Substrate-induced conformational changes in the essential peripheral membrane-associated mannosyltransferase PimA from mycobacteria: implications for catalysis.

ABSTRACT: Phosphatidyl-myo-inositol mannosyltransferase A (PimA) is an essential glycosyltransferase (GT) involved in the biosynthesis of phosphatidyl-myo-inositol mannosides (PIMs), which are key components of the mycobacterial cell envelope. PimA is the paradigm of a large family of peripheral membrane-binding GTs for which the molecular mechanism of substrate/membrane recognition and catalysis is still unknown. Strong evidence is provided showing that PimA undergoes significant conformational changes upon substrate binding. Specifically, the binding of the donor GDP-Man triggered an important interdomain rearrangement that stabilized the enzyme and generated the binding site for the acceptor substrate, phosphatidyl-myo-inositol (PI). The interaction of PimA with the beta-phosphate of GDP-Man was

SUBMITTER: Guerin ME 

PROVIDER: S-EPMC2755885 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature