Continuous culture and proteomic analysis of Escherichia coli DH5α and its acetate-tolerant mutant DA19 under conditions of nitrogen source limitation.
Escherichia coli DH5α grows poorly in a chemically defined medium, but its acetate-tolerant mutant, DA19, grows fast and produces less acetate. To investigate the differences in metabolism between the two strains, the samples of continuous cultures at steady state were analyzed by two-dimensional SDS-PAGE (2-D SDS-PAGE) and peptide mass fingerprinting (PMF). The results indicated that in DA19, expression of gnd, yddS, and purH (except for adenine supplement) was up-regulated, and expression of atpA, glnK, and ompR, which encode membrane proteins, was significantly up-regulated. Expression of ackA and yahK in DA19 was down-regulated. In the presence of acetate, hchA and ydcW in DH5α were significantly down-regulated. This study shed light on the differences in metabolic properties between DH5α and DA19, and provided some ideas for improving strains through metabolic engineering.
Zhang
Xiaoyun
X
State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China.
Zhang
Yanjun
Y
Li
Zhimin
Z
Xia
Yuelan
Y
Ye
Qin
Q
D000085:Acetates / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000096:biosynthesis* / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics; D009154:Mutation; D009584:Nitrogen; D020543:Proteome / Q000096:biosynthesis* / Q000235:genetics; D040901:Proteomics
D000085:Acetates; D029968:Escherichia coli Proteins; D020543:Proteome; D009584:Nitrogen