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Chang, Ziwei,Lu, Ming,Ma, Yunqi,Kwag, Dong-Geon,Kim, Seo-Hyun,Park, Ji-Min,Nam, Bo-Hye,Kim, Young-Ok,An, Cheul-Min,Li, Huayue,Jung, Jee H,Park, Jang-Su Springer-Verlag ; Springer 2015 Amino acids Vol.47 No.3
<P>Recombinant expression in Escherichia coli allows the simple, economical, and effective production of bioactive peptides. On the other hand, the production of native peptides, particularly those rich in disulfide bonds, is a major problem. Previous studies have reported that the use of carrier proteins for fusion expression can result in good peptide yields, but few are folded correctly. In this study, two transmembrane small proteins in E. coli, YoaJ and YkgR, which both orientate with their N-termini in cytoplasm and their C-termini in periplasm, were used for fusion expression. The recombinant production of two peptides, asteropsin A (ASPA) and 관-defensin (BD), was induced in the periplasm of E. coli using a selected carrier protein. Both peptides were expressed at high levels, at yields of approximately 5-10 mg/L of culture. Mass spectrometry showed that the resulting peptide had the same molecular weight as their natural forms. After purification, single peaks were observed by reversed phase high-performance liquid chromatography (RP-HPLC), demonstrating the absence of isoforms. Furthermore, cytoplasmically expressed fusion proteins with a carrier at their C-termini did not contain disulfide bonds. This study provides new carrier proteins for fusion expression of disulfide bond-rich peptides in E. coli.</P>
Ziwei Chang,박장수,Ming Lu,Sung-Min Park,Hyun-Kyung Park,강호성,박영상 한국분자세포생물학회 2012 Molecules and cells Vol.33 No.5
The present study highlighted the aromatic-participant interactions in in vivo trimerization of HSF1 and got an insight into the process of HSF1 protecting against apoptosis. In mouse embryonic fibroblasts (MEFs), mutations of mouse HSF1 (W37A, Y60A and F104A) resulted in a loss of trimerization activity, impaired binding of the heat shock element (HSE) and lack of heat shock protein 70 (HSP70) expression after a heat shock. Under UV irradiation, wild-type mouse HSF1 protected the MEFs from UV-induced apoptosis, but none of the mutants offered protection. We found that normal expression of HSF1 was essential to the cell arrest in G2 phase, assisting with the cell cycle checkpoint. The cells that lack normal HSF1 failed to arrest in the G2 phase, resulting in the process of cell apoptosis. We conclude that the treatment with UV or heat shock stre-sses appears to induce the approach of HSF1 monomers directly via aromatic-participant interactions, followed by the formation of a HSF1 trimer. HSF1 protects the MEFs from the stresses through the expression of HSPs and a G2 cell cycle arrest.
Lu, Ming,Chang, Ziwei,Park, Jang-Su Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.11
The activation of heat shock factor 1 (HSF1) can be induced by the changes in environmental pH, but the mechanism of HSF1 activation by acidification is not completely understood. This paper reports that a low pH (pH~6.0) can trigger human HSF1 activation. Considering the involvement of the imidazole group of histidine residues under acid pH stress, an in vitro EMSA experiment, Trp-fluorescence spectroscopy, and protein structural analysis showed that the residue, His83, is the essential for pH-dependent human HSF1-activation. To determine the roles of His83 in the HSF1-mediated stress response affecting the cellular acid resistance, mouse embryo fibroblasts with normal wild-type or mutant mouse HSF1 expression were preconditioned by heating or pH stress. The results suggest that His83 is essential for HSF1 activation or the HSF1-mediated transcription of heat shock proteins, in protecting cells from acid pH stress.
