http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Xuejun, Cao,Jianhang, Zhu,Dongzhi, Wei,Hur, Byong Ki 한국공업화학회 2002 Journal of Industrial and Engineering Chemistry Vol.8 No.3
Partition behavior of cephalexin and 7-ADCA in PEG-salts and EOPO-salts aqueous two-phase systems has been investigated under various different conditions. Effect of polymer molecular weight, salts types, tie line length on partition coefficients of cephalexin and 7-ADCA were described. Additives such as salts, water miscible solvents and surfactants were used to improve partition of cephalexin and 7-ADCA. NaSCN shows greatest influence on partition of cephalexin and 7-ADCA in 20% PEG 400-17.5% (NH_4)_2SO_4. Cephalexin and 7-ADCA partition coefficients reached 12.92 and 2.58, respectively. While NaCI shows greatest influence on partition of cephalexin and 7-ADCA in E0_40PO_60-(NH_4)_2SO_4. In 15% E0_40P0_60-13% (NH_4)_2SO_4 ATPS, partition coefficients of cephalexin and 7-ADCA reached 0.08 and 0.42, respectively. Cephalexin and 7-ADCA shows different partition trend in PEG-(NH_4)_2SO_4 and EOPO-(NH_4)_2SO_4 ATPS. In EOPO-(NH_4)_2SO_4 ATPS, diagrams of PEG3000-(NH_4)_2SO_4, E0_40PO_60-(NH_4)_2SO_4, E0_20PO_80-(NH_4)_2SO_4 were prepared and their differences were analyzed, and recovery of E0_40PO_60-(NH_4)_2SO_4 ATPS was performed with yield of 90-95%.
Jianbing Yang,Kefeng Ni,Dongzhi Wei,Yuhong Ren 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.5
Ni2+-functionalized Fe3O4@polydopamine magnetic nanoparticles (Ni2+-PD-MNPs) were designed and synthesized by in situ coating of magnetic nanoparticles with polydopamine, followed by conjugation of Ni2+ to the polydopamine film. The Ni2+-PD-MNPs were used to purify His-tagged red fluorescent protein (His-RFP) via affinity interaction between Ni2+ and the His-tag. The results showed that the Ni2+-PD-MNPs had extraordinary selectivity for His-RFP purification. In addition, a Histagged transaminase (ω-transaminase BJ110) was selectively immobilized onto the Ni2+-PD-MNPs without purification, and the immobilized enzyme showed improved specific activity, as well as enhanced stability and reusability.
Ma Xingyuan,Zheng Wenyun,Wang Tianwen,Wei Dongzhi,Ma Yushu The Microbiological Society of Korea 2006 The journal of microbiology Vol.44 No.3
The Escherichia coli heat-labile enterotoxin B subunit (HLT-B) is one of the most powerful mucosal immunogens and known mucosal adjuvants. However, the induction of high levels of HLT-B expression in E. coli has proven a difficult proposition. Therefore, in this study, the HLT-B gene was cloned from pathogenic E. coli and expressed as a fusion protein with GST (glutathion S-transferase) in E. coli BL2l (DE3), in an attempt to harvest a large quantity of soluble HLT-B. The culture conditions, including the culture media used, temperature, pH and the presence of lactose as an inducer, were all optimized in order to obtain an increase in the expression of soluble GST-rHLT-B. The biological activity of the purified rHLT-B was assayed in a series of GMI-ELISA experiments. The findings of these trials indicated that the yield of soluble recombinant GST-rHLT-B could be increased by up to 3-fold, as compared with that seen prior to the optimization, and that lactose was a more efficient alternative inducer than IPTG. The production of rHLT-B, at 92 % purity, reached an optimal level of 96 mg/l in a 3.7 L fermentor. The specific GM1 binding ability of the purified rHLT-B was determined to be almost identical to that of standard CTB.
