title: Degradation of the metal-cyano complex tetracyanonickelate (II) by Fusarium oxysporum N-10.
abstract: A fungus with the ability to utilize a metalcyano compound, tetracyanonickelate (II) ¿K2[Ni (CN)4]; TCN¿, as its sole source of nitrogen was isolated from soil and identified as Fusarium oxysporum N-10. Both intact mycelia and cell-free extract of the strain catalyzed hydrolysis of TCN to formate and ammonia and produced formamide as an intermediate, thereby indicating that a hydratase and an amidase sequentially participated in the degradation of TCN. The enzyme catalyzing the hydration of TCN was purified approximately ten-fold from the cell-free extract of strain N-10 with a yield of 29%. The molecular mass of the active enzyme was estimated to be 160 kDa. The enzyme appears to exist as a homotetramer, each subunit having a molecular mass of 40 kDa. The enzyme also catalyzed the hydration of KCN, with a cyanide-hydrating activity 2 x 10(4) times greater than for TCN. The kinetic parameters for TCN and KCN indicated that hydratase isolated from F. oxysporum was a cyanide hydratase able to utilize a broad range of cyano compounds and nitriles as substrates.
authors.affiliation: Department of Biotechnology, Tottori University, Japan. yanase@bio.tottori-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Yanase
authors.forename: A
authors.initials: A
authors.lastname: Sakamoto
authors.forename: K
authors.initials: K
authors.lastname: Okamoto
authors.forename: K
authors.initials: K
authors.lastname: Kita
authors.forename: Y
authors.initials: Y
authors.lastname: Sato
mesh_terms: D000595:Amino Acid Sequence; D001673:Biodegradation, Environmental; D003470:Culture Media; D003486:Cyanides / Q000378:metabolism*; D005670:Fusarium / Q000145:classification / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism*; D006836:Hydro-Lyases / Q000737:chemistry / Q000378:metabolism; D007700:Kinetics; D008969:Molecular Sequence Data; D009532:Nickel / Q000378:metabolism*; D012988:Soil Microbiology
chemical_list: D003470:Culture Media; D003486:Cyanides; C047503:tetracyanonickelate; D009532:Nickel; D006836:Hydro-Lyases; C076848:cyanide hydratase