title: Cyclic-imide-hydrolyzing activity of D-hydantoinase from Blastobacter sp. strain A17p-4.
abstract: The cyclic-imide-hydrolyzing activity of a prokaryotic cyclic-ureide-hydrolyzing enzyme, D-hydantoinase, was investigated. The enzyme hydrolyzed cyclic imides with bulky substituents such as 2-methylsuccinimide, 2-phenylsuccinimide, phthalimide, and 3,4-pyridine dicarboximide to the corresponding half-amides. However, simple cyclic imides without substituents, which are substrates of imidase (ie.g., succinimide, glutarimide, and sulfur-containing cyclic imides such as 2,4-thiazolidinedione and rhodanine), were not hydrolyzed. The combined catalytic actions of bacterial D-hydantoinase and imidase can cover the function of a single mammalian enzyme, dihydropyrimidinase. Prokaryotic D-hydantoinase also catalyzed the dehyrative cyclization of the half-amide phthalamidic acid to the corresponding cyclic imide, phthalimide. The reversible hydrolysis of cyclic imides shown by prokaryotic D-hydantoinase suggested that, in addition to pyrimidine metabolism, it may also function in cyclic-imide metabolism.
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Japan.
authors.forename: C L
authors.initials: CL
authors.lastname: Soong
authors.forename: J
authors.initials: J
authors.lastname: Ogawa
authors.forename: M
authors.initials: M
authors.lastname: Honda
authors.forename: S
authors.initials: S
authors.lastname: Shimizu
mesh_terms: D000581:Amidohydrolases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D000595:Amino Acid Sequence; D001419:Bacteria / Q000201:enzymology*; D002413:Cations, Divalent / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007094:Imides / Q000378:metabolism*; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D012230:Rhizobiaceae / Q000201:enzymology; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D002413:Cations, Divalent; D004791:Enzyme Inhibitors; D007094:Imides; D000581:Amidohydrolases; C020047:dihydropyrimidinase