Key Laboratory of Industrial Microbiology

Tianjin, China

Key Laboratory of Industrial Microbiology

Tianjin, China
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Luo X.-G.,Key Laboratory of Industrial Microbiology | Luo X.-G.,Tianjin University of Science and Technology | Tian W.-J.,Key Laboratory of Industrial Microbiology | Tian W.-J.,Tianjin University of Science and Technology | And 7 more authors.
Pharmaceutical Biology | Year: 2011

Context: The kringle 2 plus serine protease domains (K2S) of human tissue plasminogen activator (tPA) is an efficacious thrombolytic drug, which has been used to treat heart attacks and strokes by breaking up the clots that cause them. It has nine disulfide bridges, which are needed for proper folding and be the bottleneck in improving the production in the Escherichia coli system. So far, few reports have described the production of soluble active K2S from E. coli. Objective: To achieve high-level expression of active K2S in the E. coli system. Materials and methods: The DNA fragment coding for K2S was fused with the E. coli disulfide isomerase DsbC. The constructed fusion protein was expressed in E. coli, and then purified with the Ni2+-chelating affinity chromatography. K2S was released by cleavage with Factor Xa protease, and the thrombolytic activity was determined using the fibrin plate assay. Results: The fusion protein DsbC-K2S was found in the culture supernatant of recombinant E. coli as a soluble form of ∼40%. The result of fibrinolysis fibrin plate assay showed that the purified recombinant K2S exhibited significant fibrinolysis activity in vitro. Discussion and conclusion: These works provided a novel approach for the production of active K2S in E. coli without the requirements of in vitro refolding process, and might establish a significant foundation for the following production of K2S. © 2011 Informa Healthcare USA, Inc.


Tian H.,Key Laboratory of Industrial Microbiology | Luo X.-G.,Key Laboratory of Industrial Microbiology | Luo X.-G.,Tianjin University of Science and Technology | Han Z.,Key Laboratory of Industrial Microbiology | And 5 more authors.
Advances in Intelligent and Soft Computing | Year: 2012

Lactobacillus plantarum (L. plantarum) is a flexible and versatile microorganism that inhabits a variety of environmental niches, and some strains are marketed as probiotics. In this study, a strainTH1 which was isolated from silage in our former works was classified asL. plantarum by 16S rDNA sequence analysis and phylogenetic tree. Then its potential abilities of bile tolerance, nitrate reduction and anti-hypertension were investigated. The results showed that L. plantarum TH1 had capacity to resistance to bile salt, directly deoxygenate nitrate to nitrogen or ammonia rather then nitrite, and produce ACE inhibitory components in fermented milk. These works indicated that this novel lactobacillus strain might be considered as candidates for probiotics strains using in the food or drug system to improve the health of patients suffering from hypertension or other chronic disease. © 2012 Springer-Verlag GmbH.


Man S.,Tianjin University | Qiu P.,Key Laboratory of Industrial Microbiology | Li J.,Key Laboratory of Industrial Microbiology | Zhang L.,Key Laboratory of Industrial Microbiology | Gao W.,China Pharmaceutical University
Environmental Toxicology | Year: 2015

Rhizoma Paridis saponins (RPS) is a traditional Chinese medicine (TCM) from the plant Paris polyphylla var. yunnanensis (Fr.) Hand.-Mazz. Despite its potentially clinical utility such as anticancer and anti-inflammation, it has slight side effects and toxicity as previous report. In this work, 90-day administration of RPS induced liver injury. 1H-NMR- and GC/MS-based metabonomic analyses in conjunction with histopathological examinations, blood biochemistry and hepatic phase I and II enzymes assays were performed to evaluate the toxic mechanisms of RPS induced in rats. As a result, oral administration of RPS possessed certain liver toxicity in SD rats. 1H-NMR and GC/MS data indicated that RPS inhibited the oxidation of fatty acids, glycolysis, and TCA cycle pathway, and disturbed glycine, serine, and threonine metabolism. Low expression of TG, T-CHO, and LDL-C and high levels of ALT and AST indicated that chronic exposure to RPS caused hepatocyte damage, synthesis dysfunction, and transportation failure of lipoproteins. In addition, RPS downregulated the mRNA levels of CYP1A2, CYP2E1, and UGTs. In conclusion, we used metabonomics approach to study the toxicity of RPS for the first time. This research demonstrated that metabonomics method was a promising tool to study and diagnose TCM-induced toxicity. © 2015 Wiley Periodicals, Inc.


