Production of (S)-3-hydroxybutyrate by metabolically engineered Saccharomyces cerevisiae

Yun, E.J.,Kwak, S.,Kim, S.R.,Park, Y.C.,Jin, Y.S.,Kim, K.H. Elsevier Science Publishers 2015 Journal of biotechnology Vol.209 No.-

(S)-3-Hydroxybutyrate (S-3HB) can be used as a precursor for the synthesis of biodegradable polymers such as polyhydroxyalkanoate and stereo-specific fine chemicals such as antibiotics, pheromones, and drugs. For the production of S-3HB in yeast, the biosynthetic pathway of S-3HB from acetyl-CoA, consisting of the three enzymes, acetyl-CoA C-acetyltransferase (ACCT), acetoacetyl-CoA reductase (ACR), and 3-hydroxybutyryl-CoA thioesterase (HBT), was introduced into Saccharomyces cerevisiae. An engineered yeast strain overexpressing ERG10, hbd, and tesB genes not only exhibited enzyme activities of AACT, ACR, and HBT, but also produced S-3HB from ethanol. In order to increase the titer of S-3HB, a fed-batch fermentation based on pulse feeding of ethanol as a carbon source was performed, and a final S-3HB titer of 12.0g/L was achieved. This is the first report on the production of 3HB by engineered yeast, utilizing ethanol as the carbon source, suggesting that the industrially preferred S. cerevisiae can be a promising host for producing S-3HB.

S100A2 promoter-driven conditionally replicative adenovirus targets non-small-cell lung carcinoma

Lee, K,Yun, S-T,Yun, C-O,Ahn, B-Y,Jo, E-C Macmillan Publishers Limited 2012 Gene Therapy Vol.19 No.10

S100A2, a member of the S100 family of calcium-binding proteins, has been implicated in carcinogenesis as both a tumor suppressor and stimulator. Here, we characterized promoter activity of S100A2, generated an S100A2 promoter-driven conditionally replicative adenovirus (Ad/SA), and evaluated its anti-tumor activity in vitro and in vivo. Promoter activity of S100A2 was greatly restricted to tumor cells, and the S100A2 promoter bound with typical nuclear targets of epidermal growth factor receptor (EGFR) signaling. EGF-stimulated EGFR phosphorylation induced S100A2 expression and further activated E1A expression of Ad/SA, which was restored by EGFR signal inhibition in a concentration-dependent manner in non-small-cell lung carcinoma (NSCLC). In two EGFR-activated tumor xenograft animal models, Ad/SA exhibited potent anti-tumor activity, whereas cetuximab, an EGFR-targeting anticancer drug, was active transiently or ineffective. Combined treatment with cetuximab or cisplatin plus Ad/SA resulted in enhanced anti-tumor activity. Immunohistochemical analysis of tumor sections showed moderate-to-high grade signals for EGFR and adenovirus, and a reduction in viable cells in Ad/SA-treated tumors. Collectively, these results demonstrate that the S100A2 promoter-driven adenovirus is a potent inhibitor of cancers, and further suggest that S100A2 is a target gene of EGFR signaling pathway in NSCLC.

<i>S100A9</i> and <i>EGFR</i> gene signatures predict disease progression in muscle invasive bladder cancer patients after chemotherapy

Kim, W. T.,Kim, J.,Yan, C.,Jeong, P.,Choi, S. Y.,Lee, O. J.,Chae, Y. B.,Yun, S. J.,Lee, S. C.,Kim, W. J. Oxford University Press 2014 Annals of Oncology Vol.25 No.5

<P>In our previous gene expression profile analysis, IL1B, S100A8, S100A9, and EGFR were shown to be important mediators of muscle invasive bladder cancer (MIBC) progression. The aim of the present study was to investigate the ability of these gene signatures to predict disease progression after chemotherapy in patients with locally recurrent or metastatic MIBC. Patients with locally advanced MIBC who received chemotherapy were enrolled. The expression signatures of four genes were measured and carried out further functional analysis to confirm our findings. Two of the four genes, S100A9 and EGFR, were determined to significantly influence disease progression (P = 0.023, 0.045, respectively). Based on a receiver operating characteristic curve, a cut-off value for disease progression was determined. Patients with the good-prognostic signature group had a significantly longer time to progression and cancer-specific survival time than those with the poor-prognostic signature group (P < 0.001, 0.042, respectively). In the multivariate Cox regression analysis, gene signature was the only factor that significantly influenced disease progression [hazard ratio: 4.726, confidence interval: 1.623-13.763, P = 0.004]. In immunohistochemical analysis, S100A9 and EGFR positivity were associated with disease progression after chemotherapy. Protein expression of S100A9/EGFR showed modest correlation with gene expression of S100A9/EGFR (r = 0.395, P = 0.014 and r = 0.453, P = 0.004). Our functional analysis provided the evidence demonstrating that expression of S100A9 and EGFR closely associated chemoresistance, and that inhibition of S100A9 and EGFR may sensitize bladder tumor cells to the cisplatin-based chemotherapy. The S100A9/EGFR level is a novel prognostic marker to predict the chemoresponsiveness of patients with locally recurrent or metastatic MIBC.</P>

