The E. coli sirtuin CobB shows no preference for enzymatic and nonenzymatic lysine acetylation substrate sites Journal Article

Authors: Abouelfetouh, A; Kuhn, M. L.; Hu, L. I.; Scholle, M. D.; Sorensen, D. J.; Sahu, A. K.; Becher, D.; Antelmann, H.; Mrksich, M.; Anderson, W. F.; Gibson, B. W.; Schilling, B; Wolfe, A. J.
Article Title: The E. coli sirtuin CobB shows no preference for enzymatic and nonenzymatic lysine acetylation substrate sites
Abstract: N(epsilon) -lysine acetylation is an abundant posttranslational modification of thousands of proteins involved in diverse cellular processes. In the model bacterium Escherichia coli, the epsilon-amino group of a lysine residue can be acetylated either catalytically by acetyl-coenzyme A (acCoA) and lysine acetyltransferases, or nonenzymatically by acetyl phosphate (acP). It is well known that catalytic acCoA-dependent N(epsilon) -lysine acetylation can be reversed by deacetylases. Here, we provide genetic, mass spectrometric, structural and immunological evidence that CobB, a deacetylase of the sirtuin family of NAD(+) -dependent deacetylases, can reverse acetylation regardless of acetyl donor or acetylation mechanism. We analyzed 69 lysines on 51 proteins that we had previously detected as robustly, reproducibly, and significantly more acetylated in a cobB mutant than in its wild-type parent. Functional and pathway enrichment analyses supported the hypothesis that CobB regulates protein function in diverse and often essential cellular processes, most notably translation. Combined mass spectrometry, bioinformatics, and protein structural data provided evidence that the accessibility and three-dimensional microenvironment of the target acetyllysine help determine CobB specificity. Finally, we provide evidence that CobB is the predominate deacetylase in E. coli.
Journal Title: MicrobiologyOpen
Volume: 4
Issue: 1
ISSN: 2045-8827; 2045-8827
Publisher: The Authors. MicrobiologyOpen published by John Wiley Sons Ltd  
Journal Place: England
Date Published: 2015
Start Page: 66
End Page: 83
Language: eng
Notes: LR: 20150305; CI: (c) 2014; GR: R24 DK085610/DK/NIDDK NIH HHS/United States; GR: S10 OD016281/OD/NIH HHS/United States; JID: 101588314; OID: NLM: PMC4335977; OTO: NOTNLM; 2014/07/31 [received]; 2014/10/21 [revised]; 2014/10/24 [accepted]; 2014/11/22 [aheadofprint]; ppublish