报告题目：Engineering of Glycolytic Pathways in Escherichia coli for Co-production of Hydrogen and Ethanol from Glucose

　　报 告 人：Prof. Sunghoon Park

　　工作单位：Pusan National University, South Korea

　　报告时间：2015年11月5日（星期四）15:30-16:30

　　报告地点：行政楼205报告厅

　　报告人简介：

　　I. EDUCATION

　　1976 - 1980, Seoul National University, Korea, B.S., Chemical Technology

　　1980 - 1982, Seoul National University, Korea, M.S., Chemical Technology

　　1984 - 1988, University of California,Davis, CA, Ph.D., Chemical Engineering

　　II. EXPERIENCES

　　03/1991 - present: Professor of Chemical and Biomolecular Engineering, Pusan National University (PNU), Korea

　　09/2012 - 08/2014: External Examiner, Univ. Malaya, Dept. Biotechnol.

　　01/2010 - present: Adjunct Professor, East China Univ. of Science and Technol., Dept. Biotechnol., Shanghai, China

　　01/2009 - 12/2014: Editor-in-Chief, Biotechnol and Bioprocess Eng (BBE)

　　08/2010 - present: Senior Editor, J. Industrial Microbiology & Biotechnology

　　08/2008 - 08/2011: Dean, Office of International Affairs, PNU

　　11/2006 - 07/2008: Director, Institute for Environmental Studies, PNU

　　06/2002 - 05/2005: Director, Institute for Environmental Technology and Industry

　　10/1988 - 02/1991: Research Staff, Chemical and Biomedical Sciences Division, Lawrence Livermore National Laboratory, CA

　　10/1982 - 08/1984: Research Engineer, CKD pharmaceutical Co., Seoul, Korea

　　III. PROFESSIONAL MEMBERSHIPS

　　Korean Society for Biotechnology and Bioengineering

　　Korean Institute of Chemical Engineers

　　American Society for Microbiology

　　Society for Industrial Microbiology and Biotechnology, USA

　　IV. PUBLICATIONS

　　Over 150 papers in peer-reviewed journals and about 30 patents in the field of biochemical engineering and biotechnology.

　　V. CURRENT RESEARCH INTERESTS

　　Metabolic engineering, enzyme engineering, system biology and microbial fermentation for: Biological production of 3-hydroxypropionic acid (3-HP) and 1,3-propanediol from glycerol; and biological hydrogen production

　　Park's homepage: http://bcelab.pusan.ac.kr

　　报告摘要：

　　Biologically, hydrogen (H₂) can be produced from glucose through dark fermentation and photo-fermentation. Hydrogen production by dark fermentation is fast and simple, but gives low theoretical yield of 2-4 mol H₂/mol glucose. Co-production of H₂ and ethanol, both of which are good biofuels, has been suggested as a solution to this problem. To prove the feasibility, glucose assimilation in Escherichia coli was modified by eliminating phosphofructokinase (pfkA) or phosphoglucose isomerase (pgi) in Embden-Meyhof-Parnas (EMP) pathway and/or 6-phosphogluconate dehydratase (edd) and/or 2-keto-3deoxy-6-phosphogluconate aldolase (eda) in Entner-Doudoroff (ED) pathway. In addition, the pentose-phosphate (PP) pathway, which can generate more NADPH than the EMP or ED pathway, was fortified by overexpressing two key enzymes, Zwf and Gnd, present at the node of glycolytic pathway branches. The strains without overexpression of Zwf and/or Gnd did not show improved performance because glucose metabolism largely stopped at the pyruvate node. In comparison, when Zwf and/or Gnd were overexpressed in E. coli strains devoid of pfkA, pgi, edd-eda and/or pta-ack, co-production of H₂ and ethanol was significantly improved with the concomitant reduction of pyruvate secretion. Gene expression and metabolic flux analyses showed that, upon overexpression of Zwf and Gnd, role of the PP pathway for glucose assimilation relative to that of EMP or ED pathway was greatly enhanced. The maximum co-production yields were 1.71 mol H₂/mol glucose and 1.41 mol ethanol/mol glucose, respectively. This study suggests that the robust central carbon metabolisms and the amount of NAD(P)H formed under anaerobic conditions can be altered by modifying (the activity of) several key enzymes.