CN1737118A - Glycosyl transferred beta-galactosidase bacteria screening method - Google Patents

Glycosyl transferred beta-galactosidase bacteria screening method Download PDF

Info

Publication number
CN1737118A
CN1737118A CN 200510044096 CN200510044096A CN1737118A CN 1737118 A CN1737118 A CN 1737118A CN 200510044096 CN200510044096 CN 200510044096 CN 200510044096 A CN200510044096 A CN 200510044096A CN 1737118 A CN1737118 A CN 1737118A
Authority
CN
China
Prior art keywords
glycosyl
beta
galactosidase
bacteria
screening
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.)
Granted
Application number
CN 200510044096
Other languages
Chinese (zh)
Other versions
CN1313599C (en
Inventor
肖敏
卢丽丽
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shandong University
Original Assignee
Shandong University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Shandong University filed Critical Shandong University
Priority to CNB2005100440962A priority Critical patent/CN1313599C/en
Publication of CN1737118A publication Critical patent/CN1737118A/en
Application granted granted Critical
Publication of CN1313599C publication Critical patent/CN1313599C/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
  • Enzymes And Modification Thereof (AREA)

Abstract

The invention disclosed a screen selecting method for the glycosyl-transferase beta-galactosidase producing bacterium, comprising the following steps: using the lactin as the only scource of carbon, after enriching the microbios, separating it with flat, then screening the beta-galactosidase hydrolyzation activity and galactosyl activity and getting the glycosyl-transferase beta-galactosidase producing bacterium. With utilizing the method of the invention, it is easy and effective to obtain the glycosyl-transferase beta-galactosidase producing bacterium from the nature, and also obtain the high active glycosyl-transferase beta-galactosidase producing bacterium. The method provides new source of bacterial for exploiting the microbiological industry, especially for producting oligo-galactose.

