title: Evidence that bacterial cyanide oxygenase is a pterin-dependent hydroxylase.
abstract: The soluble cell-free fraction (150,000g high-speed supernatants [HSS]) of Pseudomonas fluorescens NCIMB 11764 contains putative cyanide oxygenase (CNO) responsible for initiating cyanide oxidation and assimilation as a nitrogenous growth substrate. CNO activity, assayed either by cyanide-dependent O(2) or NADH uptake, or by conversion of radioactive K(14)CN to (14)CO(2), was detected at micromolar concentrations (apparent half-saturation constant, 4 microM). Results demonstrating that CNO requires a protein-enriched cell fraction and a low MW redox factor (<500 Da) for which reduced biopterin could substitute are presented. The properties of CNO are consistent with those of a pterin hydroxylase.
authors.affiliation: Department of Biological Science, University of North Texas, Denton, Texas 76203-5220, USA. kunz@unt.edu
authors.forename: D A
authors.initials: DA
authors.lastname: Kunz
authors.forename: R F
authors.initials: RF
authors.lastname: Fernandez
authors.forename: P
authors.initials: P
authors.lastname: Parab
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D003486:Cyanides / Q000378:metabolism*; D006899:Mixed Function Oxygenases / Q000302:isolation & purification / Q000378:metabolism*; D008970:Molecular Weight; D010084:Oxidation-Reduction; D010105:Oxygenases / Q000378:metabolism*; D011551:Pseudomonas fluorescens / Q000201:enzymology*; D011622:Pterins / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D003486:Cyanides; D011622:Pterins; D006899:Mixed Function Oxygenases; D010105:Oxygenases; C436954:cyanide oxidase