RRC ID 4931
著者 Nanchen A, Schicker A, Revelles O, Sauer U.
タイトル Cyclic AMP-dependent catabolite repression is the dominant control mechanism of metabolic fluxes under glucose limitation in Escherichia coli.
ジャーナル J Bacteriol
Abstract Although a whole arsenal of mechanisms are potentially involved in metabolic regulation, it is largely uncertain when, under which conditions, and to which extent a particular mechanism actually controls network fluxes and thus cellular physiology. Based on (13)C flux analysis of Escherichia coli mutants, we elucidated the relevance of global transcriptional regulation by ArcA, ArcB, Cra, CreB, CreC, Crp, Cya, Fnr, Hns, Mlc, OmpR, and UspA on aerobic glucose catabolism in glucose-limited chemostat cultures at a growth rate of 0.1 h(-1). The by far most relevant control mechanism was cyclic AMP (cAMP)-dependent catabolite repression as the inducer of the phosphoenolpyruvate (PEP)-glyoxylate cycle and thus low tricarboxylic acid cycle fluxes. While all other mutants and the reference E. coli strain exhibited high glyoxylate shunt and PEP carboxykinase fluxes, and thus high PEP-glyoxylate cycle flux, this cycle was essentially abolished in both the Crp and Cya mutants, which lack the cAMP-cAMP receptor protein complex. Most other mutations were phenotypically silent, and only the Cra and Hns mutants exhibited slightly altered flux distributions through PEP carboxykinase and the tricarboxylic acid cycle, respectively. The Cra effect on PEP carboxykinase was probably the consequence of a specific control mechanism, while the Hns effect appears to be unspecific. For central metabolism, the available data thus suggest that a single transcriptional regulation process exerts the dominant control under a given condition and this control is highly specific for a single pathway or cycle within the network.
巻・号 190(7)
ページ 2323-30
公開日 2008-4-1
DOI 10.1128/JB.01353-07
PII JB.01353-07
PMID 18223071
PMC PMC2293195
MeSH Biomass Carbon Isotopes Citric Acid Cycle / drug effects Cyclic AMP / metabolism* Escherichia coli / genetics Escherichia coli / growth & development Escherichia coli / metabolism* Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism* Gene Expression Regulation, Bacterial / drug effects Glucose / metabolism* Glucose / pharmacology Glyoxylates / metabolism Models, Biological Mutation Phosphoenolpyruvate / metabolism Transcription, Genetic / drug effects
IF 3.006
引用数 53
WOS 分野 MICROBIOLOGY
リソース情報
原核生物(大腸菌) ME9062(BW25113) JW4364 JW3177 JW0078 JW4361 JW4362 JW3320 JW3778 JW1328 JW1225 JW1586 JW3368 JW3462