Table of Content

• 
• Current Biotechnology
  Volume 12 Issue 2 25 March 2022

Reviews

• Research Advances in Protein Interactions Based on Mass Spectrometry
• Ruixue SUN, Wei MI, Zihong YE
• 2022, 12(2):  161-167.  DOI: 10.19586/j.2095-2341.2021.0137
• Abstract ( ) HTML ( ) PDF (497KB)( )

As the executor of life activities， the protein function is often reflected in the interaction with other proteins. The study of protein-protein interaction is of great significance for people to understand the prevention of infectious diseases， targeted treatment of multi-gene diseases， and elucidate the molecular mechanism of protein and various complex life phenomena. At present， a variety of techniques have been used to study protein-protein interactions. The difficulty lies in real-time capture of transient or weak protein-protein interactions， mass spectrometry （MS） can solve this difficulty to some extent. Because mass spectrometry can be used to study simple protein complexes and large-scale proteome experiments， the study of protein interactions based on mass spectrometry has been increasingly applied in scientific research. In this paper， the research progress of protein-protein interaction detection methods was reviewed， and the advantages and disadvantages of hydrogen deuterium exchange mass spectrometry and chemical crosslinking mass spectrometry and their applications were emphasized. Finally， the research on protein-protein interaction based on mass spectrometry was summarized and prospected， which aimed to provide reference for further research.

• Research Progress of Riboswitch Biosensors for Small Molecule Target
• Yifan WU, Shenghao LIN, Wentao XU
• 2022, 12(2):  168-175.  DOI: 10.19586/j.2095-2341.2021.0140
• Abstract ( ) HTML ( ) PDF (857KB)( )

There are many kinds of small molecule compounds， and play key roles in many biological processes， which has important detection significance and value. The development of its rapid and sensitive visual detection technology is a research hotspot at present. Biosensor based on riboswitch provides a new way for small molecule detection due to its advantages， such as high recognition characteristics， simple operation and low cost. In this paper， the source， composition， regulatory mechanism， in vivo and in vitro screening of riboswitches， especially the classification of riboswitch biosensors based on small molecular targets were introduced， which aimed to provide a theoretical basis for the development and application of small molecule target riboswitch biosensor.

• Cofactor Strategy and Genome Integration of L‑isoleucine Production by Corynebacterium glutamicum
• Xin JIN, Sumeng WANG, Qingsheng QI, Quanfeng LIANG
• 2022, 12(2):  176-188.  DOI: 10.19586/j.2095-2341.2021.0050
• Abstract ( ) HTML ( ) PDF (1359KB)( )

L?isoleucine which belongs to three branched chain amino acids， is one of the eight essential amino acids for human body. It is widely used in food， medicine， health products， cosmetics and other fields. At present， microbial fermentation is the main method of industrial production for L?isoleucine. Corynebacterium glutamicum is the dominant strain for fermentation production of L?isoleucine. However， random mutation saturates the ability to increase yield， so it is difficult to obtain more high?yield strains. Therefore， rational transformation of mutant strains has become the main way to further improve yield； with the application and optimization of genetic manipulation technology in Corynebacterium glutamicum， metabolic engineering breeding has gradually replaced the traditional mutation breeding. In this paper， the biosynthetic pathway， metabolic regulation mechanism of L?isoleucine in Corynebacterium glutamicum and the strategy of rational transformation of L?isoleucine producing strains were reviewed. The application of cofactor engineering in rational transformation and the strategy of genome integration of Corynebacterium glutamicum were systematically described， aiming to provide a reference basis for the genome integration strategy of L?isoleucine producing strains at the industrial level.

• Research and Application Progress of CRISPR/Cas Technology in Herbicide⁃resistant Crops Breeding
• Yunyan FEI, Jun YANG, Dedao JING, Tianzi LIN, Chuang LI, Huafei QIAN, Shengyuan ZENG, Huaxin HAN, Hongbing GONG
• 2022, 12(2):  189-197.  DOI: 10.19586/j.2095-2341.2021.0170
• Abstract ( ) HTML ( ) PDF (1811KB)( )

CRISPR/Cas system is a simple， inexpensive， high efficiency， and precise tool for genome editing. It can precise genome modification and speed up breeding process， which has great potential in creating novel germplasm. This paper summarized CRISPR/Cas toolkits as well as their application in herbicide-resistant crops breeding， and briefly introduced the current challenges and future application of CRISPR/Cas technology for developing herbicide-resistant crops. The paper aimed to provide a theoretical basis for generating herbicide-resistant crops with CRISPR/Cas system in the future.

