25 September 2017, Volume 37 Issue 9

    

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  The Interaction Study Between Human Grx3 Protein and Transcription Factor p65

  HU Ke-yue, CHENG Ning-hui, WANG Xin-quan

  China Biotechnology. 2017, 37(9): 1-6. https://doi.org/10.13523/j.cb.20170901

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  Oxidation-reduction system exists in almost all organisms,and thiol-redox enzymes play a very important part in the oxidation-reduction system. Thiol-redox enzymes regulate the conversion between thiol group and disulfide bond. Thiol-redox enzymes exist in both glutaredoxins system and thioredoxins system in human body. Our target protein Grx3 is one of the most important role in glutaredoxins system. p65(RELA) a very important protein in human body which has a very close relation with inflammatory reaction regulates the NF-κB signal pathway,it almost control all of the cascade reaction of NF-κB signal pathway,while other studies has shown that Grx3 has a significant influence on NF-κB signal pathway. There is a connection between p65 and Grx3 in vivo environment by colocalisationexperiment and p65 and Grx3 protein purify from E.coli can crosslink in a specific in vitro environment which provide a significant proof of interaction between Grx3 and p65 in vitro environment and explains how Grx3 get involved in the NF-κB signal pathway as while.
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  Soluble Expression of Human Leukemia Inhibitory Factor in Prokaryotic Cells and Its Purification

  ZHANG He-ming, CAI Chu-fan, LIU Yang, GAN Long-zhan, JIAO Xue-miao, TIAN Yong-qiang

  China Biotechnology. 2017, 37(9): 7-14. https://doi.org/10.13523/j.cb.20170902

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  Numerous studies have demonstrated that leukemia inhibitory factor (LIF) is one of the most important polyfunctional cytokine, hLIF is a pleiotropic cytokine with multiple effects on different types of cells and tissues, its unique biological characteristics make it widely used. The homemade hLIF which is biologically active is viesented, hLIF gene was cloned into pET32a, and it successfully expressed the soluble recombinant protein in E. coli using the thioredoxin (Trx) protein as a fusion partner. After purification based on membrane adsorber technology, the fusion protein was cleaved using EK protease. Released, soluble hLIF was subsequently purified by cation exchange, The samples analysis by SDS-PAGE and Western blot. This procedure yields up to 4.75mg rhLIF with 98.1% purity. Functional analysis of the purified rhLIF by murine myeloblastic leukemia M1 cell proliferation assay demonstrates biological activity that is similar and comparable to that of hLIF, and with the EC₅₀ of 6ng/ml and the corresponding specific activity of 0.5×10⁷ IU/mg.
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  Expression, Purification and Identification of Thymidine Kinase 1 Recombinant Protein

  WANG Yun-long, ZHAO Er-xia, LI Yu-lin

  China Biotechnology. 2017, 37(9): 15-22. https://doi.org/10.13523/j.cb.20170903

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  In order to obtain the TK1 recombinant protein with immunogenicity. The target gene was amplified by PCR, double digested with XhoI/EcoRI restriction endonuclease, linked to the expression vector pET32a, and then transferred into competent cells to prepare BL21-pET32a-TK1 recombinant strain. The TK1 protein was expressed by IPTG induced BL21-pET32a-TK1 recombinant bacteria and optimized from IPTG concentration, culture temperature and time. The expression level of recombinant protein TK1 was tested by SDS-PAGE, and determined the optimal induction conditions. The expressed product was purified by nickel ion affinity chromatography, used SDS-PAGE to detect the purity of the target protein, and the antigenicity of the target protein was detected by Western blot. Used the obtained TK1 recombinant protein to immunize the mice, took the spleen cells of the best immune effect mice to fuse with SP2/0. Screened monoclonal cell lines that secreting specific antibodies stably. And then detected the subtype and specificity of antibody. The experimental results showed that the condition of 37℃,when the concentration of IPTG was 0.2mmol/L and induced for 6h meanwhile, the recombinant protein expression quantity of TK1 was highest. Under the condition of nickel ion affinity chromatography gradient elution, in 80mmol/L imidazole, the content of recombinant protein TK1 was the highest purity. It was 87.3%. After concentrating, the protein concentration was 5.96mg/ml. With indirect ELISA detection,10 strains of cell that can stable secretion specificity TK1 antibody by hybridoma technology were obtained. this suggests that TK1 recombinant protein have immunogenicity. It can provide the material base for the clinical research of related tumors.
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  Effect of D97N Mutation on Proton Transport and Energy Conversion in the Photoreceptor Archaerhodopsin 4