Biochemical analysis of recombinant CYP4A11 allelic variant enzymes: W126R, K276T and S353G

Han, S.,Cha, G.S.,Chun, Y.J.,Lee, C.H.,Kim, D.,Yun, C.H. JAPANESE SOCIETY FOR THE STUDY OF XENOBIOTICS 2016 DRUG METABOLISM AND PHARMACOKINETICS Vol.31 No.6

Human CYP4A11 is the major ω-hydroxylase of fatty acids in the liver and kidneys. It produces 20-hydroxyeicosatetraenoic acid as well as hydroxylates fatty acids. In this study, we investigated the biochemical properties of three alleles of CYP4A11: W126R, K276T, and S353G. Site-directed mutagenesis of the wild type CYP4A11 was performed, to construct the W126R, K276T, and S353G variant clones. The CYP4A11 wild type and variant constructs were heterologously expressed in Escherichia coli. CO-binding spectra showed the expression of the wild type, K276T and S353G variants, indicating the functional P450 holoenzyme. The W126R variant was not expressed in E. coli. Binding affinities of lauric acid in K276T and S353G variants were stronger than that of wild type. Steady-state kinetics in the hydroxylation reaction of fatty acids were studied. The catalytic efficiencies (k<SUB>cat</SUB>/K<SUB>m</SUB>) of K276T and S353G variants in the reactions without cytochrome b<SUB>5</SUB> were approximately 2- and 4-fold higher, respectively, than that of wild type, and in the reactions with cytochrome b<SUB>5</SUB> they were approximately 2- and 3-fold higher, respectively. These results suggest that individuals carrying the alleles, K276T and S353G, might exhibit higher catalysis of CYP4A11, which may affect the endogenous metabolic products associated with regulation of blood pressure.

Streptococcus gordonii induces nitric oxide production through its lipoproteins stimulating Toll-like receptor 2 in murine macrophages

Kim, H.Y.,Baik, J.E.,Ahn, K.B.,Seo, H.S.,Yun, C.H.,Han, S.H. Pergamon Press 2017 Molecular immunology Vol.82 No.-

<P>Streptococcus gordonii, a Gram-positive commensal in the oral cavity, is an opportunistic pathogen that can cause endodontic and systemic infections resulting in infective endocarditis. Lipoteichoic acid (LTA) and lipoprotein are major virulence factors of Gram-positive bacteria that are preferentially recognized by Toll-like receptor 2 (TLR2) on immune cells. In the present study, we investigated the effect of S. gordonii LTA and lipoprotein on the production of the representative inflammatory mediator nitric oxide (NO) by the mouse macrophages. Heat-killed S. gordonii wild-type and an LTA-deficient mutant (Delta ltaS) but not a lipoprotein-deficient mutant (Delta lgt) induced NO production in mouse primary macrophages and the cell line, RAW 264.7.S. gordonii wild-type and Delta ItaS also induced the expression of inducible NO synthase (iNOS) at the mRNA and protein levels. In contrast, the Delta lgt mutant showed little effect under the same condition. Furthermore, S. gordonii wild-type and Delta ItaS induced NF-kappa B activation, STAT1 phosphorylation, and IFN-beta expression, which are important for the induction of iNOS gene expression, with little activation by Delta lgt. S. gordonii wild-type and Delta ltaS showed an increased adherence and internalization to RAW 264.7 cells compared to Delta lgt. In addition, S. gordonii wild-type and AIMS, but not Delta lgt, substantially increased TLR2 activation while none of these induced NO production in TLR2-deficient macrophages. Triton X-114-extracted lipoproteins from S. gordonii were sufficient to induce NO production. Collectively, we suggest that lipoprotein is an essential cell wall component of S. gordonii to induce NO production in macrophages through TLR2 triggering NF-kappa B and STAT1 activation. (C) 2016 Elsevier Ltd. All rights reserved.</P>