• Safety Management of the Crop Produced by New Breeding Techniques
• Yaohui HUANG, Yijie WANG, Litao YANG, Yue JIAO, Zhongwen FU
• 2022, 12(2):  198-204.  DOI: 10.19586/j.2095-2341.2021.0147
• Abstract ( ) HTML ( ) PDF (505KB)( )

New breeding techniques （NBTs） refers to a class of new techniques for molecular breeding based on molecular biology tools， which can produce new powerful traits for crops in a short period and promote the development of new crop varieties， such as gene editing technology， RNA interference （RNAi） technology， cisgenesis technology， etc. These new technologies are currently being widely used in global agricultural breeding， and some new crop varieties have been approved for commercial production. However， the world has not yet reached a consensus on the safety and safety management of new crop varieties produced by new biological breeding technologies， and different safety regulation ideas， which may limit the process of development and commercial application of new crop varieties. At this stage， policies and guiding documents on the safety and supervision of NBTs crops form major developed countries around the world were reviewed in this paper， which was expected provide reference for the safety management and regulation polices of NBTs crops to our country.

• The Tolerance Mechanism of Sunflower Under Abiotic Stress
• Run DU, Siqi ZHANG, Haiwen ZHANG, Tao CHEN
• 2022, 12(2):  205-212.  DOI: 10.19586/j.2095-2341.2021.0154
• Abstract ( ) HTML ( ) PDF (547KB)( )

Sunflower， as one of the five oil crops in China， has high edible value and oil value. Sunflower planting distribution in China concentrated in northeast， northwest and North China， which often faced with drought， saline-alkali， temperature and heavy metal stress problems. This paper mainly summarized the newest progress of several kinds stress in sunflower， and the tolerance mechanism of sunflower in different stress response. By elucidating the tolerance mechanism of sunflower under abiotic stress， the paper was expected to provide theoretical basis and direction for high yield breeding and inverse breeding of sunflower.

• Research Progress on Detection Technology of Meat Adulteration
• Huiru YU, Yi JI, Cheng PENG, Xiaoli XU, Xiaofu WANG, Meihao SUN, Xiaoyun CHEN
• 2022, 12(2):  213-221.  DOI: 10.19586/j.2095-2341.2021.0103
• Abstract ( ) HTML ( ) PDF (564KB)( )

Meat adulteration has seriously threatened public health security. Fast， accurate and reliable animal-derived component detection technology is the key to effective supervision and detection of meat adulteration. This article summarized the common forms of adulteration， and comprehensively summarized and analyzed various methods such as physical， spectroscopy， immunology， and DNA analysis. Especially for the current popular DNA methods， it elaborated four main molecular detection technologies of conventional PCR， real-time fluorescent quantitative PCR， digital PCR and isothermal amplification PCR， and the advantages， disadvantages and applications of these technologies were discussed. This article was expected to point out the future development direction of animal-derived component detection technology.

• Research Progress of Hematopoietic Lymph Gland in Drosophila
• Kun LI, Lihua JIN
• 2022, 12(2):  222-228.  DOI: 10.19586/j.2095-2341.2021.0135
• Abstract ( ) HTML ( ) PDF (860KB)( )

Drosophila melanogaster is one of the important model organisms in biological research. The hemopoietic process of Drosophila mainly occurs during embryonic and larval stages. The lymph gland is the main hematopoietic organ in larval stage， which composed of medullary zone （MZ）， cortical zone （CZ） and posterior signal center （PSC）. A variety of signaling pathways plays a key role in regulating progenitor homeostasis in lymph glands. The relative steady state of blood cell is very important for the hematopoiesis and normal survival of Drosophila. This paper introduced the formation process of lymph gland and the signal pathway of maintaining lymph gland homeostasis， in order to lay a theoretical foundation for the detailed classification of lymph gland blood cells and the corresponding functional research.