  WANG Juan, GAO Yu-jiao, SUN Chao, ZHAO Xin

  China Biotechnology. 2017, 37(9): 23-30. https://doi.org/10.13523/j.cb.20170904

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  Archaerhodopsin 4 (aR4) is a newly discovered photosensitive retinal protein from the claret membrane of Halobacterium species xz515. It functions as a proton pump similar to bacteriorhodopsin (bR) but with an opposite temporal order of proton uptake and release at neutral pH. Aspartic acid 97 (D97) is one of the key residues as the proton donor during the photocycle in aR4. Its function on the photocycle, the proton pump function and the energy conversion is very important for a deep understanding of the relationships between aR4 structure and function, especially with proton release and uptake order. Single mutation of D96N of bR and D97N of aR4 have been successfully constructed by combining site-directed mutagenesis with heterologous expression in Halobacterium species L33. The influences of mutations on the retinal binding pocket, transient kinetic change of the M state and O state, and the ATP conversion efficiency have been studied by UV-VIS and flashlight induced kinetic absorption change spectroscopy. The results show that D97N mutation in aR4 does not affect the UV absorption of the retinal chromophore, but results in a significant prolongation of the M state, a greatly weakened proton pump, and a decreased ATP formation efficiency. This indicates a different function of D97 in aR4 than the same type residue D96 in bR due to a more hydrophobic environment along the proton translocation channel from D97 to the retinal chromophore.
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  Algal Polysaccharides Inhibits Proliferation and Migration of Liver Cancer Cell Hep3B Via Down-regulation of EMP Pathway

  FENG Yuan, TANG Yun, XU Lei, TAN Hai-gang

  China Biotechnology. 2017, 37(9): 31-40. https://doi.org/10.13523/j.cb.20170905

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  Objective:To investigate the effort of algal polysaccharides(AP) on the ability of proliferation and migration in the liver cancer cell line Hep3B and potential mechanism which may provide a new idea for treatment of liver cancer.Methhods:①Four different cell lines were selected to compare the metabolic levels of embden-meyerhof-parnas(EMP) pathway in normal cells and cancer cells.②To detect the EMP metabolic levels changes in Hep3B with AP treatment.③MTT, qPCR and Transwell were used to measure the ability of cell proliferation,EMT marker and cell migration respectively in Hep3B cell with AP treatment.④Measured the ability of cell viability,proliferation and EMT Pathway with inhibitor:3-bromopyruvate(3-BrPA). ⑤Measured EMP levels and Akt signal pathway changes with AP or 3-BrPA treatment. ⑥Detected Akt signal pathway,cell viability and migration changes with AP and 3-BrPA treatment. Result:①The metabolic levels of EMP in cancer cells(Hep3B,HeLa,SW480)are higher than normal cell(HL02).Hep3B cell EMP metabolic level is the highest in three cancer cell lines. ②AP down regulated metabolic levels in Hep3B cell and it was concentration-dependent. ③AP inhibited the ability of proliferation and migration in Hep3B and down regulated the EMT progress. ④3-BrPA inhibited HK activity and down regulated the cell viability rate and migration ability compared with control group(P<0.01). ⑤AP and 3-BrPA both down regulated the EMP levels and inhibited Akt signal pathway. ⑥In AP + 3-BrPA group, HK activity was depressed obviously compared with AP group, and cell viability and wound healing rate were decreased seriously. Conclusion:The metabolic level of EMP pathway in Hep3B is much higher than normal cell. AP could down regulated Hep3B cell EMP metabolism level. Low metabolism levels of EMP could inhibit the proliferation and migration of Hep3B via down-regulation of EMT progress and Akt signaling pathway. When Hep3B was co-treated with AP and 3-BrPA,the cell ability and migration ability were depressed more obviously than only AP treatment. These data show AP therapy was effective on liver cancer cell Hep3B.
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  Metabolic Characteristics of Intracellular Trehalose Accumulation in Zygosaccharomyces rouxii

  LIU Cui-cui, HU Meng-die, WANG Zhi, DAI Jun, YAO Juan, LI Pei, LI Zhi-jun, CHEN Xiong, LI Xin

