5w95

Publication Abstract from PubMed

The Mycobacterium tuberculosis (Mtb) rv3802c gene encodes an essential enzyme with thioesterase and phospholipase A activity. Overexpression of Rv3802 orthologs in Mycobacterium smegmatis and Corynebacterium glutamicum increases mycolate content and decreases glycerophospholipids. While a role in modulating the lipid composition of the unique mycomembrane has been proposed, the true biological function of Rv3802 remains uncertain. In this study, we present the first Mtb Rv3802 X-ray crystal structure, solved to 1.7 A resolution. On the basis of the binding of polyethylene glycol (PEG) molecules to Rv3802, we identified its lipid-binding site and the structural basis for phosphatidyl-based substrate binding and phospholipase A activity. We found that movement of the alpha8 helix affords lipid binding and is required for catalytic turnover through covalent tethering. We gained insights into the mechanism of acyl hydrolysis by observing differing arrangements of PEG and water molecules within the active site. This study provides structural insights on biological function and facilitates future structure-based drug design toward Rv3802.

Structural basis for lipid binding and mechanism of the Mycobacterium tuberculosis Rv3802 phospholipase.,Goins CM, Schreidah CM, Dajnowicz S, Ronning DR J Biol Chem. 2017 Dec 15. pii: RA117.000240. doi: 10.1074/jbc.RA117.000240. PMID:29247008^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.