Description

A kind of screening method of glycosyl transferred beta-galactosidase bacteria
Technical field
The present invention relates to a kind of microbe to screen method, relate in particular to a kind of screening method of glycosyl transferred beta-galactosidase bacteria.
Technical background
Oligomeric galactose is one of natural constituents in the breast milk, and its most basic most important physiological function comes from its proliferation function to bifidus bacillus.Because oligomeric galactose has good thermostability and acid resistance, its health-care effect has caused people's very big concern.At present, the production of oligomeric galactose is mainly synthetic by microbial enzyme method, is that substrate commentaries on classics glycosyl is synthetic with the lactose by beta-galactosidase enzymes or Sumylact L promptly.Because the catalytic building-up reactions of Glycosylase is reversible reaction, promptly changes the glycosyl product and can be used as substrate by enzymic hydrolysis, so combined coefficient is not very high.Therefore, seek to produce the focus that the microorganism that changes the active beta-galactosidase enzymes of glycosyl more by force becomes present research, still, in the pertinent literature of retrieval, also do not have the report of the screening method of glycosyl transferred beta-galactosidase bacteria at present in the world.
Summary of the invention
At the deficiencies in the prior art, the purpose of this invention is to provide a kind of glycosyl transferred beta-galactosidase bacteria screening method.
The main points of screening method of the present invention are, the sample microorganism obtains by twice screening active ingredients after the lactose enrichment is selected to cultivate, promptly elder generation carries out the flat board selection after sole carbon source is cultivated the sample microbial enrichment to separate, and then screening beta-galactosidase enzymes hydrolytic activity obtains with changeing the galactosyl activity.
The screening method of glycosyl transferred beta-galactosidase bacteria of the present invention, specifically form by following step:
(1) gets enrichment culture in the nutrient solution that the adding of bacterium sample is sole carbon source with the lactose, described nutrient solution is diluted to 10 with sterilized water -1, 10 -3, 10 -5, 10 -7Gradient is respectively got 200 μ L and is evenly coated on the lactose screening flat board, and bacteria screening is dull and stereotyped selects 35~40 ℃ to cultivate 20~28 hours, and fungi screening is dull and stereotyped selects 26~30 ℃ to cultivate 48~72 hours;
Above-mentioned bacteria screening is selected substratum or slant medium with the bacterium enrichment, and its prescription is: lactose 10 ± 2g/L, and peptone 5 ± 2g/L, yeast powder 10 ± 2g/L, sodium-chlor 3 ± 2g/L, pH 7.0~7.5, and solid medium adds agar 20 ± 2g/L;
Above-mentioned fungi screening is selected substratum or slant medium with the fungi enrichment, and its prescription is: and murphy juice (potato 200 ± 2g/L), lactose 10 ± 2g/L, solid medium add agar 20 ± 2g/L, natural pH;
(2) after the cultivation, the different bacterium colony of picking form carries out separation and purification by plate streaking respectively, repeats 3 times;
(3) isolated strains is carried out microscopy, determine purity: bacterium compares with streptococcus aureus (Staphylococcusaureus) and intestinal bacteria (Escherichia coli), carry out gramstaining, microscopy can be distinguished gram-positive microorganism and Gram-negative bacteria; Fungi is made the water logging sheet, and microscopy can be observed mycelia feature and spore producing method, and preliminary evaluation is to belonging to;
(4) the purifying bacterial strain that above-mentioned microscopy is obtained is inoculated in respectively and produces in the enzymic fermentation nutrient solution, and bacterium was cultivated 16~20 hours in 35~40 ℃ of shaking tables; Fungi was cultivated 40~50 hours in 26~30 ℃ of shaking tables, and shaking speed is 180 rev/mins;
Described product enzymic fermentation culture medium prescription is: lactose 10g/L, peptone 5g/L, yeast powder 10g/L, CaCl 20.11g/L, MnSO 40.001g/L, MgSO 47H 2O 0.3g/L, KH 2PO 40.05g/L, FeSO 47H 2O 0.03g/L, bacterium pH are 7.0~7.5, and fungi pH is 6.0~6.5;
(5) treat that above-mentioned cultivation reaches required bacterium amount after, with 12,000 rev/mins centrifugal 2~5 minutes, collect the bacterium or the yeast that produce in the enzymic fermentation nutrient solution; Obtain mycetocyte for mould with the filter paper suction filtration;
(6) with above-mentioned mycetocyte and beta-galactosidase enzymes hydrolysis substrate---o-NP-β-D-galactoside (o-nitrophenyl-β-D-galactopyranoside, ONPG) in w/v=mg/ μ L, press mycetocyte: the mixed of ONPG solution=1: 9,40 ℃ of reactions 10~15 minutes;