  China Biotechnology. 2017, 37(9): 41-47. https://doi.org/10.13523/j.cb.20170906

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  Trehalose synthesis is an important pathway to protect cell against environmental stress. The metabolic characteristics of Zygosaccharomyces rouxii CCTCC M2013310 under three different trehalose fermentation control strategies included batch, fed-batch and fed-batch conbined control temperature in 10L fermentation tank are studied. The results from chromatographic analysis show that lactic acid, pyruvate and α-ketoglutaric acid are significantly affected by different fermentation modes. However, there is no significant difference between the total content of glutamic acid and glutamine in the three fermentation control process. These results show that the accumulation of intracellular trehalose is effected by the cell reduction force balance pathway and the metabolic regulation of carbon and nitrogen metabolism. The results provid a new idea for the metabolic engineering of Z. rouxii CCTCC M2013310 to make the high concentration of endogenous trehalose yeast cell.
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  Establishment and Application of Multiplex Fluorescent Real-time PCR for Detecting Six Kinds of Animal Derived Materials

  FU Li-wen, ZHANG Yu, YI Han, LI Xue, ZHU Nai-shuo

  China Biotechnology. 2017, 37(9): 48-59. https://doi.org/10.13523/j.cb.20170907

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  Objective:To establish a highly efficient method for simutaneously detecting pig, bovine, sheep, chicken, duck and goose derived materials in animal products by use of the multiplex fluorescent real-time quantitative PCR(qPCR). Methods:The species-specific primers and probes for detection of beta-actin (actb) genes of pig, bovine, chicken, duck and goose, and the prolactin receptor gene of sheep in multiplex fluorescent real-time quantitative PCR assay were designed. Total DNA as templates were extracted respectively from the six kinds of animal materials. The specificity and sensitivity of these primer pairs and probes were separately confirmed using simplex real-time qPCR analysis. Six pairs of primers and six fluorescent probes were mixed up with the above 6 kinds of animal templates. And the most effective reaction system and condition for multiplex(hexa-plex) qPCR method were obtained experimentlly after lots of tests and optimization. The specificity, sensitivity and accuracy of this assay were evaluated. Results:The limits of detection (LOD) of the assay were 0.049ng, 0.048ng, 0.085ng, 0.13ng, 0.162ng, 0.074ng DNA for pig, bovine, sheep, chicken, duck and goose, respectively (50μl qPCR reaction system), and the amplification results of other animals were all negative. A total of 200 specimens tested by the multiplex qPCR method one more showed its accuracy, precision and high efficiency. Conclusions:The developed multiplex fluorescent real-time quantitative PCR method was a rapid, specific, sensitive and efficacious detection assay for pig, bovine, sheep, chicken, duck and goose derived materials in animal products, and was applicable to identifications in feed stuff, meat, milk, pelt and grease, etc.
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  Construction of a Neotype Controllability Magnetic Targeting Restructuring Truncated Tissue Factor

  CHEN Xiao-li, ZOU Ming-yuan, XIE Xin, WANG Sheng-yu, WU Ting, SU Jin-hua

  China Biotechnology. 2017, 37(9): 60-64. https://doi.org/10.13523/j.cb.20170908

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  Objective:To establish a neotype controllability magnetic targeting restructuring truncated tissue factor s for establish animal models of thrombosis. Methods:Magnetic nanoparticles (MNPs) were prepared by chemical coprecipitation, and employed the superconducting quantum interference device to characterized the MNPs magnetization. The truncated tissue factor (tTF) were expressed efficiently in E.coli and purification by gene engineering technology. MNPs conjugated the tTF by glutaraldehyde to compose MNPs-tTF. In vitro analysis the effects of magnetic targeting and blood coagulation of MNPs-tTF. Result:The magnetic targeting restructuring truncated tissue factor composites were build successfully. They are reserve efficient coagulation effect and magnetic targeted ability in vitro. Conclusion:We have successfully prepared magnetic targeting thrombin system MNPs-tTF have been successfully prepared, which maybe provide a basis for developing the establish animal models of thrombosis.
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  Elevated Temperature Induced Acceleration of Electrophoretic Tissue Clearing Process of Rat Liver Tissue

  YUAN Xiao-chuan, LIAN Fang, ZHAO Yin-nong, CHEN Chuang, HUANG Shan, LI Ke-zhi, ZENG Ai-ping, HE Jian-bo, WU Guo-bin

