cAMP‐CRP co‐ordinates the expression of the protein acetylation pathway with central metabolism in Escherichia coli

Abstract

SummaryLysine acetylation is a well-established posttranslational modification widely conserved and distributed in bacteria. Although multiple regulatory roles have been proved, little is known about its regulation. Here, we present evidence that the transcription of the Gcn5-like acetyltransferase YfiQ of Escherichia coli (proposed name: PatZ) is regulated by cAMP-CRP and its implications on acetate metabolism regulation. The acetate scavenging acetyl-CoA synthetase (Acs) is regulated at the transcriptional and post-translational levels. Post-translational regulation depends on a protein acetyltransferase (yfiQ) and an NAD + -dependent deacetylase (cobB). We have studied their expression under different environmental conditions. cobB is constitutively expressed from a promoter located upstream nagK. The expression of yfiQ occurs from its own promoter; it is upregulated in the stationary phase and in the presence of non-PTS carbon sources and is positively regulated by cAMP-CRP. Two putative CRP binding sites are necessary for its full activity. Gene deletion revealed that cobB is essential for growth on acetate, yfiQ deletion restoring growth of the cobB mutant. The fine tuning of metabolic enzymes results from the integration of multiple mechanisms, and redundant systems may exist. Despite the existence of divergent catabolite repression systems, this may be a conserved strategy common to both Gram-positive and -negative bacteria.

Acylation of Biomolecules in Prokaryotes: a Widespread Strategy for the Control of Biological Function and Metabolic Stress

“…Since its discovery, it has been shown that RLA controls Acs and other members of the acyl-CoA synthetases via acetylation and that this regulatory mechanism of metabolism is present in prokaryotes and eukaryotes (29,176). Acetylation of Acs homologues by SePat homologues has also been demonstrated in E. coli (141,177), R. palustris (69), B. subtilis (30), Streptomyces spp. (31), and Mycobacterium spp.…”

Allosteric Regulation of a Protein Acetyltransferase in Micromonospora aurantiaca by the Amino Acids Cysteine and Arginine

“…In prokaryotes, some acetyltransferases for protein acetylation have been investigated, including SePat in S. enterica (15), EcPatZ in E. coli (4), RpPat in Rhodopseudomonas palustris (16), MtKat in M. uberculosis, MsKat in M. smegmatis (6), and SlPatA in Streptomyces lividans (17). These protein acetyltransferases containing a GNAT domain can acetylate acetyl-CoA synthetases.…”

“…In the enteric bacteria E. coli, the transcription of protein acetyltransferase PatZ is controlled at the transcriptional level in response to the intracellular cAMP signal. The catabolite activator protein-cAMP complex binds to two sites in the patZ promoter and induces the expression of genes that increase the level of acetylated proteins (4). The activity of protein acetyltransferases is also controlled by allosteric effects.…”

Global dynamics of Escherichia coli phosphoproteome in central carbon metabolism under changing culture conditions

“…The enzyme PatZ directly acetylates isocitrate lyase (AceA) and maybe isocitrate dehydrogenase phosphatase (AceK). The expression of patZ is regulated by catabolite repression, while cobB is constitutively expressed [71]. Findings of changing phosphorylation patterns in Mdh, Pck and AcnB contribute to demonstrate the tight mechanism of regulation by post-translational modification in the E. coli central carbon metabolism.…”