carrying out protein engineering transformation to cellobiohydrolase, obtains mutant protein.Described mutant enzyme activity is in acid condition significantly improved, and thermotolerance is stronger, greatly can improve the degradation efficiency of lignocellulose, and then promotes its application in bio-ethanol is produced.
One aspect of the present invention provides a kind of cellobiohydrolase mutant, cellobiohydrolase the 158th amino acids of to be aminoacid sequence be SEQIDNO:1 becomes Asn from Asp, 298th amino acids becomes Ser from Asp, and the 434th amino acids becomes Val from Glu.
The aminoacid sequence of above-mentioned cellobiohydrolase mutant is SEQIDNO:3, and the nucleotide sequence of its encoding gene is SEQIDNO:4.
The present invention provides a kind of recombinant plasmid on the other hand, and it carries the gene that encoding sequence is the cellobiohydrolase mutant of SEQIDNO:4.
Present invention also offers a kind of recombinant bacterial strain, obtaining by above-mentioned recombinant plasmid transformed being entered in Trichodermareesei (Trichodermareesei).
Present invention also offers the application of above-mentioned cellobiohydrolase mutant in bio-ethanol is produced.
Cellobiohydrolase mutant provided by the invention is stronger than the acid resistance of wild-type, and its optimal pH is 5.0, and within the scope of pH3.5-7.0, the enzyme running water of more than 65% all can be kept to put down, and the optimal pH of wild-type is 5.5.Described cellobiohydrolase mutant can be widely used in the degraded of lignocellulose, can significantly improve the conversion coefficient of lignocellulose.Wherein, the conversion coefficient adding lignocellulose in the experimental group 2 of cellobiohydrolase mutant MAF6A of the present invention improves 6.5% than control group, improve 3.5% than the experimental group 1 of adding wild-type cellobiohydrolase AF6A, achieve unexpected technique effect.
Accompanying drawing explanation
Fig. 1: be restructuring strain fermentation supernatant liquor SDS-PAGE electrophoresis detection analysis chart, wherein, swimming lane 1 is Trichodermareesei engineering bacteria AF6A fermented supernatant fluid, swimming lane 2 is Trichodermareesei engineering bacteria MAF6A fermented supernatant fluid, swimming lane 3 is control group Host Strains Trichodermareesei SCHD4 fermented supernatant fluid, and in swimming lane 1 and 2, the protein band at arrow indication 50kDa place is respectively recombinant expressed cellobiohydrolase AF6A and mutant MAF6A;
Fig. 2: be cellobiohydrolase mutant enzyme relative to wild-type pH-graphic representation alive.
Embodiment
The present invention has used routine techniques and the method for genetic engineering and biology field use, such as MOLECULARCLONING:ALABORATORYMANUAL, 3ndEd. (Sambrook, 2001) method and described in CURRENTPROTOCOLSINMOLECULARBIOLOGY (Ausubel, 2003).These general reference provide definition well known by persons skilled in the art and method.But the present invention is not limited to described any concrete grammar, experimental program and reagent.
Describe the present invention below in conjunction with concrete embodiment.
Embodiment 1: the screening of cellobiohydrolase mutant gene
In order to improve wild-type cellobiohydrolase AF6A, (aminoacid sequence is SEQIDNO:1, coding nucleotide sequence is SEQIDNO:2, synthesized by Shanghai Sheng Gong biotechnology limited-liability company) enzyme activity in acid condition, carried out the screening of mass mutation by directed evolution technologies to this enzyme, PCR primer AF6A-F1, AF6A-R1 are as follows in design:
AF6A-F1:GGC gAATTCaTGAAGCACCTTGCATCTTCC (underscore is restriction enzyme EcoRI recognition site);
AF6A-R1:ATA gCGGCCGCtTAAAAGGACGGGTTAGCGTTGG (underscore is restriction enzyme NotI recognition site).
