Entity

Time filter

Source Type


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.


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.


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.


Wang B.,Tianjin University of Science and Technology | Gao Q.,Tianjin University of Science and Technology | Gao Q.,Key Laboratory of Industrial Microbiology | Liu B.,Tianjin University of Science and Technology | And 3 more authors.
ICBBT 2010 - 2010 International Conference on Bioinformatics and Biomedical Technology | Year: 2010

Bacillus coagulans TL-4 strain is a thermophilic bacterium for high L-lactate production. We reported here that its 779-bp partial NAD +-dependent L-lactate dehydrogenase (LDH) gene sequence (GenBank accession no. GU354320) encoding a deduced 259 amino acid peptide was cloned by using one pair of designed degenerate primers. The amino acid sequence alignment and the built phylogenetic tree revealed that this partial LDH of B. coagulans TL-4 shared high homology with the conserved LDH stretches from 59.17% to 74.70% among other 10 Bacillus species and 48.81% to that of Lactobacillus sp. MD-1. Furthermore, three highly conservative LDH regions, one (Val1∼ Asp34) for NADH binding site and two (Asp59∼Ile 86 and Asn107∼Arg139) for the distinct active sites, were also found in this NAD+-dependent LDH stretch. © 2010 IEEE.


Chen Y.-P.,Tianjin University of Science and Technology | Gao Q.,Tianjin University of Science and Technology | Gao Q.,Key Laboratory of Industrial Microbiology | Qiao N.-N.,Tianjin University of Science and Technology | And 3 more authors.
Proceedings of the 2010 2nd International Conference on Future Computer and Communication, ICFCC 2010 | Year: 2010

Lipase activity is popular in staphylococci. We described here that a 781-bp consensus lipase gene sequence of Staphylococcus caprae TCCC 11546, which encoded a deduced polypeptide of 260 amino acid residues, was cloned using the degenerate primers. The amino acid sequence alignment and the phylogenetic tree revealed that this 260-amino acid partial lipase of S. caprae was highly homologous from 55.0% to 98.8% among other 11 conserved lipase stretches from other 11 Staphylococcus species. Moreover, two amino acid residues, Ser39 and Asp230, were identified in the putative lipase catalytic triad, the consensus 'P-loop' motif (-[AG]-x4-G-K-[ST]-) was also found in this partial lipase stretch. ©2010 IEEE.

Discover hidden collaborations