• Research Progress on the Treatment of Prion Disease
• Shuxiang LI, Liping AN, Dejuan LIANG, Kaixuan WANG, Jianguo ZHAO
• 2022, 12(2):  229-235.  DOI: 10.19586/j.2095-2341.2021.0156
• Abstract ( ) HTML ( ) PDF (527KB)( )

Prions are infectious proteins formed by normal prion proteins in vivo， and prion diseases are a class of fatal neurodegenerative diseases triggered by prions. At present， although there is no clinical method to treat prion disease， a large number of researchers have studied from many angles and made some progress. This article provided a brief illustration of recent prion disease treatment options related to traditional chemical drugs， gene therapy， immunotherapy and homologous prion proteins， with an emphasis on novel drugs that target intracellular signaling pathways as well as intracellular signaling pathways of mitochondria associated with prion proteins with potential utility. This paper aimed to provide a theoretical basis for the new research direction of prion， in order to promote the clinical application of prion treatment methods.

• Research Progress on Forced Degradation of Biopharmaceuticals
• Xiaoteng ZHANG, Jianjun HAN, Yan BAI
• 2022, 12(2):  236-242.  DOI: 10.19586/j.2095-2341.2021.0171
• Abstract ( ) HTML ( ) PDF (531KB)( )

The forced degradation studies can reveal the possible degradation pathway of medicine， and provide support for the formulation development， storage and transportation of biopharmaceuticals. Therefore， the forced degradation studies paly important roles in biopharmaceuticals research and development， however， there were no standard guidelines on the selection of forced conditions， action time and degradation degree. The commonly used forced degradation conditions （high temperature， pH， oxidation， light， repeated freezing-thawing and shaking or stirring） and the effects of different forced degradation conditions on protein drugs were summarized in this paper， and reasonable design suggestions were put forward， in order to provide reference for the selection of forced degradation studies conditions of biopharmaceuticals.

• Application Progress of Low⁃intensity Pulsed Ultrasound in Osteoarthritis Research
• Chuancai LIANG, Bo QIU
• 2022, 12(2):  243-247.  DOI: 10.19586/j.2095-2341.2021.0080
• Abstract ( ) HTML ( ) PDF (445KB)( )

Osteoarthritis （OA） is a degenerative joint disease， which characterized by cartilage degeneration， osteosclerosis and chronic synovial inflammation. Arthroplasty is currently the only effective treatment for end-stage OA， but its prognosis is poor and the life span of the artificial joint is limited. Therefore， the focus of OA research has shifted to disease prevention and early treatment. Low-intensity pulsed ultrasound （LIPUS） not only promotes fracture healing and regeneration， but also shows beneficial effects in soft tissue repair， regeneration and anti-inflammation. Studies have shown that the potential role of LIPUS in soft tissue regeneration. This article briefly introduced the therapeutic mechanism of LIPUS and its connection with the pathogenesis of OA， and summarized the current progress of basic and clinical research on the use of LIPUS to prevent the occurrence and development of OA and to promote the regeneration of articular cartilage tissue， in order to provide a theoretical basis for LIPUS as a potential treatment for articular cartilage degeneration prevention in the future.

Articles

• Establishment of Qualitative PCR Detection of Transgenic Insect⁃resistant Maize CM8101
• Hongtao WEN, Yang YANG, Yijia DING, Ran YUAN, Ruiying ZHANG, Zhiyuan XU, Jingang LIANG
• 2022, 12(2):  248-255.  DOI: 10.19586/j.2095-2341.2021.0158
• Abstract ( ) HTML ( ) PDF (4137KB)( )

Transgenic insect-resistant maize CM8101 is a new strain with modified Bt gene Cry1Ab?Ma syntheszied by artificial transformation. It is developed by China and has better insect resistance. At present， this strain has entered the stage of productive test， and it has important industrial application prospect in China. According to the 5′ flanking sequence information of transgenic maize CM8101， the optimal specific primer and probe combinations were designed and screened. A normal PCR assay and a real-time PCR assay for transgenic insect-resistant maize CM8101 were developed in this paper. Both methods could be used to qualitatively detect the component of transgenic insect-resistant maize CM8101 with good specificity. The results showed that the detection limit of normal PCR method was up to 0.1%， and the detection limit of real-time PCR method was up to 0.05%. Establishment of the two qualitative PCR methods provides new reference method for accurate and efficient detection of transgenic insect resistant maize CM8101 and its products in the future.