Liao X.-H.,Key Laboratory of Industrial Microbiology | Liao X.-H.,Tianjin University of Science and Technology | Wang N.,Key Laboratory of Industrial Microbiology | Wang N.,Tianjin University of Science and Technology | And 10 more authors.
IUBMB Life | Year: 2011

Myocardin is a remarkably potent transcriptional coactivator expressed specifically in cardiac muscle lineages and smooth muscle cells during postnatal development. Myocardin shares homology with myocardin-related transcription factor-A (MRTF-A), which are expressed in a broad range of embryonic and adult tissues. Our previous results show that myocardin induces cardiac hypertrophy. However, the effects of MRTF-A in cardiac hypertrophy remain poorly understood. Our present work further demonstrates that myocardin plays an important role in inducing hypertrophy. At the same time, we find that overexpression of MRTF-A in neonatal rat cardiomyocytes might induce cardiomyocyte hypertrophy. Furthermore, MRTF-A expression is induced in phenylephrine, angiotensin-II, and transforming growth factor-β-stimulated cardiac hypertrophy, whereas a dominant-negative form of MRTF-A or MRTF-A siRNA strongly inhibited upregulation of hypertrophy genes in response to hypertrophic agonists in neonatal rat cardiomyocytes. Our studies indicate that besides myocardin, MRTF-A might play an important role in cardiac hypertrophy. Our findings provide novel evidence for the future studies to explore the roles of MRTFs in cardiac hypertrophy. © 2011 IUBMB.


Shen Y.,Key Laboratory of Industrial Microbiology | Shen Y.,Tianjin University of Science and Technology | Ma B.,Key Laboratory of Industrial Microbiology | Ma B.,Tianjin University of Science and Technology | And 8 more authors.
Proceedings - 2010 3rd International Conference on Biomedical Engineering and Informatics, BMEI 2010 | Year: 2010

In this paper, the biotransformation of 17α-hydroxypregna-4-ene-3,20- dione-21-acetate (RSA) and 17α-hydroxypregna-4-ene-3,20-dione (RS) by Absidia coerulea AC307 was selected as a model system for evaluating the mechanism of β-cyclodextrin (β-CD) on the the steroid 11β-hydroxylation biotransformation process. It was found that the addition of cyclodextrin to RS and RSA biotransformation systems could effectively increase the speed of biotransformation and decrease the reactant's absorption by microorganism. There may be some relation between the two kinds affection induced by cyclodextrin, and the idea can be validated by Shewmon P G's theory. It showed that cyclodextrin can affect the steroid-permeating capability of the microorganism, and that seemed to be favourable for reactant entered into the microorganism. ©2010 IEEE.


PubMed | Key Laboratory of Industrial Microbiology
Type: Journal Article | Journal: Pharmaceutical biology | Year: 2011

The kringle 2 plus serine protease domains (K2S) of human tissue plasminogen activator (tPA) is an efficacious thrombolytic drug, which has been used to treat heart attacks and strokes by breaking up the clots that cause them. It has nine disulfide bridges, which are needed for proper folding and be the bottleneck in improving the production in the Escherichia coli system. So far, few reports have described the production of soluble active K2S from E. coli.To achieve high-level expression of active K2S in the E. coli system.The DNA fragment coding for K2S was fused with the E. coli disulfide isomerase DsbC. The constructed fusion protein was expressed in E. coli, and then purified with the Ni(2+)-chelating affinity chromatography. K2S was released by cleavage with Factor Xa protease, and the thrombolytic activity was determined using the fibrin plate assay.The fusion protein DsbC-K2S was found in the culture supernatant of recombinant E. coli as a soluble form of ~40%. The result of fibrinolysis fibrin plate assay showed that the purified recombinant K2S exhibited significant fibrinolysis activity in vitro.These works provided a novel approach for the production of active K2S in E. coli without the requirements of in vitro refolding process, and might establish a significant foundation for the following production of K2S.