(7) add Na 2CO 3The solution termination reaction, with 12,000 rev/mins centrifugal 2~5 minutes, collect supernatant liquor;
(8) yellow if supernatant liquor is, illustrate that former colourless ONPG has been hydrolyzed into the xanchromatic o-NP by beta-galactosidase enzymes, prove that promptly this mycetocyte contains beta-galactosidase enzymes, be and produce the beta-galactosidase enzymes bacterial strain;
(9) with the mycetocyte of above-mentioned product beta-galactosidase enzymes bacterial strain, in w/v=mg/ μ L, in mycetocyte: the ratio of damping fluid=1: 1, mycetocyte is suspended from the damping fluid, after-20 ℃ of following temperature are freezing fully, put room temperature and thaw, repeat freeze thawing again 2~3 times, so the mycetocyte suspension is the beta-galactosidase enzymes crude enzyme liquid;
(10) with above-mentioned crude enzyme liquid in volume ratio, press crude enzyme liquid: the mixed of lactose solution=1: 3, change glycosyl reaction 4~10 hours in 40~60 ℃, wherein: lactose solution concentration is 30% (w/v), solvent is above-mentioned damping fluid, after question response finishes, and 12,000 rev/min centrifugal 2~5 minutes, supernatant liquor promptly contains changes glycosyl reaction product oligomeric galactose;
(11) above-mentioned reaction product is carried out thin-layer chromatography (Thin-Layer Chromatography, TLC) analyze, judge that enzyme changes the glycosyl activity, wherein, developing agent is a propyl carbinol: ethanol: water=5: 3: 2, developer are 3 of 20% sulphuric acid soln+0.5%, the 5-orcin, in 120 ℃ the baking 10 minutes, the colour developing of sugared spot according to its kind from pale brown look to intense violet color; If generated new oligosaccharides spot near the lactose spot, then the beta-galactosidase enzymes of Chan Shenging has the glycosyl of commentaries on classics activity; Do not change the glycosyl activity otherwise then do not exist;
(12) big more, many more with the oligosaccharides spot, illustrate promptly that the commentaries on classics glycosyl activity of enzyme is strong more and be foundation that the active higher bacterial strain of glycosyl transferred beta-galactosidase is produced in screening.
Wherein, dull and stereotyped preferential 37 ℃ of cultivations 24~26 hours of selecting of above-mentioned bacteria screening, the fungi screening flat board is preferential selects 28 ℃ to cultivate 48~60 hours.
Wherein, above-mentioned bacteria screening selects substratum or slant medium formula optimization to be with enrichment: lactose 10g/L, and peptone 5g/L, yeast powder 10g/L, sodium-chlor 3g/L, pH 7.2~7.5, and solid medium adds agar 20g/L.
Wherein, above-mentioned fungi selects for use enrichment to select substratum or slant medium formula optimization to be: murphy juice (potato 200g/L), and lactose 10g/L, agar 20g/L, natural pH, solid medium add agar 20g/L.
Wherein, the described culture condition in producing the enzymic fermentation nutrient solution of above-mentioned steps (4) preferably: bacterium was cultivated 16~18 hours in 37 ℃ of shaking tables; Fungi was cultivated 40~48 hours in 28 ℃ of shaking tables.
Wherein, the concentration of the described ONPG solution of above-mentioned steps (6) 2mmol/L preferably.
Wherein, the described Na of above-mentioned steps (7) 2CO 3Strength of solution is 0.5mol/L preferably.
Wherein, the above-mentioned damping fluid 50mmol/L potassium phosphate buffer of pH 6.5~7.5 preferably.
Wherein, above-mentioned damping fluid most preferably is the 50mmol/L potassium phosphate buffer of pH 7.0~7.5.
Wherein, the condition optimization of the described commentaries on classics glycosyl reaction of above-mentioned steps (10) is: 40~50 ℃ of temperature, change glycosyl reaction 6~8 hours.
Wherein, above-mentioned steps (10) also can select to change the oligose product of the active higher bacterial strain of glycosyl, (High Performance Liquid Chromatography, HPLC) bacterial strain that yield of oligosaccharide is the highest is determined in analysis and thin layer scanning analysis to carry out high performance liquid chromatography.
For the active high bacterial strain of the glycosyl transferred beta-galactosidase that filters out, can also make further strain identification, judge whether to be newfound glycosyl transferred beta-galactosidase bacteria strain.
The invention provides a kind of screening method of glycosyl transferred beta-galactosidase bacteria, can filter out glycosyl transferred beta-galactosidase bacteria from nature simple and effectively, and can obtain to change the active high beta-galactosidase bacteria of glycosyl, be the exploitation of industrial microorganism, provide new bacterial classification source in particular for the suitability for industrialized production oligomeric galactose.
Embodiment