• Cloning and Functional Studies of Nitrate Transporter Gene GeNRT2.1 in Glossostigma elatinoides
• Jiu HUANG, Shuangfeng SHI, Erte ZHANG, Mei LI, Yue YU, Yuhui LIU
• 2022, 12(2):  256-264.  DOI: 10.19586/j.2095-2341.2021.0033
• Abstract ( ) HTML ( ) PDF (2242KB)( )

Nitrate transporter （NRT） is a key protein for plants to recognize， absorb and transport nitrate， which plays an important role in promoting crop root development and crop yield improving. In this study， through the screening of aquatic plants， we used Glossostigma elatinoides as materials， designed degenerate primers based on the conserved regions of NRT proteins in different species， used PCR and RACE technology to clone GeNRT2.1 gene for the first time. Evolutionary analysis results showed that GeNRT2.1 was most closely related to Nicotiana tabacumNRT2.1 in evolutionary relationship. qRT-PCR results showed that the expression of GeNRT2.1 in roots was the highest， followed by leaves and stems. In addition， the expression of GeNRT2.1 in roots， leaves， and stems of low concentration nitrate （0.5 mmol·L^-1） were 1.89， 1.93 and 2.07 times than that of high concentration nitrate （2 mmol·L^-1）. Functional complementation experiments results showed that GeNRT2.1 could restore the growth of defective yeast Δynr， and has the function of nitrate transporter. By enriching NRT genetic resources， this study hopes to provide a theoretical basis for cultivating genetically modified crops with high-efficiency utilization of nitrogen fertilizer， developing green agriculture， and ensuring food security and environmental safety in our country.

• Study on Feeding Effect of Silage Containing Forsythia on Meat Goose
• Qi AN, Yabin CAO, Yanbo NIU, Tao YUAN
• 2022, 12(2):  265-269.  DOI: 10.19586/j.2095-2341.2021.0107
• Abstract ( ) HTML ( ) PDF (482KB)( )

The study aimed to research the effect of silage containing forsythia on the growth， morbidity and survival rate of meat geese and improve the overall health of the geese. The suspensions of Lactobacillus plantarum and Aspergillus usamil were prepared and added to the silage containing forsythia in proportion. After natural fermentation for 60 days， the products were used for the feeding experiment of geese. The 28-day-old meat geese were randomly divided into three groups and fed with silage with different forsythia content for 42 days. During the feeding process， the production performance of silage containing forsythia of each group were observed. The results showed that the functional ingredients content of forsythin and forsythin A in the silage containing 5% and 10% forsythia branches were statistically significant difference （P<0.05）. The survival rate of the silage containing forsythia increased by 4.38%~4.63% and the daily gain increased by 3.07%~4.33% and the feed to meat ratio reduced significantly （P<0.05）. The palatability of the branches of forsythia was improved effectively by fermenting of Lactobacillus plantarum and Aspergillus usamil andthe health of the geese improved after feeding.The application research of using discarded medicinal materials as feed additives provided new ideas for reducing production costs， preventing and treating poultry diseases.

• Study on Uridine Diphosphate Sugar Synthesis by Immobilized Enzyme
• Haichao LYU, Zhekang JIA, Wen ZHANG, Liwen JIANG, Yuwen CHAO, Wenfang DOU
• 2022, 12(2):  270-280.  DOI: 10.19586/j.2095-2341.2021.0146
• Abstract ( ) HTML ( ) PDF (3460KB)( )

Using biological enzymes to synthesize more kinds of uridine diphosphate sugars（UDP sugars）， the reuse rate of biological enzymes is low. In order to synthesize more kinds of UDP sugars with high effciency， N-acetylhexosamine kinase （NahK） and uridine transferase （GlmU） with HIS tag were immobilized on nickel chelated polyacrylate resin. Using immobilized NahK and immobilized GlmU as catalytic enzymes and different monosaccharides as substrates， the one pot method synthesis of uridine diphosphate sugar was studied. The product was purified by Q sepharose. The reaction products were detected by high performance liquid chromatography、mass spectrometry and ¹H nuclear magnetic resonance. It was confirmed that the actual loading of nickel chelated polyacrylate resin on free NahK and GlmU were 10 and 20 mg·g^-1， respectively. The optimal ratio of immobilized enzyme was 5.5 g immobilized NahK and 2.5 g immobilized GlmU. The optimal pH and temperature of immobilized enzyme were 8.0 and 35 ℃， respectively. The total immobilized enzyme could stably react for 5 batches in repeated reaction. Glucose， N-acetylglucosamine and mannose could participate in the one pot method reaction. The relative molecular weights of UDP sugars were 566、607 and 566， respectively. In this system， glucuronic acid， galactose and fructose could not synthesize the corresponding UDP sugars. Based on immobilized enzyme technology， UDP glucose， UDP N-acetylglucosamine and UDP mannose were synthesized in one pot method.