  China Biotechnology. 2017, 37(9): 65-70. https://doi.org/10.13523/j.cb.20170909

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  Objective:CLARIT is a morphological technique that produces structurally intact, yet optically transparent tissue, which has important applications in nervous system structure and function investigations. However in other organs, especially liver tissue, the researches are not comprehensive. Since the lipid in liver tissue is difficult to clear. The protocol is aim to make this process faster and easier. Method:The rat livers are fixed with hydrogel and cut into 1mm slices. The control group is cleared with passive method. On the other side, the experimental group is dealt with electrophoretic tissue clearing and elevate temperature as well to find the optimum temperature for the liver tissue clearing. Results:Under the condition of 12V 37℃,the experimental group become transparent after 48h electrophoresis, the relative-transparency is changeless when run with another 48h electrophoresis. If elevate the temperature of electrophoresis, after 48h basal electrophoresis (12V 37℃), the relative -transparency can be further improved. Conclusion:To create extremely clear liver tissue,the best electrophoretic tissue clearing procedure is to run the samples at 12V 37℃ for 48h followed by more 48h with the temperature increased to 52℃.
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  Metabolic Engineering of Saccharomyces cerevisiae for Production of 8-Dimenthylally Naringenin

  LI Bo, LIANG Nan, LIU Duo, LIU Hong, WANG Ying, XIAO Wen-hai, YAO Ming-dong, YUAN Ying-jin

  China Biotechnology. 2017, 37(9): 71-81. https://doi.org/10.13523/j.cb.20170910

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  8-dimenthylallynaringenin(8DN) is the important precursor for the flavonoids medicine Icaritin, which has wide applications in pharmaceutical area. Due to the complexity of its biosynthetic pathway and related genes, main attentions were paied to biotransfering by procursor (like naringenin or isoxanthohumol) feeding. To date, no report about de novo biosynthesis of 8DN has been uncovered. In present study, in order to realize 8DN production in Saccharomyces cerevisiae, four key genes involved in naringenin biosynthesis, TAL,4CL,CHS and CHI from different species, were combinatorially screened, obtaining 30 naringenin producing strains, in which significant production variation ranged from 0.37mg/L to 22.34mg/L. Furthermore, the best combination of TAL,4CL,CHS and CHI genes were integrated into chromosome for better genetic stability by delta integration, generating strain SyBE_Sc02050031. Subsequently, prenyltransferase gene (N8DT) from Sophora flavescens incorporated with multicopy plasmid was introduced into SyBE_Sc02050031 (gaining strain SyBE_Sc02050032) and a titer of 8DN at 36.7μg/L in shaking flask was observed accordingly, indicating de novo biosynthesis of 8DN in yeast was successfully achieved. In addition, truncation tailoring strategy was explored to improve the catalysis function of N8DT, leading to 8DN production (up to 52.6μg/L) increasing by 44% compared to that in strain SyBE_Sc02050032. de novo biosynthesis of 8DN in microbes is firstly accomplished, which provides a good reference for microbial production of other natural flavonoids.
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  Modifiation of Cytochrome c at the Level of Lysine Residues Mediated by Microbial Transglutaminase

  ZHANG Chen, CHEN Shao-hua, WU Wen-qian, ZHOU Jian-qin

  China Biotechnology. 2017, 37(9): 82-88. https://doi.org/10.13523/j.cb.20170911

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  Experiments were carried out to investigate the possibilities of site specific PEGylation of therapeutic proteins (cytochrome c, Cyt c) catalyzed by mTG.Then reaction conditions were optimized and the properties of the PEGylated Cyt c were explored. CBZ-QG-mPEG was successfully synthesized by introducing CBZ-QG into methoxypolyethylene glycol amine (mPEG-NH₂) and could act as the acyl donor of mTG.The possibilities of mPEG-NH₂ acting as an amino donor or CBZ-QG-mPEGacting as an acyl donor to modify Cyt c catalyzed by mTG were investigated. CBZ-QG-mPEG was coupled to the specific Lys residue of Cyt c catalyzed by mTG.The optimized PEGylationconditions were as follows:37℃, pH 8.0, mTG 1.0mg/ml, reaction time 2h. The PEGylated Cyt c exhibited better thermal stability and pH stability than the native Cyt c. Only one specific Lys residue of Cyt c was PEGylated catalyzed by mTG, while several Lys residues of Cyt c were conjugated with mPEG-SPA by using the chemical method, which leading to the heterogeneity of the derivatives. The prominent advantage of mTG-mediated catalysis is its highsite specificity and thus homogeneity.Here, the mTG-mediated PEGylation of proteins at the level of lysine (Lys) residues was developed, which overcome the random modification of Lys residues by the chemical method andwas expected to be generally applied to protein modification.
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  Construction and Optimization of p-coumaric Acid Producing Saccharomyces cerevisiae