Embodiment 1: screen glycosyl transferred beta-galactosidase bacteria from soil
1. can utilize the separation and purification of lactose for sole carbon source growth bacterial strain
The 10g soil sample is added enrichment culture in the nutrient solution that 100mL is sole carbon source with the lactose, nutrient solution is diluted to 10 with sterilized water -1, 10 -3, 10 -5, 10 -7Gradient is respectively got 200 μ L and is evenly coated on the lactose selection flat board.The bacteria screening flat board was in 37 ℃ of cultivations 24 hours, and the fungi screening flat board was cultivated 48~60 hours in 28 ℃.10 -5The bacterium colony kind that gradient plate grows is many, and is convenient to purifying.The different bacterium colony of picking form carries out separation and purification by plate streaking respectively, repeats 3 times.Isolated strains is carried out microscopy, determine purity: bacterium compares with streptococcus aureus (Staphylococcusaureus) and intestinal bacteria (Escherichia coli), carry out gramstaining, microscopy can be distinguished gram-positive microorganism and Gram-negative bacteria; Fungi is made the water logging sheet, and microscopy can be observed mycelia feature and spore producing method, and preliminary evaluation is to belonging to.The purifying strain bacterium that at last microscopy is obtained is saved in respectively on the test tube slant, 4 ℃ of storages.
Utilizing above-mentioned separation and purification process to obtain 15 strain bacterium altogether can be the sole carbon source growth with the lactose, wherein bacterium 9 strains, fungi 6 strains.15 strain bacterium are numbered respectively, bacterium be B1 ..., B9; Fungi be F1 ..., F6.
Above-mentioned bacteria screening selects substratum (also as slant medium) prescription to be with the bacterium enrichment: lactose 10g/L, and peptone 5g/L, yeast powder 10g/L, sodium-chlor 3g/L, pH 7.2~7.5, and solid medium adds agar 20g/L.
Above-mentioned fungi screening selects substratum (also as slant medium) prescription to be with enrichment: murphy juice (potato 200g/L), and lactose 10g/L, agar 20g/L, natural pH, solid medium add agar 20g/L.
2. produce the screening of beta-galactosidase enzymes bacterial strain
The 15 strain bacterium that above-mentioned separation is obtained are seeded to respectively in the 30mL product enzymic fermentation nutrient solution, and bacterium was cultivated 18 hours in 37 ℃ of shaking tables, and fungi was cultivated 40 hours in 28 ℃ of shaking tables, and shaking speed is 180 rev/mins.Bacterium yeast culture liquid is in 12,000 rev/mins of centrifugal 5 minutes acquisition mycetocytes; Mould obtains mycetocyte with filter paper (two circle board 101 fast qualitative filter paper) suction filtration.Measure mycetocyte beta-galactosidase enzymes hydrolytic activity then: with mycetocyte and beta-galactosidase enzymes hydrolysis substrate---o-NP-β-D-galactoside (o-nitrophenyl-β-D-galactopyranoside, ONPG) mixing is reacted, if ONPG is hydrolyzed, think that promptly this bacterium produces beta-galactosidase enzymes.
Get mycetocyte 50mg, add ONPG (colourless) the solution 450 μ L of 2mmol/L, 40 ℃ were reacted 10 minutes, added the Na of 1mL0.5mol/L 2CO 3The solution termination reaction, 12,000 rev/mins centrifugal 2 minutes.If it is yellow that supernatant liquor is, illustrate that former colourless ONPG has been hydrolyzed into the xanchromatic o-NP by beta-galactosidase enzymes, mycetocyte has the existence of beta-galactosidase enzymes.If supernatant liquor is surveyed OD 400, the enzyme that can be hydrolyzed is lived quantitatively.The unit of activity of enzyme regulation: the enzyme amount that discharges 1 μ mol o-NP with 1 minute hydrolysis ONPG is an enzyme activity unit.
Above-mentioned screening process obtains 9 strain bacterium altogether and produces beta-galactosidase enzymes, and wherein 5 strain bacteriums, 4 fungal strains are respectively B1, B2, B4, B5, B9, F1, F2, F3, F4.
Above-mentioned product enzymic fermentation culture medium prescription is: lactose 10g/L, peptone 5g/L, yeast powder 10g/L, CaCl 20.11g/L, MnSO 40.001g/L, MgSO 47H 2O 0.3g/L, KH 2PO 40.05g/L, FeSO 47H 2O 0.03g/L, pH 7.0~7.5 (bacterium) or pH 6.0~6.5 (fungi).
Grope through serial experiment, above-mentioned product enzymic fermentation substratum also can be reduced to following product enzymic fermentation culture medium prescription: lactose 10g/L, peptone 5g/L, yeast powder 10g/L, sodium-chlor 3g/L, pH 7.0~7.5 (bacterium) or pH 6.0~6.5 (fungi); Wherein, more preferably pH 7.2~7.5 (bacterium) or pH 6.2~6.5 (fungi) of described pH.
3. produce the screening of glycosyl transferred beta-galactosidase bacterial strain
The mycetocyte of above-mentioned 9 kinds of beta-galactosidase bacterias is made crude enzyme liquid, change the active screening of galactosyl.