With wild-type cellobiohydrolase AF6A genes of SEQ IDNO:2 for template, above-mentioned primer GeneMorphII random mutation PCR kit (Stratagene) is utilized to carry out pcr amplification, glue reclaims PCR primer, EcoRI, NotI carry out enzyme cut process after pET21a carrier after cutting through same enzyme connect, be converted in e. coli bl21 (DE3), coat LB+Amp flat board, be inverted for 37 DEG C and cultivate, after son to be transformed occurs, choose to 96 orifice plates one by one with toothpick, the LB+Amp substratum that 150 μ L contain 0.1mMIPTG is added in each hole, 37 DEG C, 220rpm cultivates about 6h, centrifugally abandon supernatant, thalline damping fluid is resuspended, multigelation broken wall, obtain the Bacillus coli cells lysate containing cellobiohydrolase.
Respectively get 50 μ L lysates to two piece 96 new orifice plates, under the condition of pH6.0 and pH4.0, measure its cellobiohydrolase enzyme respectively live.Found that, some muton is lived at the enzyme of acidic conditions and is not changed, the enzyme of some muton is lived and is even reduced, DNA sequencing is carried out to the muton still keeping high enzyme to live under pH4.0 condition, finally, applicant obtains mutational site combination D158N, D298S and the E434V that can significantly improve the acid tolerance of cellobiohydrolase.
By the cellobiohydrolase mutant called after MAF6A containing D158N, D298S and E434V mutational site, its aminoacid sequence is SEQIDNO:3, and coding nucleotide sequence is SEQIDNO:4.SEQIDNO:4 is synthesized by Shanghai Sheng Gong biotechnology limited-liability company, and adds KpnI and XbaI two restriction enzyme sites respectively at composition sequence 5 ' and 3 ' two ends.
Gene fragment restriction enzyme KpnI and XbaI (Fermentas) after synthesis is carried out enzyme cut; Meanwhile, carry out enzyme with restriction enzyme KpnI and XbaI to carrier pTG to cut; Gel reclaims goal gene fragment and carrier; And with T4DNA ligase enzyme, above-mentioned two fragments are connected, transform Trans5 α intestinal bacteria, screen with penbritin.For guaranteeing accurately, to check order (Invitrogen) to some clones.
Use amount in plasmid to prepare test kit (Axygen) plasmid purification from the correct escherichia coli cloning of sequencing result, will the recombinant expression plasmid called after pTG-MAF6A of cellobiohydrolase mutant gene sequence be carried.
Embodiment 2: the structure of cellobiohydrolase mutant recombinant bacterial strain and checking
(1) protoplastis preparation
Get Trichodermareesei (Trichodermareesei) SCHD4 bacterial strain spore suspension, be inoculated on PDA flat board, cultivate 6 days for 30 DEG C; Until its produce spore abundant after, the bacterium colony cutting about 1cm × 1cm is placed in the liquid nutrient medium containing 120mLYEG+U (0.5% yeast powder, 1% glucose, 0.1% uridine), 30 DEG C, 220rpm shaking culture 14 ~ 16h;
With sterile gauze collecting by filtration mycelium, and with sterile water wash once; Mycelium is placed in the triangular flask containing 20mL10mg/mL lyase liquid (SigmaL1412), 30 DEG C, 90rpm effect 1-2h; Protoplast transformation progress is detected with microscopic examination;
By 20mL1.2M sorbyl alcohol (1.2M sorbyl alcohol, 50mMTris-Cl, the 50mMCaCl of precooling 2) add in above-mentioned triangular flask, shake up gently, collect filtrate with aseptic Miracloth filter-cloth filtering, 3000rpm, 4 DEG C of centrifugal 10min; Abandon supernatant, add the 5mL1.2M Sorbitol Solution USP suspension thalline of precooling, 3000rpm, 4 DEG C of centrifugal 10min; Abandon supernatant, (200 μ L/ manage, and protoplast concentration is 10 to add the 1.2M sorbyl alcohol suspension packing of appropriate precooling 8individual/mL).