濟州道 原乳의 季節別, 飼育規模別 成分 變化에 關한 硏究

李賢鐘,梁昇柱,朴喜錫,尹瑛斌 濟州大學校 새마을硏究所 1988 새마을硏究論文集 Vol.5 No.-

The study was conducted to analyze components of raw milk, seasonal variation and correlation between components, and to obtain fundamental data in developing the quaity of raw milk and of feeding management, surveying 3 districts by milk-collecting area and 4 groups farm size between March of 1986 to February of 1987, and the results obtained are as follows; 1. Fat and T.S. were low in spring and summer and S.N.F. was low in summer, protein and lactose showed however, no significant seasonal variation. 2. The correlations between fat and T. S.(r= + 0.599004 in spring (r=+ 0.877195 in winter) fat and S. N. F. (r=+ 0.206696 in winter, r = + 0.829499 in spring) and S. N. F. and T. S. ( r= + 0.286247 in spring, r = + 0.812476 in winter) were significant in components by season. 3. On component veriation by from size, fat component highest in the group of 6-10 head, and the larger the farm size was, the higher the fat component was, and T. S. showed the same pattern as this, lactose and protein were not signigicant by farm size. 4. Fat component was 3.73-3.83%, protein 3.17-3.23%, lactose 4.54-4.63%, S.N.F. 8.66-8.71%, and T. S. 12.41-12.56% by area, and there was no variation between areas.

Comparison of mRNA, Protein, and Urinary Nucleic Acid Levels of S100A8 and S100A9 between Prostate Cancer and BPH

Yun, S. J.,Yan, C.,Jeong, P.,Kang, H. W.,Kim, Y. H.,Kim, E. A.,Lee, O. J.,Kim, W. T.,Moon, S. K.,Kim, I. Y. Springer Science + Business Media 2015 Annals of Surgical Oncology Vol.22 No.7

Melatonin enhances arsenic trioxide-induced cell death via sustained upregulation of Redd1 expression in breast cancer cells

Yun, S.M.,Woo, S.H.,Oh, S.T.,Hong, S.E.,Choe, T.B.,Ye, S.K.,Kim, E.K.,Seong, M.K.,Kim, H.A.,Noh, W.C.,Lee, J.K.,Jin, H.O.,Lee, Y.H.,Park, I.C. North-Holland 2016 Molecular and cellular endocrinology Vol.422 No.-

Melatonin is implicated in various physiological functions, including anticancer activity. However, the mechanism(s) of its anticancer activity is not well understood. In the present study, we investigated the combined effects of melatonin and arsenic trioxide (ATO) on cell death in human breast cancer cells. Melatonin enhanced the ATO-induced apoptotic cell death via changes in the protein levels of Survivin, Bcl-2, and Bax, thus affecting cytochrome c release from the mitochondria to the cytosol. Interestingly, we found that the cell death induced by co-treatment with melatonin and ATO was mediated by sustained upregulation of Redd1, which was associated with increased production of reactive oxygen species (ROS). Combined treatment with melatonin and ATO induced the phosphorylation of JNK and p38 MAP kinase downstream from Redd1 expression. Rapamycin and S6K1 siRNA enhanced, while activation of mTORC1 by transfection with TSC2 siRNA suppressed the cell death induced by melatonin and ATO treatment. Taken together, our findings suggest that melatonin enhances ATO-induced apoptotic cell death via sustained upregulation of Redd1 expression and inhibition of mTORC1 upstream of the activation of the p38/JNK pathways in human breast cancer cells.

표면항원 및 유전자분석에 의한 V. vulnificus균의 계통분류학적 연구(Ⅰ) : 지방산 조성 및 RAPD PCR에 의한 V. vulnificus균의 계통분류학적 연구

윤영희,김기상,신영학,이점규,오경수,유정식,이상원,이근용 국립보건연구원 1998 국립보건원보 Vol.35 No.-

생체 신장이식 1,000예 시행중 관찰된 비뇨기계 합병증과 외과적 치료에 관한 고찰

윤성현,김유선,오창권,김용신,양승철,박기일 大韓移植學會 1993 Korean Journal of Transplantation Vol.7 No.1