Structural highlights
Function
O27985_ARCFU A9WSF5_RENSM Catalyzes the conjugation of the 1'-hydroxyl group of D-myo-inositol-3-phosphate (also named L-myo-inositol-1-phosphate) with a lipid tail of cytidine diphosphate diacylglycerol (CDP-DAG), forming phosphatidylinositol phosphate (PIP) and CMP. PIP is a precursor of phosphatidylinositol (PI) which is an essential lipid required for cell wall formation.[HAMAP-Rule:MF_02241]
Publication Abstract from PubMed
Phosphatidylinositol is critical for intracellular signalling and anchoring of carbohydrates and proteins to outer cellular membranes. The defining step in phosphatidylinositol biosynthesis is catalysed by CDP-alcohol phosphotransferases, transmembrane enzymes that use CDP-diacylglycerol as donor substrate for this reaction, and either inositol in eukaryotes or inositol phosphate in prokaryotes as the acceptor alcohol. Here we report the structures of a related enzyme, the phosphatidylinositol-phosphate synthase from Renibacterium salmoninarum, with and without bound CDP-diacylglycerol to 3.6 and 2.5 A resolution, respectively. These structures reveal the location of the acceptor site, and the molecular determinants of substrate specificity and catalysis. Functional characterization of the 40%-identical ortholog from Mycobacterium tuberculosis, a potential target for the development of novel anti-tuberculosis drugs, supports the proposed mechanism of substrate binding and catalysis. This work therefore provides a structural and functional framework to understand the mechanism of phosphatidylinositol-phosphate biosynthesis.
Structural basis for phosphatidylinositol-phosphate biosynthesis.,Clarke OB, Tomasek D, Jorge CD, Dufrisne MB, Kim M, Banerjee S, Rajashankar KR, Shapiro L, Hendrickson WA, Santos H, Mancia F Nat Commun. 2015 Oct 16;6:8505. doi: 10.1038/ncomms9505. PMID:26510127[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Clarke OB, Tomasek D, Jorge CD, Dufrisne MB, Kim M, Banerjee S, Rajashankar KR, Shapiro L, Hendrickson WA, Santos H, Mancia F. Structural basis for phosphatidylinositol-phosphate biosynthesis. Nat Commun. 2015 Oct 16;6:8505. doi: 10.1038/ncomms9505. PMID:26510127 doi:http://dx.doi.org/10.1038/ncomms9505
