Metabolic characterisation of E-coli citrate synthase and phosphoenolpyruvate carboxylase mutants in aerobic cultures

被引：16

作者：

De Maeseneire, S. L. ^{[1
]}

De Mey, M. ^{[1
]}

Vandedrinck, S. ^{[1
]}

Vandamme, E. J. ^{[1
]}

机构：

[1] Univ Ghent, Dept Biochem & Microbial Technol, Lab Ind Microbiol & Biocatalysis, B-9000 Ghent, Belgium

来源：

BIOTECHNOLOGY LETTERS | 2006年 / 28卷 / 23期

关键词：

acetate reduction; Escherichia coli; gltA; metabolic engineering; ppc;

D O I：

10.1007/s10529-006-9182-8

中图分类号：

Q81 [生物工程学（生物技术）]; Q93 [微生物学];

学科分类号：

071005 ; 0836 ; 090102 ; 100705 ;

摘要：

E. coli is still one of the most commonly used hosts for protein production. However, when it is grown with excess glucose, acetate accumulation occurs. Elevated acetate concentrations have an inhibitory effect on growth rate and recombinant protein yield, and thus elimination of acetate formation is an important aim towards industrial production of recombinant proteins. Here we examine if over-expression of citrate synthase (gltA) or phosphoenolpyruvate carboxylase (ppc) can eliminate acetate production. Knock-out as well as over-expression mutants were constructed and characterized. Knocking out ppc or gltA decreased the maximum cell density by 14% and increased the acetate excretion by 7%, respectively decreased it by 10%. Over-expression of ppc or gltA increased the maximum cell dry weight by 91% and 23%, respectively. No acetate excretion was detected at these increased cell densities (35 and 23 g/l, respectively).

引用

页码：1945 / 1953

页数：9

共 16 条

[1] The pKNOCK series of broad-host-range mobilizable suicide vectors for gene knockout and targeted DNA insertion into the chromosome of Gram-negative bacteria [J].