Get the 50mg mycetocyte, be suspended in the potassium phosphate buffer of 50 μ L pH7.0,50mmol/L, after-20 ℃ of following temperature are freezing fully, put room temperature and thaw, repeat freeze thawing again 2 times, the gained suspension is the beta-galactosidase enzymes crude enzyme liquid.Get 100 μ L crude enzyme liquids, 30% (w/v) lactose solution that adds the preparation of 300 μ L pH7.0 potassium phosphate buffers, being divided into 2 equal portions reacts respectively at 40C, 50 ℃, bacterial reaction 4 hours, fungi reaction 8 hours, 12,000 rev/mins centrifugal 5 minutes, supernatant liquor promptly contains reaction product---oligomeric galactose.
Reaction product is carried out thin-layer chromatography, and (Thin-Layer Chromatography TLC) analyzes, and determines to change the glycosyl activity.TLC thin plate (Silica gel60, No.553, Merck) behind the point sample, at developing agent (propyl carbinol: ethanol: exhibition layer water=5: 3: 2), spray painting developer (3 of 20% sulphuric acid soln+0.5%, the 5-orcin), in 120 ℃ the baking 10 minutes, the colour developing of sugared spot according to its kind from pale brown look to intense violet color.If generated new oligosaccharides spot near the lactose spot, then the beta-galactosidase enzymes of Chan Shenging has the glycosyl of commentaries on classics activity; Do not change the glycosyl activity otherwise then do not exist.The oligosaccharides spot is big more, many more, illustrates that the commentaries on classics glycosyl activity of enzyme is strong more.
The result determines that 2 strain bacteriums (B1, B5) and 1 fungal strain (F3) have is changeed the glycosyl activity preferably.
The commentaries on classics glycosyl product of bacterial strain B1, B5 and F3 is carried out high performance liquid chromatography (High Performance LiquidChromatography, HPLC) analysis and thin layer scanning analysis, the yield of oligosaccharide of B1, B5, F3 bacterium is respectively 45.1%, 54.5%, 38.6%, and wherein the yield of oligosaccharide of B5 bacterium is the highest.
B1, B5 bacterium are accredited as enterobacter agglomerans (Enterobacter agglomerans), enterobacter cloacae (Enterobacter cloacae) respectively by 16S rDNA homologous sequence comparison and physio-biochemical characteristics; F3 is accredited as mould (Penicillum sp.) by morphological feature.At present not having enterobacter agglomerans and enterobacter cloacae beta-galactosidase enzymes in the world is the report of substrate catalytic production oligomeric galactose with the lactose.
Above-mentioned HPLC analyzes equipment used and condition: Tianjin, island (SHIMADZU) high performance liquid chromatograph; Tianjin, island RID-10A differential detector; BIO-RAD Aminex HPX-42C post (300mm * 7.8mm); Moving phase is tri-distilled water, and flow velocity is 0.2mL/min, 80 ℃ of column temperatures; Interpretation of result software is Class-VP6.0.Change the glycosyl product with 0.2 μ m membrane filtration after, be diluted to the sugar soln of 5% (w/v), sample introduction analysis.
Above-mentioned thin layer scanning is analyzed equipment used and condition: Tianjin, island (SHIMADZU) CS-9301 dual wavelength flying spot thin layer chromatography scanner, the detection wavelength is 550nm.Above-mentioned thin layer chromatography board is carried out scanning analysis.
Embodiment 2: screen glycosyl transferred beta-galactosidase bacteria from the milk slag
1. can utilize the separation and purification of lactose for sole carbon source growth bacterial strain
10g milk slag is added enrichment culture in the nutrient solution that 100mL is sole carbon source with the lactose, nutrient solution is diluted to 10 with sterilized water -2, 10 -4, 10 -6, 10 -8Gradient is respectively got 200 μ L and is evenly coated on the lactose selection flat board.The bacteria screening flat board was in 37 ℃ of cultivations 24 hours, and the fungi screening flat board was cultivated 60 hours in 28 ℃.10 -6The bacterium colony kind that gradient plate grows is many, and is convenient to purifying.The different bacterium colony of picking form carries out separation and purification by plate streaking respectively, repeats 3 times.Isolated strains is carried out microscopy, determine purity: bacterium compares with streptococcus aureus (Staphylococcusaureus) and intestinal bacteria (Escherichia coli), carry out gramstaining, microscopy can be distinguished gram-positive microorganism and Gram-negative bacteria; Fungi is made the water logging sheet, and microscopy can be observed mycelia feature and spore producing method, and preliminary evaluation is to belonging to.The purifying strain bacterium that at last microscopy is obtained is saved in respectively on the test tube slant, 4 ℃ of storages.
Utilizing above-mentioned separation and purification process to obtain 154 strain bacterium altogether can be sole carbon source growth, wherein 99 strain bacteriums and 55 fungal strains with the lactose.Be numbered respectively, bacterium be MB1 ..., MB99; Fungi be MF1 ..., MF55.
