title: Shigella apyrase--a novel variant of bacterial acid phosphatases?
abstract: A virulence-associated ATP diphosphohydrolase activity in the periplasm of Shigella, identified as apyrase, was found to be markedly similar to bacterial non-specific acid phosphatases in primary structure. When the Shigella apyrase sequence was threaded in to the recently published 3D structure of the highly similar (73%) Escherichia blattae acid phosphatase it was found to have a highly overlapping 3D structure. Our analysis, which included assays for phosphatase, haloperoxidase and catalase activities, led us to hypothesize that Shigella apyrase might belong to a new class of pyrophosphatase originating as one more variant in the family of bacterial non-specific acid phosphatases. It revealed interesting structure-function relationships and probable roles relevant to pathogenesis.
authors.affiliation: Centre for Biotechnology, Anna University, 600 025, Chennai, India.
authors.forename: M Madan
authors.initials: MM
authors.lastname: Babu
authors.forename: S
authors.initials: S
authors.lastname: Kamalakkannan
authors.forename: Yerramalli V B K
authors.initials: YV
authors.lastname: Subrahmanyam
authors.forename: Krishnan
authors.initials: K
authors.lastname: Sankaran
mesh_terms: D000595:Amino Acid Sequence; D001081:Apyrase / Q000737:chemistry* / Q000378:metabolism*; D004925:Escherichia / Q000201:enzymology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010455:Peptides; D017386:Sequence Homology, Amino Acid; D012760:Shigella / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D010455:Peptides; C011083:polyproline; D001081:Apyrase