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Crystal structure of a phosphonate monoester hydrolase from rhizobium leguminosarum: a new member of the alkaline phosphatase superfamilyCrystal structure of a phosphonate monoester hydrolase from rhizobium leguminosarum: a new member of the alkaline phosphatase superfamily
Structural highlights
Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe alkaline phosphatase superfamily comprises a large number of hydrolytic metalloenzymes such as phosphatases and sulfatases. We have characterised a new member of this superfamily, a phosphonate monoester hydrolase/phosphodiesterase from Rhizobium leguminosarum (R/PMH) both structurally and kinetically. The 1.42 A crystal structure shows structural homology to arylsulfatases with conservation of the core alpha/beta-fold, the mononuclear active site and most of the active-site residues. Sulfatases use a unique formylglycine nucleophile, formed by posttranslational modification of a cysteine/serine embedded in a signature sequence (C/S)XPXR. We provide mass spectrometric and mutational evidence that R/PMH is the first non-sulfatase enzyme shown to use a formylglycine as the catalytic nucleophile. R/PMH hydrolyses phosphonate monoesters and phosphate diesters with similar efficiency. Burst kinetics suggest that substrate hydrolysis proceeds via a double-displacement mechanism. Kinetic characterisation of active-site mutations establishes the catalytic contributions of individual residues. A mechanism for substrate hydrolysis is proposed on the basis of the kinetic data and structural comparisons with E. coli alkaline phosphatase and Pseudomonas aeruginosa arylsulfatase. R/PMH represents a further example of conservation of the overall structure and mechanism within the alkaline phosphatase superfamily. A new member of the alkaline phosphatase superfamily with a formylglycine nucleophile: structural and kinetic characterisation of a phosphonate monoester hydrolase/phosphodiesterase from Rhizobium leguminosarum.,Jonas S, van Loo B, Hyvonen M, Hollfelder F J Mol Biol. 2008 Dec 5;384(1):120-36. Epub 2008 Sep 4. PMID:18793651[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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