title: A helical lid converts a sulfotransferase to a dehydratase.
abstract: We report here the crystal structure of retinol dehydratase, an enzyme that catalyzes the synthesis of anhydroretinol. The enzyme is a member of the sulfotransferase superfamily and its crystal structure reveals the insertion of a helical lid into a canonical sulfotransferase fold. Site-directed mutations demonstrate that this inserted lid is necessary for anhydroretinol production but not for sulfonation; thus, insertion of a helical lid can convert a sulfotransferase into a dehydratase.
authors.affiliation: Biochemistry Department, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA.
authors.forename: S
authors.initials: S
authors.lastname: Pakhomova
authors.forename: M
authors.initials: M
authors.lastname: Kobayashi
authors.forename: J
authors.initials: J
authors.lastname: Buck
authors.forename: M E
authors.initials: ME
authors.lastname: Newcomer
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution / Q000235:genetics; D000818:Animals; D001547:Benzaldehydes / Q000378:metabolism; D001665:Binding Sites; D018360:Crystallography, X-Ray; D006836:Hydro-Lyases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D017433:Protein Structure, Secondary; D016415:Sequence Alignment; D013329:Structure-Activity Relationship; D013431:Sulfates / Q000378:metabolism; D015238:Sulfotransferases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D014801:Vitamin A / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology
chemical_list: D001547:Benzaldehydes; D013431:Sulfates; D014801:Vitamin A; C031469:anhydrovitamin A; C100058:vanillin; D015238:Sulfotransferases; D006836:Hydro-Lyases; C100603:retinol dehydratase