(2) expression vector transforms and host strains
Below operation is all carried out on ice, gets 10 μ g recombinant plasmid pTG-MAF6A and joins in the 7mL sterile centrifugation tube containing 200 μ L protoplast solution, then add 50 μ L25%PEG (25%PEG, 50mMTris-Cl, 50mMCaCl 2), flick at the bottom of pipe and mix, place 20min on ice; Add 2mL25%PEG, after mixing, room temperature places 5min; Add 4mL1.2M sorbyl alcohol, pour into after mixing gently and melt and remain on (0.1%MgSO in the upper strata substratum of 55 DEG C 4, 1%KH 2pO 4, 0.6% (NH 4) 2sO 4, 1% glucose, 18.3% sorbyl alcohol, 0.35% agarose); (2% glucose, 0.5% (NH on the lower floor's culture medium flat plate prepared is layered on gently after mixing 4) 2sO 4, 1.5%KH 2pO 4, 0.06%MgSO 4, 0.06%CaCl 2, 1.5% agar), cultivate 5 ~ 7d for 30 DEG C and grow to there being transformant.
Picking transformant, to lower floor's culture medium flat plate, cultivates 2d for 30 DEG C; Get appropriate mycelium and be placed in 2mL centrifuge tube, add the aseptic quartz sand of 100mg and 400 μ L extraction buffers (100mMTris-HCl, 100mMEDTA, 250mMNaCl, 1%SDS); Instrument thermal agitation 2min is beaten with pearl; After 65 DEG C of water-bath 20min, add 200 μ L10MNH 4aC, ice bath 10min; The centrifugal 10min of 13000rpm; Get supernatant, add the dehydrated alcohol of 2 times of volumes, place 30min for-20 DEG C; The centrifugal 10min of 13000rpm, abandons supernatant; By 70% washing with alcohol 2 times; Dry, be dissolved in water, in-20 DEG C of preservations.
With said extracted transformant genomic dna for template, utilize primer AF6A-F and AF6A-R to carry out pcr amplification goal gene and verify.
AF6A-F：ATGAAGCACCTTGCATCTTCC；
AF6A-R：TTAAAAGGACGGGTTAGCGTTGG；
Pcr amplification condition is 94 DEG C of 4min; 94 DEG C of 40s; 58 DEG C of 40s, 72 DEG C of 1min, 30 circulations; 72 DEG C of 7min, 16 DEG C; Utilize gel to reclaim test kit reclaim pcr amplification product and carry out sequencing analysis, build the Trichodermareesei engineering bacteria obtaining recombinant expressed cellobiohydrolase mutant, by its called after Trichodermareesei MAF6A (TrichodermareeseiMAF6A).
Above-mentioned same method is adopted to build the Trichodermareesei engineering bacteria obtaining recombinant expressed wild-type cellulose enzyme, called after Trichodermareesei AF6A (TrichodermareeseiAF6A).
Embodiment 3 is fermented and is verified and enzyme activity determination
Above-mentioned Trichodermareesei engineering bacteria MAF6A (TrichodermareeseiMAF6A) is inoculated in PDA flat board respectively with Trichodermareesei engineering bacteria AF6A (TrichodermareeseiAF6A), cultivate 1d for 30 DEG C, after spore is abundant, the inoculated by hypha block of getting two pieces of diameter 1cm is respectively in containing 50mL fermention medium (1.5% glucose, 1.7% lactose, 2.5% corn steep liquor, 0.44% (NH 4) 2sO 4, 0.09%MgSO 4, 2%KH 2pO 4, 0.04%CaCl 2, 0.018% tween-80,0.018% trace element) 250mL triangular flask in, 30 DEG C cultivate 48 hours, then 25 DEG C cultivate 48 hours, get fermented supernatant fluid and carry out the analysis of SDS-PAGE electrophoresis detection.Result as shown in Figure 1, in swimming lane 1 and 2, the protein band at arrow indication 50kDa place is respectively cellobiohydrolase AF6A and mutant MAF6A, thus illustrate that the Trichodermareesei engineering bacteria AF6A that the present invention builds can effective expression wild-type cellobiohydrolase AF6A, Trichodermareesei engineering bacteria MAF6A energy effective expression cellobiohydrolase mutant MAF6A.
