1v0s
Uninhibited form of Phospholipase D from Streptomyces sp. strain PMF
Structural highlights
FunctionEvolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAlmost all enzyme-catalysed phosphohydrolytic or phosphoryl transfer reactions proceed through a five-coordinated phosphorus transition state. This is also true for the phospholipase D superfamily of enzymes, where the active site usually is made up of two identical sequence repeats of an HKD motif, positioned around an approximate 2-fold axis, where the histidine and lysine residues are essential for catalysis. An almost complete reaction pathway has been elucidated by a series of experiments where crystals of phospholipase D from Streptomyces sp. strain PMF (PLD(PMF)) were soaked for different times with (i) a soluble poor, short-chained phospholipid substrate and (ii) with a product. The various crystal structures were determined to a resolution of 1.35-1.75 A for the different time-steps. Both substrate and product-structures were determined in order to identify the different reaction states and to examine if the reaction actually terminated on formation of phosphatidic acid (the true product of phospholipase D action) or could proceed even further. The results presented support the theory that the phospholipase D superfamily shares a common reaction mechanism, although different family members have very different substrate preferences and perform different catalytic reactions. Results also show that the reaction proceeds via a phosphohistidine intermediate and provide unambiguous identification of a catalytic water molecule, ideally positioned for apical attack on the phosphorus and consistent with an associative in-line phosphoryl transfer reaction. In one of the experiments an apparent five-coordinate phosphorus transition state is observed. The reaction mechanism of phospholipase D from Streptomyces sp. strain PMF. Snapshots along the reaction pathway reveal a pentacoordinate reaction intermediate and an unexpected final product.,Leiros I, McSweeney S, Hough E J Mol Biol. 2004 Jun 11;339(4):805-20. PMID:15165852[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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