Above-mentioned bacteria screening selects substratum (also as slant medium) prescription to be with enrichment: lactose 10g/L, and peptone 5g/L, yeast powder 10g/L, NaCl 3g/L, pH 7.2~7.5, and solid medium adds agar 20g/L.
Above-mentioned fungi screening selects substratum (also as slant medium) prescription to be with enrichment: murphy juice (potato 200g/L), and lactose 10g/L, agar 20g/L, natural pH, solid medium add agar 20g/L.
2. produce the screening of beta-galactosidase enzymes bacterial strain
The 154 strain bacterium that above-mentioned separation is obtained are seeded to respectively in the 30mL product enzymic fermentation nutrient solution, and bacterium was cultivated 18 hours in 37 ℃ of shaking tables, and fungi was cultivated 40 hours in 28 ℃ of shaking tables, and shaking speed is 180 rev/mins.Bacterium and yeast culture liquid are in 12,000 rev/mins of centrifugal 5 minutes acquisition mycetocytes; Mould obtains mycetocyte with the filter paper suction filtration.Measuring mycetocyte beta-galactosidase enzymes hydrolytic activity then: with mycetocyte and beta-galactosidase enzymes hydrolysis substrate---ONPG mixes and reacts, if ONPG is hydrolyzed, thinks that promptly this bacterium produces beta-galactosidase.
Get mycetocyte 50mg, add the ONPG solution 450 μ L of 2mmol/L, 40 ℃ are reacted 10min, add the Na of 1mL0.5mol/L 2CO 3The solution termination reaction, 12,000 rev/mins centrifugal 2 minutes.If it is yellow that supernatant liquor is, illustrate that ONPG (colourless) has been hydrolyzed into the xanchromatic o-NP by beta-galactosidase enzymes, mycetocyte has the existence of beta-galactosidase enzymes.Supernatant is surveyed OD 400, can carry out quantitatively lytic enzyme work.The unit of activity of enzyme regulation: the enzyme amount that discharges 1 μ mol o-NP with 1 minute hydrolysis ONPG is an enzyme activity unit.
Above-mentioned screening process obtains 37 strain bacterium and produces beta-galactosidase enzymes, wherein 27 strain bacteriums and 10 fungal strains.
Above-mentioned product enzymic fermentation substratum: lactose 10g/L, peptone 5g/L, yeast powder 10g/L, CaCl 20.11g/L, MnSO 40.001g/L, MgSO 47H 2O 0.3g/L, KH 2PO 40.05g/L, FeSO 47H 2O 0.03g/L, pH 7.2~7.5 (bacterium) or pH 6.2~6.5 (fungi).
3. produce the screening of glycosyl transferred beta-galactosidase bacterial strain
The mycetocyte of above-mentioned 37 kinds of beta-galactosidase bacterias is made crude enzyme liquid, change the active screening of galactosyl.Get the 50mg mycetocyte, be suspended in the potassium phosphate buffer of 50 μ L pH7.0,50mmol/L, after freezing fully below-20 ℃, put room temperature and thaw, repeat freeze thawing again 2 times, the gained suspension is the beta-galactosidase enzymes crude enzyme liquid.Get 100 μ L crude enzyme liquids, 30% (w/v) lactose solution that adds the preparation of 300 μ L pH7.0 potassium phosphate buffers, being divided into 2 equal portions reacts respectively at 40 ℃, 50 ℃, bacterial reaction 4 hours, fungi reaction 8 hours, 12,000 rev/mins centrifugal 5 minutes, supernatant liquor promptly contains reaction product---oligomeric galactose.
Reaction product is carried out TLC analyze, determine to change the glycosyl activity.TLC thin plate (Silica gel60, No.553, Merck) behind the point sample, at developing agent (propyl carbinol: ethanol: exhibition layer water=5: 3: 2), spray painting developer (3 of 20% sulphuric acid soln+0.5%, the 5-orcin), in 120 ℃ the baking 10 minutes, the colour developing of sugared spot according to its kind from pale brown look to intense violet color.If generated new oligosaccharides spot near the lactose spot, then the beta-galactosidase enzymes of Chan Shenging has the glycosyl of commentaries on classics activity; Do not change the glycosyl activity otherwise then do not exist.The oligosaccharides spot is big more, many more, illustrates that the commentaries on classics glycosyl activity of enzyme is strong more.
The result determines that 12 strain bacterium have is changeed the glycosyl activity preferably, wherein 5 strain bacteriums and 7 fungal strains.
The commentaries on classics glycosyl product of above-mentioned 12 strain bacterium is carried out the HPLC analysis, and the result has the yield of oligosaccharide of 9 strain bacterium 30~35%; The yield of oligosaccharide of 3 strain bacterium (1 strain bacterium and 2 fungal strains) is numbered MB6, MF8, MF10 more than 40%, and yield of oligosaccharide is respectively 42.3%, 41.2%, 40.6%.
MB6, MF8, MF10 bacterium are accredited as respectively by morphological feature: spore production bacteria, candiyeast (Candida sp.), mould (Penicillum sp.).
Above-mentioned HPLC analysis and thin layer scanning analysis equipment used and condition are with embodiment 1.

