文献类型：期刊文献

英文题名：Production of succinate by a pflB ldhA double mutant of Escherichia coli overexpressing malate dehydrogenase

作者：Wang, Wei[1];Li, Zhimin[1];Xie, Jingli[1];Ye, Qin[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2009

卷号：32

期号：6

起止页码：737

外文期刊名：BIOPROCESS AND BIOSYSTEMS ENGINEERING

收录：;EI(收录号：20093612283007);WOS:【SCI-EXPANDED(收录号:WOS:000269186400005)】；

基金：We thank Professor David P. Clark for kindly providing us with the strain NZN111. This work was supported by the Natural Science Foundation of China, No. 20576032, and partially supported by the Project of Shanghai Leading Academic Disciplines, No. B505.

语种：英文

外文关键词：Escherichia coli; Malate dehydrogenase; Bicarbonate; Succinic acid; Two-stage culture

摘要：The gene encoding malate dehydrogenase (MDH) was overexpressed in a pflB ldhA double mutant of Escherichia coli, NZN111, for succinic acid production. With MDH overexpression, NZN111/pTrc99A-mdh restored the ability to metabolize glucose anaerobically and 0.55 g/L of succinic acid was produced from 3 g/L of glucose in shake flask culture. When supplied with 10 g/L of sodium bicarbonate (NaHCO3), the succinic acid yield of NZN111/pTrc99A-mdh reached 1.14 mol/mol glucose. Supply of NaHCO3 also improved succinic acid production by the control strain, NZN111/pTrc99A. Measurement of key enzymes activities revealed that phosphoenolpyruvate (PEP) carboxykinase and PEP carboxylase in addition to MDH played important roles. Two-stage culture of NZN111/pTrc99A-mdh was carried out in a 5-L bioreactor and 12.2 g/L of succinic acid were produced from 15.6 g/L of glucose. Fed-batch culture was also performed, and the succinic acid concentration reached 31.9 g/L with a yield of 1.19 mol/mol glucose.