Structural insights into the substrate specificity of the Rhodopseudomonas palustris protein acetyltransferase RpPat: identification of a loop critical for recognition by RpPat.

ABSTRACT: Lysine acetylation is a post-translational modification that is important for the regulation of metabolism in both prokaryotes and eukaryotes. In bacteria, the best studied protein acetyltransferase is Pat. In the purple photosynthetic bacterium Rhodopseudomonas palustris, at least 10 AMP-forming acyl-CoA synthetase enzymes are acetylated by the Pat homologue RpPat. All bona fide RpPat substrates contain the conserved motif PX(4)GK. Here, we show that the presence of such a motif is necessary but not sufficient for recognition by RpPat. RpPat failed to acetylate the methylmalonyl-CoA synthetase of this bacterium (hereafter RpMatB) in vivo and in vitro, despite the homology of RpMatB to known RpPat substrates. We used RpMatB to identify structural determinants that are recognized by RpPat.

SUBMITTER: Crosby HA 

PROVIDER: S-EPMC3510837 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature