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http://purl.uniprot.org/citations/12171925http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/12171925http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/12171925http://www.w3.org/2000/01/rdf-schema#comment"The adenine phosphoribosyltransferase (APRTase) from Giardia lamblia was co-crystallized with 9-deazaadenine and sulfate or with 9-deazaadenine and Mg-phosphoribosylpyrophosphate. The complexes were solved and refined to 1.85 and 1.95 A resolution. Giardia APRTase is a symmetric homodimer with the monomers built around Rossman fold cores, an element common to all known purine phosphoribosyltransferases. The catalytic sites are capped with a small hood domain that is unique to the APRTases. These structures reveal several features relevant to the catalytic function of APRTase: 1) a non-proline cis peptide bond (Glu(61)-Ser(62)) is required to form the pyrophosphate binding site in the APRTase.9dA.MgPRPP complex but is a trans peptide bond in the absence of pyrophosphate group, as observed in the APRTase.9dA.SO4 complex; 2) a catalytic site loop is closed and fully ordered in both complexes, with Glu(100) from the catalytic loop acting as the acid/base for protonation/deprotonation of N-7 of the adenine ring; 3) the pyrophosphoryl charge is neutralized by a single Mg2+ ion and Arg(63), in contrast to the hypoxanthine-guanine phosphoribosyltransferases, which use two Mg2+ ions; and 4) the nearest structural neighbors to APRTases are the orotate phosphoribosyltransferases, suggesting different paths of evolution for adenine relative to other purine PRTases. An overlap comparison of AMP and 9-deazaadenine plus Mg-PRPP at the catalytic sites of APRTases indicated that reaction coordinate motion involves a 2.1-A excursion of the ribosyl anomeric carbon, whereas the adenine ring and the 5-phosphoryl group remained fixed. G. lamblia APRTase therefore provides another example of nucleophilic displacement by electrophile migration."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.org/dc/terms/identifier"doi:10.1074/jbc.M205596200"xsd:string
http://purl.uniprot.org/citations/12171925http://purl.org/dc/terms/identifier"doi:10.1074/jbc.m205596200"xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Almo S.C."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Almo S.C."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Shi W."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Shi W."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Wang C.C."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Wang C.C."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Schramm V.L."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Schramm V.L."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Sarver A.E."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Sarver A.E."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Tanaka K.S."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/author"Tanaka K.S."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/date"2002"xsd:gYear
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/date"2002"xsd:gYear
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/name"J. Biol. Chem."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/name"J Biol Chem"xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/pages"39981-39988"xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/pages"39981-39988"xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/title"Closed site complexes of adenine phosphoribosyltransferase from Giardia lamblia reveal a mechanism of ribosyl migration."xsd:string
http://purl.uniprot.org/citations/12171925http://purl.uniprot.org/core/title"Closed site complexes of adenine phosphoribosyltransferase from Giardia lamblia reveal a mechanism of ribosyl migration."xsd:string
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