MmpA, a conserved membrane protein required for efficient surface transport of trehalose lipids in corynebacterineae

Abstract

Cell walls of bacteria of the genera Mycobacterium and Corynebacterium contain high levels of (coryno)mycolic acids. These very long chain fatty acids are synthesized on the cytoplasmic leaf-let of the inner membrane (IM) prior to conjugation to the disaccharide, trehalose, and transport to the periplasm. Recent studies on Corynebacterium glutamicum have shown that acetylation of treha-lose monohydroxycorynomycolate (hTMCM) promotes its transport across the inner membrane. Acetylation is mediated by the membrane acetyltransferase, TmaT, and is dependent on the pres-ence of a putative methyltransferase, MtrP. Here, we identify a third protein that is required for the acetylation and membrane ..