Xingyuan Ma,Wenyun Zheng,Tianwen Wang,Dongzhi Wei 한국미생물학회 2006 The journal of microbiology Vol.44 No.3
The Escherichia coli heat-labile enterotoxin B subunit (HLT-B) is one of the most powerful mucosal immunogens and known mucosal adjuvants. However, the induction of high levels of HLT-B expression in E. coli has proven a difficult proposition. Therefore, in this study, the HLT-B gene was cloned from pathogenic E. coli and expressed as a fusion protein with GST (glutathion S-transferase) in E. coli BL21 (DE3), in an attempt to harvest a large quantity of soluble HLT-B. The culture conditions, including the culture media used, temperature, pH and the presence of lactose as an inducer, were all optimized in order to obtain an increase in the expression of soluble GST-rHLT-B. The biological activity of the purified rHLT-B was assayed in a series of GM1-ELISA experiments. The findings of these trials indicated that the yield of soluble recombinant GST-rHLT-B could be increased by up to 3-fold, as compared with that seen prior to the optimization, and that lactose was a more efficient alternative inducer than IPTG. The production of rHLT-B, at 92% purity, reached an optimal level of 96 mg/l in a 3.7 L fermentor. The specific GM1 binding ability of the purified rHLT-B was determined to be almost identical to that of standard CTB.
( Yuguo Dong ),( Jian Zhang ),( Rui Xu ),( Xinxin Lv ),( Lihua Wang ),( Aiyou Sun ),( Dongzhi Wei ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.11
Mycophenolic acid (MPA) is an antibiotic produced by Penicillium brevicompactum. MPA has antifungal, antineoplastic, and immunosuppressive functions, among others. β-Hydroxy-β-methylglutaryl-CoA (HMG-CoA) lyase is a key enzyme in the bypass metabolic pathway. The inhibitory activity of HMG-CoA lyase increases the MPA biosynthetic flux by reducing the generation of by-products. In this study, we cloned the P. brevicompactum HMG-CoA lyase gene using the thermal asymmetric interlaced polymerase chain reaction and gene walking technology. Agrobacterium tumefaciens-mediated transformation (ATMT) was used to insert a mutated HMG-CoA lyase gene into P. brevicompactum. Successful insertion of the HMG-CoA lyase gene was confirmed by hygromycin screening, PCR, Southern blot analysis, and enzyme content assay. The maximum MPA production by transformants was 2.94 g/l. This was 71% higher than wild-type ATCC 16024. Our results demonstrate that ATMT may be an alternative practical genetic tool for directional transformation of P. brevicompactum.
( Yanchen Yin ),( Youzhi Mao ),( Xiaolie Yin ),( Bei Gao ),( Dongzhi Wei ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.7
The filamentous fungus Aspergillus oryzae is a well-known expression host used to expresshomologous and heterologous proteins in a number of industrial applications. To facilitate higher yields of proteins of interest, we constructed the pAsOP vector to express heterologous proteins in A. oryzae. pAsOP carries a selectable marker, pyrG, derived from Aspergillus nidulans, and a strong promoter and a terminator of the amyB gene derived from A. oryzae. pAsOP transformed A. oryzae efficiently via the PEG-CaCl2-mediated transformation method.As proof of concept, green fluorescent protein (GFP) was successfully expressed in A. oryzae transformed by pAsOP-GFP. Additionally, we identified a novel fungal α-amylase (PcAmy) gene from Penicillium sp. and cloned the gene into the vector. After transformation by pAsOPPcAmy, the α-amylase PcAmy from Penicillium sp. was successfully expressed in a heterologous host system for the first time. The α-amylase activity in the A. oryzae transformant was increased by 62.3% compared with the untransformed A. oryzae control. ThePcAmy protein produced in the system had an optimum pH of 5.0 and optimum temperature of 30oC. As a cold-adapted enzyme, PcAmy shows potential value in industrial applications because of its high catalytic activity at low temperature. Furthermore, the expression vector reported in this study provides promising utility for further scientific research and biotechnological applications.