(1) enzyme activity determination method
50 DEG C, under pH value is the condition of 4.8, per minute enzyme amount of degrading required for release 1 μm of ol p-NP from the solution that concentration is 0.05% p-nitrophenyl-β-D-cellobioside is 1 Ge Meihuo unit.
Get test tube and respectively add the enzyme liquid 0.5ml diluted; Place in 50 ± 0.1 DEG C of water-baths, preheating 2min simultaneously; Accurately in sample tube, add 0.5mL substrate solution, accurately instant 15min, is rapidly in each pipe and adds sodium carbonate solution 0.2ml, add substrate solution 0.5ml, shake up in blank tube.With blank tube zeroing, measure under spectrophotometer wavelength 410nm.
Enzyme X=A × 1 ÷ 0.5 × n ÷ 15 alive
Wherein: X---enzyme activity unit, IU/g (mL);
A---absorbancy typical curve worthwhile content of p-nitrophenol, μm ol;
1/0.5---the enzyme liquid added amasss;
15---the reaction times of liquid to be measured and substrate;
N---extension rate;
(2) enzyme activity determination result
Adopt aforesaid method to measure cellobiohydrolase enzyme in Host Strains Trichodermareesei SCHD4, Trichodermareesei AF6A and Trichodermareesei MAF6A fermented supernatant fluid respectively to live.Result shows: Host Strains fermented supernatant fluid does not measure enzyme and lives, and Trichodermareesei AF6A and Trichodermareesei MAF6A fermented supernatant fluid enzyme are lived and be respectively 180U/mL and 250U/mL.Thus further illustrate, the recombinant bacterium Trichodermareesei AF6A that the present invention builds and Trichodermareesei MAF6A can distinguish high expression cellobiohydrolase AF6A and mutant MAF6A.
Embodiment 4 characterization analysis
4.1 the suitableeest action pH analyses
Respectively with pH value be 3.0,3.5,4.0,4.5,5.0,5.5,6.0,6.5,7.0,7.5, Trichodermareesei AF6A and Trichodermareesei MAF6A fermented supernatant fluid described in the damping fluid of 8.0 dilution embodiment 3, under 50 DEG C of conditions, measure its cellobiohydrolase enzyme live, live as 100% with the highest enzyme, calculate relative enzyme to live, do the relative enzyme of pH-curve alive.Result as shown in Figure 2, the suitableeest action pH of wild-type cellobiohydrolase AF6A is 5.5, and the suitableeest action pH of cellobiohydrolase mutant MAF6A is 5.0, and within the scope of pH3.5-7.0, the enzyme running water of more than 65% all can be kept to put down, compared with wild-type, the acid resistance of mutant is significantly improved.
4.2 optimum temperature analyses
Respectively at 30 DEG C, 35 DEG C, 40 DEG C, 45 DEG C, 50 DEG C, 55 DEG C, 60 DEG C, 65 DEG C, 70 DEG C, 75 DEG C, under pH5.0 condition, the cellobiohydrolase enzyme measuring Trichodermareesei AF6A and Trichodermareesei MAF6A fermented supernatant fluid described in embodiment 3 is lived, live as 100% with the highest enzyme, calculate relative enzyme to live, do temperature-enzyme curve alive relatively.Result shows: compared with wild-type, the optimum temperature of cellobiohydrolase mutant MAF6A provided by the invention does not change, and optimum temperuture is 60 DEG C.
The application of embodiment 5 cellobiohydrolase in ligocellulose degradation
Prepare the triangular flask of 3 250mL, respectively add 2g over dry corn cob meal (main component is lignocellulose); Be that 1:10 (m/v) adds citric acid-sodium citrate damping fluid 150mL respectively according to solid-to-liquid ratio, pH is about 5.0; Add 4.0mg acidic cellulase L30 (purchased from Weifang KDN Biotechnology Co., Ltd., enzyme 500U/mg alive) respectively; Then in 3 triangular flasks, add 0.6mg acidic cellulase L30,0.6mg cellobiohydrolase AF6A (enzyme 500U/mg alive) and 0.6mg mutant MAF6A (enzyme 500U/mg alive) respectively; Enzymolysis is shaken under 50 DEG C of conditions; After 48h, sample respectively, with its glucose content of bio-sensing analysis-e/or determining, calculate the conversion coefficient of corn cob meal, concrete outcome sees the following form.