PubMed | Key Laboratory of Industrial Microbiology
Type: Journal Article | Journal: Current microbiology | Year: 2010

Plectasin is a defensin-like antimicrobial peptide isolated from a fungus, the saprophytic ascomycete Pseudoplectania nigrella. Plectasin showed marked antibacterial activity in vitro against Gram-positive bacteria, especially Streptococcus pneumoniae, including strains resistant to conventional antibiotics. Plectasin could kill the sensitive strain as efficaciously as vancomycin and penicillin and without cytotoxic effects on mammalian cell viability. In order to establish a bacterium-based plectasin production system, in the present study, the coding sequence of plectasin was optimized, and then cloned into pET32a (+) vector and expressed as a thioredoxin (Trx) fusion protein in Escherichia coli. The soluble fusion protein collected from the supernatant of the cell lysate was separated by Ni(2+)-chelating affinity chromatography. The purified protein was then cleaved by Factor Xa protease to release mature plectasin. Final purification was achieved by Ni(2+)-chelating chromatography again. The recombinant plectasin exhibited the same antimicrobial activity as reported previously. This is the first study to describe the expression of plectasin in E. coli expression system, and these works might provide a significant foundation for the following production or study of plectasin, and contribute to the development and evolution of novel antimicrobial drugs in clinical applications.


Wu F.,Tianjin University of Science and Technology | Xie X.,Tianjin University of Science and Technology | Shi J.,Tianjin University of Science and Technology | Xu Q.,Tianjin University of Science and Technology | Chen N.,Key Laboratory of Industrial Microbiology
2010 4th International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2010 | Year: 2010

Inosine monophosphate dehydrogenase(IMPDH, Ec1.1.1.205) is the rate-limiting enzyme for de nove guanosine monophosphate synthesis. The IMPDH encoding gene guaB has been clonded and sequenced from Bacillus amyloliquefaciens GR600, a overproduction-guanosine strain. A fragment contained the stuctrural gene guaB encoding IMPDH from GR600 was constructed into expression vector pET-His. The recombinant expression plamid was transformed into Escherichia coil strain BL21(DE3), induced by IPTG and expressed. The recombinat IMPDH was purified by Ni-NTA resins. The result of SDS-PAGE showed that molecular weight of the recombinat IMPDH was 54 kD. Enzyme activity assay showned that the optimum pH value and temperatrure of the recombinat IMPDH were 8.0 and 40 °C. The results have great significance in genetical modify of producing strain. ©2010 IEEE.


PubMed | Key Laboratory of Industrial Microbiology
Type: Journal Article | Journal: IUBMB life | Year: 2011

Myocardin is a remarkably potent transcriptional coactivator expressed specifically in cardiac muscle lineages and smooth muscle cells during postnatal development. Myocardin shares homology with myocardin-related transcription factor-A (MRTF-A), which are expressed in a broad range of embryonic and adult tissues. Our previous results show that myocardin induces cardiac hypertrophy. However, the effects of MRTF-A in cardiac hypertrophy remain poorly understood. Our present work further demonstrates that myocardin plays an important role in inducing hypertrophy. At the same time, we find that overexpression of MRTF-A in neonatal rat cardiomyocytes might induce cardiomyocyte hypertrophy. Furthermore, MRTF-A expression is induced in phenylephrine, angiotensin-II, and transforming growth factor--stimulated cardiac hypertrophy, whereas a dominant-negative form of MRTF-A or MRTF-A siRNA strongly inhibited upregulation of hypertrophy genes in response to hypertrophic agonists in neonatal rat cardiomyocytes. Our studies indicate that besides myocardin, MRTF-A might play an important role in cardiac hypertrophy. Our findings provide novel evidence for the future studies to explore the roles of MRTFs in cardiac hypertrophy.


PubMed | Key Laboratory of Industrial Microbiology
Type: Journal Article | Journal: Biotechnology letters | Year: 2010

Alpha-amylases are important industrial enzymes with a wide range of applications. Although medium-temperature alpha amylase (AmyE) has some practical advantages, its low yield has limited its applications. When an amyE gene from Bacillus subtilis BF768 was cloned into vector pWB980 and over-expressed in B. subtilis WB600, high activities (723 U ml(-1)) of secreted AmyE were produced. Recombinant AmyE was purified to a specific activity of 36 U mg(-1) having optimal activity at pH 6.0 and 60 degrees C.

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