Open Access2‐Hydroxyisonicotinate dehydrogenase isolated from Mycobacterium sp. INA1
Author(s) -
Schräder Thomas,
Hillebrand Cornelia,
Andreesen Jan R
Publication year - 1998
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.1574-6968.1998.tb13103.x
Subject(s) - flavoprotein , xanthine dehydrogenase , biochemistry , cofactor , cyanide , chemistry , enzyme , sulfite oxidase , formate dehydrogenase , sulfur , dehydrogenase , molybdenum cofactor , oxidase test , xanthine oxidase , stereochemistry , biology , inorganic chemistry , organic chemistry
2‐Hydroxyisonicotinate dehydrogenase from Mycobacterium sp. INA1 was purified 26‐fold to apparent homogeneity. The enzyme is involved in isonicotinate degradation by Mycobacterium sp. INA1 and catalyzes the conversion of 2‐hydroxyisonicotinate to 2,6‐dihydroxypyridine‐4‐carboxylate. The purified protein exhibited a native molecular mass of 300 kDa and subunits of 97, 31 and 17 kDa, respectively, indicating an α 2 β 2 γ 2 structure. The absorption spectrum of the homogeneous enzyme was characteristic for an iron/sulfur flavoprotein. 3.8 mol of iron, 3.7 mol of acid labile sulfur, 0.94 mol of FAD and 0.75 mol of molybdenum were determined per mol of protomer. The molybdenum cofactor was identified as molybdopterin cytosine dinucleotide. 2‐Hydroxyisonicotinate dehydrogenase was inactivated in the presence of cyanide. According to these basic properties the protein seems to belong to the class of molybdo‐iron/sulfur flavoproteins of the xanthine oxidase family.