Claims (9)

1. the screening method of a glycosyl transferred beta-galactosidase bacteria, form by following step:
(1) gets enrichment culture in the nutrient solution that the adding of bacterium sample is sole carbon source with the lactose, with sterilized water described nutrient solution is diluted to 10-1,10-3,10-5,10-7 gradient, respectively getting 200 μ L evenly coats on the lactose screening flat board, bacteria screening is dull and stereotyped selects 35~40 ℃ to cultivate 20~28 hours, and fungi screening is dull and stereotyped selects 26~30 ℃ to cultivate 48~72 hours;
Above-mentioned bacteria screening is selected substratum or slant medium with enrichment, and its prescription is: lactose 10 ± 2g/L, and peptone 5 ± 2g/L, yeast powder 10 ± 2g/L, sodium-chlor 3 ± 2g/L, pH 7.0~7.5, and solid medium adds agar 20 ± 2g/L;
Above-mentioned fungi screening is selected substratum or slant medium with enrichment, and its prescription is: murphy juice is potato 200 ± 2g/L wherein, lactose 10 ± 2g/L, agar 20 ± 2g/L, natural pH;
(2) after the cultivation, the different bacterium colony of picking form carries out separation and purification, triplicate by plate streaking respectively;
(3) isolated strains is carried out microscopy, determine purity: bacterium compares with streptococcus aureus (Staphylococcusaureus) and intestinal bacteria (Escherichia coli), carry out gramstaining, microscopy can be distinguished gram-positive microorganism and Gram-negative bacteria; Fungi is made the water logging sheet, and microscopy can be observed mycelia feature and spore producing method, and preliminary evaluation is to belonging to;
(4) the purifying bacterial strain that above-mentioned microscopy is obtained is inoculated in respectively and produces in the enzymic fermentation nutrient solution, and bacterium was cultivated 16~20 hours in 35~40 ℃ of shaking tables; Fungi was cultivated 40~50 hours in 26~30 ℃ of shaking tables, and shaking speed is 180 rev/mins;
Described product enzymic fermentation culture medium prescription is: lactose 10g/L, peptone 5g/L, yeast powder 10g/L, CaCl 20.11g/L, MnSO 40.001g/L, MgSO 47H 2O 0.3g/L, KH 2PO 40.05g/L, FeSO 47H 2O 0.03g/L, bacterium pH are 7.0~7.5, and fungi pH is 6.0~6.5;
(5) treat that above-mentioned cultivation reaches required bacterium amount after, with 12,000 rev/mins centrifugal 2~5 minutes, collect the bacterium or the yeast that produce in the enzymic fermentation nutrient solution; Obtain mycetocyte for mould with the filter paper suction filtration;
(6) with above-mentioned mycetocyte and beta-galactosidase enzymes hydrolysis substrate---o-NP-β-D-galactoside (o-nitrophenyl-β-D-galactopyranoside, ONPG) in w/v=mg/ μ L, press mycetocyte: the mixed of ONPG solution=1: 9,40 ℃ of reactions 10~15 minutes;
(7) add Na 2CO 3The solution termination reaction, with 12,000 rev/mins centrifugal 2~5 minutes, collect supernatant liquor;
(8) yellow if supernatant liquor is, illustrate that former colourless ONPG has been hydrolyzed into the xanchromatic o-NP by beta-galactosidase enzymes, prove that promptly this mycetocyte contains beta-galactosidase enzymes, be and produce the beta-galactosidase enzymes bacterial strain;
(9) with the mycetocyte of above-mentioned product beta-galactosidase enzymes bacterial strain, in w/v=mg/ μ L, in mycetocyte: the ratio of damping fluid=1: 1, mycetocyte is suspended from the damping fluid, after-20 ℃ of following temperature are freezing fully, put room temperature and thaw, repeat freeze thawing again 2~3 times, so the mycetocyte suspension is the beta-galactosidase enzymes crude enzyme liquid;
(10) with above-mentioned crude enzyme liquid in volume ratio, press crude enzyme liquid: the mixed of lactose solution=1: 3, change glycosyl reaction 4~10 hours in 40~60 ℃, wherein: lactose solution concentration is 30% percent weight in volume, solvent is above-mentioned damping fluid, after question response finishes, and 12,000 rev/min centrifugal 2~5 minutes, supernatant liquor promptly contains changes glycosyl reaction product oligomeric galactose;
(11) above-mentioned reaction product is carried out thin-layer chromatography (Thin-Layer Chromatography, TLC) analyze, judge that enzyme changes the glycosyl activity, wherein, developing agent is a propyl carbinol: ethanol: water=5: 3: 2, developer are 3 of 20% sulphuric acid soln+0.5%, the 5-orcin, in 120 ℃ the baking 10 minutes, the colour developing of sugared spot according to its kind from pale brown look to intense violet color; If generated new oligosaccharides spot near the lactose spot, then the beta-galactosidase enzymes of Chan Shenging has the glycosyl of commentaries on classics activity; Do not change the glycosyl activity otherwise then do not exist;
(12) big more, many more with the oligosaccharides spot, illustrate promptly that the commentaries on classics glycosyl activity of enzyme is strong more and be foundation that the active higher bacterial strain of glycosyl transferred beta-galactosidase is produced in screening.
2. the screening method of glycosyl transferred beta-galactosidase bacteria as claimed in claim 1 is characterized in that, bacteria screening is dull and stereotyped selects 37 ℃ to cultivate 24~26 hours, and fungi screening is dull and stereotyped selects 28 ℃ to cultivate 48~60 hours.
3. the screening method of glycosyl transferred beta-galactosidase bacteria as claimed in claim 1, it is characterized in that, described bacteria screening selects substratum or slant culture based formulas to be with enrichment: lactose 10g/L, peptone 5g/L, yeast powder 10g/L, sodium-chlor 3g/L, pH 7.2~7.5, and solid medium adds agar 20g/L; Fungi selects for use enrichment to select substratum or slant medium formula optimization to be: murphy juice is potato 200g/L wherein, lactose 10g/L, and agar 20g/L, natural pH, solid medium add agar 20g/L.
4. the screening method of glycosyl transferred beta-galactosidase bacteria as claimed in claim 1 is characterized in that, the described culture condition in producing the enzymic fermentation nutrient solution of step (4) is: bacterium was cultivated 16~18 hours in 37 ℃ of shaking tables; Fungi was cultivated 40~48 hours in 28 ℃ of shaking tables.
5. the screening method of glycosyl transferred beta-galactosidase bacteria as claimed in claim 1 is characterized in that, the concentration of the described ONPG solution of step (6) is 2mmol/L.
6. the screening method of glycosyl transferred beta-galactosidase bacteria as claimed in claim 1 is characterized in that, the described Na of step (7) 2CO 3Strength of solution is 0.5mol/L.
7. the screening method of glycosyl transferred beta-galactosidase bacteria as claimed in claim 1 is characterized in that, described damping fluid is the 50mmol/L potassium phosphate buffer of pH 6.5~7.5.
8. the screening method of glycosyl transferred beta-galactosidase bacteria as claimed in claim 7 is characterized in that, described damping fluid is the 50mmol/L potassium phosphate buffer of pH 7.0~7.5.
9. the screening method of glycosyl transferred beta-galactosidase bacteria as claimed in claim 1 is characterized in that, the condition of the described commentaries on classics glycosyl reaction of step (10) is: 40~50 ℃ of temperature, change glycosyl reaction 4~8 hours.
CNB2005100440962A 2005-07-21 2005-07-21 Glycosyl transferred beta-galactosidase bacteria screening method Expired - Fee Related CN1313599C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CNB2005100440962A CN1313599C (en) 2005-07-21 2005-07-21 Glycosyl transferred beta-galactosidase bacteria screening method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CNB2005100440962A CN1313599C (en) 2005-07-21 2005-07-21 Glycosyl transferred beta-galactosidase bacteria screening method