Ming Lu,Ziwei Chang,박장수 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.11
The activation of heat shock factor 1 (HSF1) can be induced by the changes in environmental pH, but the mechanism of HSF1 activation by acidification is not completely understood. This paper reports that a low pH (pH~6.0) can trigger human HSF1 activation. Considering the involvement of the imidazole group of histidine residues under acid pH stress, an in vitro EMSA experiment, Trp-fluorescence spectroscopy, and protein structural analysis showed that the residue, His83, is the essential for pH-dependent human HSF1-activation. To determine the roles of His83 in the HSF1-mediated stress response affecting the cellular acid resistance, mouse embryo fibroblasts with normal wild-type or mutant mouse HSF1 expression were preconditioned by heating or pH stress. The results suggest that His83 is essential for HSF1 activation or the HSF1-mediated transcription of heat shock proteins, in protecting cells from acid pH stress.
Kim, So-Sun,Chang, Ziwei,Park, Jang-Su Elsevier 2015 FISH AND SHELLFISH IMMUNOLOGY Vol.43 No.2
<P><B>Abstract</B></P> <P>Heat shock proteins (HSPs) are synthesized rapidly in response to a variety of physiological or environmental stressors, whereas the transcriptional activation of HSPs is regulated by a family of heat shock factors (HSFs). In vertebrates, multiple HSFs (HSF1-4) have been reported to have different roles in response to a range of stresses. This paper reports the cDNA cloning of two goldfish (<I>Carassius auratus</I>) HSF gene families, HSF1 and three isoforms of HSF2. Both HSF1 and HSF2s showed high homology to the known HSFs from other organisms, particularly the zebrafish. Different patterns of HSF1 and HSF2 mRNA expression were detected in several goldfish tissues, highlighting their distinct roles. In cadmium (Cd)-treated tissues, the responses of HSP70 showed less difference. However, the increase in HSF1 and HSF2 in these tissues differs considerable. In particular, HSF2 was induced strongly in the heart and liver. On the other hand, in heart tissue, HSF1 showed the smallest increment. These results suggest the potential role of HSF2 in assisting HSF1 in these tissues. In another in?vitro experiment of hepatocyte cultures, Cd exposure caused similar patterns of goldfish HSF1 and HSF2 mRNA expression and induction of the HSP70 protein. On the other hand, an examination of the characterization of recombinant proteins showed that HSF1 undergoes a conformation change induced by heat shock above 30?°C and approaches each other in the trimer, whereas HSF2 could not sense thermal stress directly.</P> <P>Furthermore, immune-blot analysis of HSFs showed that both monomers and trimmers of HSF1 were observed in cadmium-induced tissues, whereas HSF2 were all in monomeric. These results show that HSF1 and HSF2 play different roles in the transcription of heat shock proteins.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The cDNA of Goldfish HSF1 and three isoforms of HSF2 were cloned. </LI> <LI> Different patterns of HSF1 and HSF2 mRNA expression were detected. </LI> <LI> In hepatocytes, Cd caused similar patterns of HSF1 and HSF2 mRNA expression. </LI> <LI> There is a distinct difference between two factors in the protein patterns of the HSF1 and HSF2 by Cd exposure. </LI> <LI> HSF1 and HSF2 play different roles in the transcription of heat shock proteins by thermal stress. </LI> </UL> </P>
Yunqi Ma,Ming Lu,Ziwei Chang,이추,유해균,박장수 한국생물공학회 2018 Biotechnology and Bioprocess Engineering Vol.23 No.1
Cytochrome P4501A (CYP1A) has attracted an increasing interest due to its important role in metabolism of contaminants in aquatic environment and kinds of biomarkers to monitor the pollutants. CYPs are reported to express in E. coli, yeast and insect cells, while expression levels in these systems are too low to continue further study, such as functional and structural research. In this study, we construct an expression system using Shewanella oneidensis to produce goldfish CYP1A. RBS sequence that can elevate expression level by initiating the translation was added. A leading signal peptide which will direct the goal protein into periplasm of the host was introduced. Moreover, large-size plasmid construction strategy was applied during the successful construction process of expression system. At the position of ~60 kDa, a single band was seen clearly after expression; furthermore the amount of expressed CYP1A was as high as 0.02 micromoles per liter in the culture. Heme test was also performed, the result showed the typical P450 hemoprotein spectra. All these data suggest the possible suitable expression system for fish P4501A system was constructed.