Open AccessPurification and characterization of formate oxidase from a formaldehyde‐resistant fungus
Author(s) -
Kondo Tetsuya,
Morikawa Yutaka,
Hayashi Naohiro,
Kitamoto Noriyuki
Publication year - 2002
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2002.tb11337.x
Subject(s) - formate , formaldehyde , chemistry , hydrogen peroxide , methyl formate , enzyme , molecular mass , oxidase test , enzyme assay , methanol , biochemistry , nuclear chemistry , stereochemistry , chromatography , organic chemistry , catalysis
A formate oxidase activity was found in the crude extract of a formaldehyde‐resistant fungus isolated from soil. The fungus was classified and designated as Aspergillus nomius IRI013, which could grow on a medium containing up to 0.45% formaldehyde and consumed formaldehyde completely. The specific activity of formate oxidase in the extract of the fungus grown on formaldehyde was found to be considerably higher than that in the extracts of the fungus grown on formate and methanol. Formate oxidase from the fungus grown on formaldehyde was purified to homogeneity. The enzyme had a relative molecular mass of 100 000 and was composed of two apparently identical subunits that had a relative molecular mass of 59 000. The enzyme showed the highest activity using formate as substrate. Hydrogen peroxide was formed during the oxidation of formate. The Michaelis constant for formate was 15.9 mM; highest enzyme activity was found at pH 4.5–5.0. The enzyme activity was strongly inhibited by NaN 3 , p ‐chloromercuribenzoate and HgCl 2 .