Publications (2)

Publication Number Publication Date
CN1737118A true CN1737118A (en) 2006-02-22
CN1313599C CN1313599C (en) 2007-05-02

Family

ID=36080067

Family Applications (1)

Application Number Title Priority Date Filing Date
CNB2005100440962A Expired - Fee Related CN1313599C (en) 2005-07-21 2005-07-21 Glycosyl transferred beta-galactosidase bacteria screening method

Country Status (1)

Country Link
CN (1) CN1313599C (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102433291A (en) * 2012-01-16 2012-05-02 江南大学 Strain for producing beta-galactosidase and method for producing galacto-oligosaccharide by using beta-galactosidase
CN104764739A (en) * 2014-01-08 2015-07-08 中国科学院理化技术研究所 Method for detecting biotoxicity based on bacteria with beta-galactosidase

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6476209B1 (en) * 2000-11-28 2002-11-05 Genesis Research & Development Corporation Ltd. Polynucleotides, materials incorporating them, and methods for using them

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102433291A (en) * 2012-01-16 2012-05-02 江南大学 Strain for producing beta-galactosidase and method for producing galacto-oligosaccharide by using beta-galactosidase
CN104764739A (en) * 2014-01-08 2015-07-08 中国科学院理化技术研究所 Method for detecting biotoxicity based on bacteria with beta-galactosidase

Also Published As

Publication number Publication date
CN1313599C (en) 2007-05-02

Similar Documents

Publication Publication Date Title
CN1737132A (en) Method for quick preparing glycosyl transferred beta-galactosidase
Rajagopal et al. Systematic characterization of potential cellulolytic marine actinobacteria Actinoalloteichus sp. MHA15
CN104911125A (en) Chitosanase production strain and application thereof
CN1295344C (en) Screening method for phophonomycin biological conversion strain
CN1769425A (en) Bifidobacteria exocellular polysaccharide and its production method and special purpose production strain
CN118185841B (en) Vibrio cellulosae strain NN19 and application thereof
Mishra et al. Biosynthesis and hyper production of pullulan by a newly isolated strain of Aspergillus japonicus-VIT-SB1
CN1313599C (en) Glycosyl transferred beta-galactosidase bacteria screening method
El-Sayed et al. Optimization, purification and physicochemical characterization of curdlan produced by Paenibacillus sp. strain NBR-10
CN100347290C (en) Producing microorganism for trans-glycosylation beta-galactosidase
CN113265337A (en) Marine aspergillus versicolor and isolated culture method and application thereof
CN103146595B (en) Bacillus subtilis and method for fermentation production of D- ribose
Islam et al. Determination of alpha-amylase activity of Streptomyces spp isolated from Bangladeshi soils
CN1948500A (en) Preparation method of functional sweetener D-tatai sugar
CN113564079A (en) Paenibacillus polymyxa for producing sucrose phosphorylase and application thereof
CN110092758B (en) Novel alkaloid compound and wart spore strain for preparing compound by fermentation
JP4395380B2 (en) Cyclodextran high-producing microorganism and method for producing cyclodextran using the same
KR20010083600A (en) Process for Preparing Pullulan Employing Waste Materials Containing High Concentration of Sugars from Food-processing Industry
CN1188527C (en) Process for biotransformation of colchicone compounds into the correspoonding 3-o-glycosyl derivatives
JP2010119321A (en) Method for producing sugar alcohol
CN101054561A (en) Microorganism capable of hydrolyzing glycosyl to hydroxyl and application thereof
CN103740610B (en) Streptococcus AUH-JLD109 and application thereof in naringenin biosynthesis
CN100392066C (en) Gluconobacter and its use
CN117511806B (en) Geobacillus saccharophilus B37 and application thereof
Beshay et al. Optimization of submerged culture conditions for exo-polysaccharides production by Streptomyces Nasri-UV 135 in bioreactor

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20070502

Termination date: 20140721

EXPY Termination of patent right or utility model