  ZHANG Wei, LIU Duo, LI Bing-zhi, YUAN Ying-jin

  China Biotechnology. 2017, 37(9): 89-97. https://doi.org/10.13523/j.cb.20170912

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  p-coumaric acid is widely used in bio-pharmaceutical, cosmetics and food industry as a very important precursor compound of phenylpropanoids, stilbenes and flavonoids. Saccharomyces cerevisiae was used as the host cell to synthesize p-coumaric acid with the methods of synthetic biology. It was demonstrated that the multi-copies plasmid harbored TAL showed a larger accumulation of p-coumaric acid; meanwhile, to eliminate the feedback inhibition of L-tyrosine, specific amino acid mutation Aro4p^K229L and Aro7p^G141S was obtained. The relevant mutated gene was integrated into yeast genome using delta site integration. 24 strains were picked out to verify the production of p-coumaric acid, the different yield between the highest strain and the lowest strain was 28.87mg/L. To strength the metabolic flux to p-coumaric, gene ARO10 and PDC5 which involved in the biosynthesis of byproduct aromatic alcohols were knocked out. Production of p-coumaric acid in strain with two gene knock out was improved to 87.56mg/L, 2.05-fold to the control one. Furthermore, when 1mmol/L L-tyrosine was added, the production of p-coumaric acid arrived the peak, about (174.57±0.30)mg/L. The p-coumaric acid over-producing S. cerevisiae using the synthetic biology method as well as lay a foundation of the biosynthesis of subsequent stilbenes and flavonoids has been successfuly constructed.
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  Extraction of Camelina Seed Oil Body and Analysis of Stability

  GAO Hong-tao, GUO Xiao-wei, SUN Dan, XIE Chang-rui, WANG Fa-wei, LI Hai-yan

  China Biotechnology. 2017, 37(9): 98-104. https://doi.org/10.13523/j.cb.20170913

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  Oil bodies are specialized organelles found regularly in plant oil seeds which save as lipid storage compartment. Triacylglycerols (TAG) are present in these small discrete intracellular organelles and oil bodies was surrounded by a monolayer phospholipids embedded with some specific proteins. The oil body can be applied to the food and pharmaceutical industry by the stable structure of against stress environment. Extraction efficiency camelina oil body was compared under the different method and stability was investigated including that the different pH, NaCl concentration conditions of camelina oil.The rate of extracted for oil bodies was up to 17% and uniform of dispersion be proved. The stability of oil bodies decreased with the increase of NaCl concentration; the oil bodies stably distributed in 8 ≤ pH ≤ 10 and the oil bodies' stability decreased obviously when pH value was between 4 and 7.The temperature and NaCl concentration almost had no effects on the oil bodies' stability.
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  Genome Shuffling Enhances Transglutaminase Production of Streptomyces mobaraensis

  SONG Jia-wen, TIAN Su, ZHANG Yu-ru, WANG Zhi-zhen, CHANG Zhong-yi, GAO Hong-liang, BU Guo-jian, JIN Ming-fei

  China Biotechnology. 2017, 37(9): 105-111. https://doi.org/10.13523/j.cb.20170914

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  Transglutaminase can catalyze Trans-phosphatidylation reaction, and is widely used in food industry. But the production of transglutaminase cannot meet the requirement of industrial production. Nowadays, random mutagenesis is the most frequent but inefficiency method to improve transglutaminase production. Transglutaminase production of Streptomyces mobaraensis is enhanced by genome shuffling. With 96-well plates high-throughput screening, the time and work are reduced. Firstly, protoplasts presentation conditions are optimized. The optimization conditions are treating mycelium by 6mg/ml lysozyme solution for 2 hours. Protoplasts are inactivated by UV illumination for 2 minutes and water-bath in 60℃ for 40min. Then fusants are picked up regenerating in regeneration medium and then screened by 96-well plates high-throughput screening and verified the high-production strains by fermentation in shaking flask. After two rounds of genome shuffling, a strain can produce TGase 65.5% higher than incipient strain is obtained and the production reaches 7.12U/ml.
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  Advances in Stem Cell 3D Scaffolds

