title: Degradation of 2-ketoarginine by guanidinobutyrase in arginine aminotransferase pathway of Brevibacterium helvolum.
abstract: Guanidinobutyrase (EC 3.5.3.7) involved in the arginine oxygenase pathway of Brevibacterium helvolum IFO 12073 was found to catalyze also the hydrolysis of 2-ketoarginine (2-keto-5-guanidinovalerate) to 2-ketoornithine (2-keto-5-aminovalerate) and urea, the second step of the arginine aminotransferase pathway. No other enzyme that degraded 2-ketoarginine was found in cells grown on L-arginine. The enzyme hydrolyzed 2-ketoarginine with a relative rate of about 0.7% of that toward 4-guanidinobutyrate. The Km for 2-ketoarginine was 33 mM.
authors.affiliation: Department of Bioscience and Biotechnology, Shinshu University, Nagano, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yorifuji
authors.forename: M
authors.initials: M
authors.lastname: Kaneoke
authors.forename: T
authors.initials: T
authors.lastname: Okazaki
authors.forename: E
authors.initials: E
authors.lastname: Shimizu
mesh_terms: D001120:Arginine / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000378:metabolism; D001951:Brevibacterium / Q000201:enzymology*; D002848:Chromatography, DEAE-Cellulose; D007700:Kinetics; D000637:Transaminases / Q000302:isolation & purification / Q000378:metabolism*; D014512:Ureohydrolases / Q000378:metabolism*
chemical_list: C093466:2-ketoarginine; D001120:Arginine; D000637:Transaminases; D014512:Ureohydrolases; C020835:guanidinobutyrase