• Method Establishment and Performance Evaluation of Detecting Concentration of Serum Amyloid A Based on Bare Magnetic Particles Bead System
• Xinxin GAO, Mengnan MA, Chunlong LIU, Mengfan WANG
• 2022, 12(2):  281-287.  DOI: 10.19586/j.2095-2341.2021.0095
• Abstract ( ) HTML ( ) PDF (1177KB)( )

Biotin interference， low luminescence yield and poor specificity are the main problems of traditional streptavidin-magnetic particles and enzymatic luminescence systems. In this study， based on the sandwich principle of antibody-antigen-antibody， a bare magnetic particles-acridinyl ester luminescence system was established for the rapid determination of serum amyloid A（SAA） by using bare magnetic particles as carriers to conjunct SAA antibodies and acridinium ester as luminescent marker. The detection performance of the method （including： blank limit， detection limit， linear range， precision verification， interference test， Hook effect， methodological comparison， etc.） was evaluated. The results showed that the SAA antibody was successfully coupled to the bare magnetic particles. The blank limit of this method was 0.6 mg·mL^-1， and the detection limit was 1.0 mg·mL^-1 with the linear range of 1~100 mg·mL^-1 （R²>0.990）. The repeatability and within-laboratory precision expressed by CV were both <10%. The interference test of hemoglobin， bilirubin， and triglycerides in clinical samples were all <10%. Bland-Altman analysis indicated that the difference fluctuated within the consistency limit of 95% CI between the established method and the commercial Siemens reagent and showed a good correlation （R²=0.987）. The results of this study indicated that the established bare magnetic particles-acridinyl ester luminescence detection system is promising for the rapid detection of SAA in serum.

• Analysis of Genetic Polymorphisms at 37 Y⁃STR Loci in Dezhou Han Population
• Longfei MIAO, Dapeng SUN, Wenhua MA, Jianjun ZHONG
• 2022, 12(2):  288-295.  DOI: 10.19586/j.2095-2341.2021.0148
• Abstract ( ) HTML ( ) PDF (687KB)( )

To investigate the genetic polymorphism of 37 Y-STR loci in 598 unrelated male individuals of Dezhou Han population，and to explore its application value in forensic medicine and population genetics. The 37 Y-STR loci were amplified by AGCU Y37 kit， and the amplification products were analyzed through 3500xL genetic analyzer. The phylogenetic tree of Dezhou Han population and other 15 reference populations was constructed by Neighbor Joining （NJ） with MEGA 7.0 software to explore the genetic relationship. The results showed that 593 different haplotypes were observed in 598 unrelated male individuals. The genetic diversity （GD） ranged from 0.113 9（DYS645） to 0.971 4（DYS385a/b）. The haplotype diversity（HD） and discriminative capacity（DC） were 0.999 971 989 and 0.991 6， respectively， which showed that the 37 Y-STR loci were highly polymorphic in Dezhou Han population. The results of genetic distance， multidimensional scaling （MDS） and phylogenetic tree indicated that the genetic distance between Dezhou Han population and other Han populations was close in population genetic analysis， and the genetic characteristics of different populations were consistent with language family， historical formation and geographical distribution. The results obtained in this study can provide basic data support for forensic science and population genetics research of Dezhou Han population.

• Screening of Triple⁃negative Breast Cancer⁃associated miRNAs and Bioinfor⁃matics Analysis of the Target Genes
• Xin HU, Huici MA, Mingsheng HAN, Xiaohong YUAN, Mingyu YANG, Yanqin MA
• 2022, 12(2):  296-304.  DOI: 10.19586/j.2095-2341.2021.0178
• Abstract ( ) HTML ( ) PDF (6655KB)( )