  XU Zhu, ZHUGE Qi-chuan, HUANG Li-jie

  China Biotechnology. 2017, 37(9): 112-117. https://doi.org/10.13523/j.cb.20170915

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  Stem cells are characterized by the capacity of self-renewing and umlimited proliferation and differentiation. They can differentiate into specialized cells under different culture or induced conditions. At present, with the development of medical treatment and stem cell research, it is found that stem cells can be used for the treatment of many diseases. The clinical application of stem cells is in a vast need. However, stem cell transplantation efficiency is very low in vivo. It is still need to figure out the method of stem cells expansion, stable proliferation and differentiation. Currently,the main culture method of the stem cells is still 2D culture. 2D culture can not simulate the 3D microenvironment in the body, and the reproductive efficiency is low. There are emerging results to overcome the limition of 2D culture method by the experts. Here the development and application of 3D culture technologies of stem cells were reviewed.
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  Progress on High Efficient Expression and Application of Lysostaphin

  WANG Xi, CHEN Xi-ming, PU Tong-liang

  China Biotechnology. 2017, 37(9): 118-125. https://doi.org/10.13523/j.cb.20170916

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  Lysostaphin(Lys) is usually exogenously expressed in varieties of cells or organisms with gene cloning technology. Lys is a Zn²⁺ metalloenzyme and a glycylglycinen endopeptidase specific to the pentaglycine cross-bridges of peptidoglycan in the cell walls of Staphylococcus aureus, especially, methicillin-resistant S. aureus(MRSA), then showing an unique bacteriolytic activities. As a kind of efficient antibacterial agent, it has enormous application potentialities in the fields of veterinary drugs and clinical applications. It was reviewed the origins and lysing mechanism of the Lys, the varieties of exogenously gene expression systems. And the developmental situation and prospects of Lys applications were also discussed.
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  Devolopment of Regulation of Protein Lysine Acetylation on Intermediate Metabolism

  LAI Mu-lan, CHEN Xie-lan

  China Biotechnology. 2017, 37(9): 126-133. https://doi.org/10.13523/j.cb.20170917

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  A large number of lysine acetylation exist in the intermediate metabolic enzymes of life activities. The reversible lysine acetylation at specific sites of protein can regulte various kinds of intracellula metabolic pathways. Thus, the research of lysine acetylation of intermediate metabolic enzymes currently becomes a hotspot. The paper reviews the research progress of lysine acetylation of intermediate metabolic enzymes and summarizes several typical reversible lysine acetylation of intermediate metabolic enzymes, their distribution sites and the important regulatory role in the intermediate metabolic pathways, which provide a reference for futher study of protein acetylation.
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  Progress of Biosynthesis of Sophorolipids and Its Derivatives Production in Starmerella bombicola

  ZHANG Ya-guang, ZHANG Chuan-bo, LU Wen-yu

  China Biotechnology. 2017, 37(9): 134-140. https://doi.org/10.13523/j.cb.20170918

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  Sophorolipids, which is a kind of extracellular products, was produced by Starmerella bombicola under aerobic condition. As the member of biosurfactants, sophorolipids has shown excellent surface activity, biodegrade ability, low ecotoxicity and biocompatibility. Research progress of biosynthesis of sophorolipids is summarized, including metabolic pathway, key enzymes and genetic engineering of S. bombicola. Basic problems on efficient synthesis of sophorolipids in S. bombicola are discussed and a prospect of using S. bombicola as a new chassis for sophorolipids biosynthesis is analyzed.
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  Research Progress on Cloning, Expression,Immobilization and Molecular Modification of Nitrilase

  LI Ji-bin, CHEN Zhi, CHEN Hua-you

  China Biotechnology. 2017, 37(9): 141-147. https://doi.org/10.13523/j.cb.20170919

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  With the rapid development in genetic engineering technology, the analysis of the nitrilase gene from different strains, was cloned in the expression strain, to construct an efficient and stable genetically engineered bacteria. The molecular modification of the nitrilase could significantly improve the activity stability, substrate tolerance and substrate specificity of the enzyme, which make possible the use of nitrile hydrolase in the industrial applications.The origin, structure, catalytic mechanism, clonal expression, immobilization, molecular modification and prospects of nitrilase were reviewed. And it demonstrate important guidelines for the significance of nitrilase research.