The total glucose content of content (mg/g lignocellulosic material) the ÷ substrate (mg/g lignocellulosic material) × 100% of the glucose obtained after conversion coefficient (%)=enzymolysis
Data as can be seen from table, compared with control group, experimental group 1 and 2, by adding cellobiohydrolase, with acidic cellulase acting in conjunction, significantly can promote the degraded of lignocellulose, improves the conversion coefficient of lignocellulose.Wherein, the conversion coefficient adding lignocellulose in the experimental group 2 of cellobiohydrolase mutant MAF6A of the present invention improves 6.5% than control group, improve 3.5% than the experimental group 1 of adding wild-type cellobiohydrolase AF6A, achieve unexpected technique effect.

Claims (8)

1. a cellobiohydrolase mutant, it is characterized in that, cellobiohydrolase the 158th amino acids of described mutant to be aminoacid sequence be SEQIDNO:1 becomes Asn from Asp, and the 298th amino acids becomes Ser from Asp, and the 434th amino acids becomes Val from Glu.
2. mutant as claimed in claim 1, it is characterized in that, the aminoacid sequence of described mutant is SEQIDNO:3.
3. a gene, is characterized in that, the described mutant described in genes encoding claim 1 or 2.
4. gene as claimed in claim 3, it is characterized in that, the nucleotide sequence of described gene is SEQIDNO:4.
5. a recombinant plasmid, is characterized in that, described recombinant plasmid carries the gene described in claim 3 or 4.
6. a recombinant bacterial strain, is characterized in that, recombinant plasmid transformed according to claim 5 enters in Host Strains to prepare by described recombinant bacterial strain.
7. recombinant bacterial strain as claimed in claim 6, it is characterized in that, described Host Strains is Trichodermareesei (Trichodermareesei).
8. mutant according to claim 1 is producing the application in bio-ethanol.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113736807A (en) * 2021-08-26 2021-12-03 中山大学 Cellobiohydrolase, and coding gene and application thereof
CN116334111A (en) * 2023-03-03 2023-06-27 上海市农业科学院 Straw mushroom cellobiose hydrolase and application thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101175860A (en) * 2005-03-15 2008-05-07 维莱尼姆公司 Cellulases, nucleic acids encoding them and methods for making and using them
CN102918151A (en) * 2010-03-31 2013-02-06 诺维信股份有限公司 Cellobiohydrolase variants and polynucleotides encoding same
CN105164254A (en) * 2013-03-08 2015-12-16 诺维信公司 Cellobiohydrolase variants and polynucleotides encoding same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101175860A (en) * 2005-03-15 2008-05-07 维莱尼姆公司 Cellulases, nucleic acids encoding them and methods for making and using them
CN102918151A (en) * 2010-03-31 2013-02-06 诺维信股份有限公司 Cellobiohydrolase variants and polynucleotides encoding same
CN105164254A (en) * 2013-03-08 2015-12-16 诺维信公司 Cellobiohydrolase variants and polynucleotides encoding same

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
登录号：XP_748511.1: "cellobiohydrolase［Aspergillus fumigatus Af293］", 《GENBANK》 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113736807A (en) * 2021-08-26 2021-12-03 中山大学 Cellobiohydrolase, and coding gene and application thereof
CN113736807B (en) * 2021-08-26 2023-05-02 中山大学 Cellobiohydrolase, and coding gene and application thereof
CN116334111A (en) * 2023-03-03 2023-06-27 上海市农业科学院 Straw mushroom cellobiose hydrolase and application thereof
CN116334111B (en) * 2023-03-03 2024-02-09 上海市农业科学院 Straw mushroom cellobiose hydrolase and application thereof

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