Bioinformatics methods were used to screen and analyze triple-negative breast cancer （TNBC） associated miRNAs and their target genes which could serve as potential molecular targets in the study of TNBC. GEO2R was used to analyze the miRNA chip datasets and screen the five upregulated and five downregulated miRNAs with the highest fold changes. miRWalk， TargetScan and miRDB predicted target genes and performed Veen analysis to obtain the overlap. We used DAVID to perform GO enrichment analysis and KEGG pathway analysis of target genes. The STRING database was used to construct a protein-protein interaction network， and combined with Cytoscape to construct a miRNA-target gene regulatory network， so as to screen out the key miRNAs and their key target genes. The survival of target genes was analyzed by GEPIA2 database. 486 differentially expressed miRNAs were screened by GEO2R， among them the upregulated and downregulated miRNAs were 298 and 188 respectively. Enrichment analysis of the five up-regulated and five down-regulated miRNA target genes with the largest fold difference showed that the target genes were mainly involved in the ErbB signaling pathway， the transcriptional regulation disorder in cancer， and the cGMP-PKG signaling pathway and so on. miRNA-target gene regulatory network showed that the key upregulated miRNA was miR-611 and its key target genes were CDC27， UBE2D2， UBR1， SPSB1， HERC2 and RLIM. The key downregulated miRNA was miR-1205 and its key target genes were WSB1， FBXL8， UBE2W， PTPN11， ARF6， DNAJC6 and COPS2. Survival analysis showed that the upregulated expression of UBR1 （P=0.007 2） and PTPN11 （P=0.029） could significantly decrease the overall survival rate of TNBC patients. The key miRNAs and their target genes obtained in the study can be used as potential candidate targets for early diagnosis， precising therapy and prognosis judgment of TNBC， and can provide guidance for further research.

• Study on the Effect of Allicin on Rat Kidney Stone Formation by Inhibiting OPN Expression and Activation of NF‑κB Pathway
• Xuhong XU, Jianming SUN, Lunzhong ZHANG, Liangyu XU, Xiangyang ZENG, Longfei SUN, Xiaofeng CHEN
• 2022, 12(2):  305-312.  DOI: 10.19586/j.2095-2341.2021.0106
• Abstract ( ) HTML ( ) PDF (2839KB)( )

Allicin can improve the injury of renal tubular epithelial cells induced by oxalic acid， this study took rats with kidney stones as the research object to explore the effect of allicin on rats with kidney stones and its possible mechanism. 1% ethylene glycol+2% ammonium chloride method to prepare a model of rats with kidney stones （except blank group）. Allicin 7.5 mg·kg^-1 （low allicin dose group）， 15 mg·kg^-1 （high allicin dose group）， potassium sodium hydrogen citrate 0.6 g·kg^-1 （positive control group）， and 0.9% sodium chloride solution for other groups （blank group） were gavaged respectively. The indexes related to kidney stone disease in each group were detected. Compared with the blank group， the model group had significantly higher renal index， Cr， BUN levels， aspartate aminotransferase （AST）， alanine aminotransferase （ALT） activity， 24 h urine output， urine oxalic acid， calcium and phosphorus content （P<0.05）， and the calcium oxalate crystallization score was significantly increased （P<0.05）， magnesium content was significantly decreased （P<0.05）， osteopontin （OPN） expression was significantly increased （P<0.05）， nuclear factor?κB（NF?κB） pathway was activated. Compared with the model group， the renal index， Cr， BUN levels and AST， ALT activity， 24 h urine output， urine oxalic acid， calcium and phosphorus content in the low allicin dose group， high dose group and the positive control group were significantly reduced （P<0.05）， and calcium oxalate crystal score was significantly reduced （P<0.05）， the magnesium content was significantly increased （P<0.05）， OPN expression was significantly reduced （P<0.05）， and the NF?κB pathway was inhibited. Allicin can inhibit the formation of kidney stones by improving the renal function indexes of rats， inhibiting the expression of osteopontin and the activation of NF?κB pathway.

• Construction and Expression of Recombinant Vectors of Staphylococcal Enterotoxins A, B, C, D and E
• Weifeng CHEN, Liwei CUI, Weidan CHANG, Longjiao ZHU, Wentao XU
• 2022, 12(2):  313-317.  DOI: 10.19586/j.2095-2341.2021.0136
• Abstract ( ) HTML ( ) PDF (1109KB)( )

As one of the main factors causing bacterial food poisoning and gastroenteritis， Staphylococcal enterotoxins （SEs） is a group of soluble small-molecule proteins with similar structural toxicity and different serotypes with the average molecular mass of 26~30 kD. To prepare pure products of SEs， the gene sequence of SEA， SEB， SEC， SED and SEE were synthesized， then the proraryotic expression vectors of five enterotoxins were constructed and transferred into BL21（DE3） cells for expression. SDS-PAGE and Western blot showed that the five enterotoxin proteins were successfully expressed， and a amount of soluble proteins could be obtained at a lower induction temperature （16 ℃）. In this study， five soluble proteins of Staphylococcal enterotoxin were successfully prepared， which laid a foundation for better solving the food safety problems caused by SEs in the future.