A novel type of formaldehyde-oxidizing enzyme from the membrane of Acetobacter sp. SKU 14.
Membrane-bound NADP-independent formaldehyde-oxidizing enzyme was purified to homogeneity from the membrane of Acetobacter sp. SKU 14 isolated in Thailand. The enzyme was solubilized from the membrane fraction of glycerol-grown cells with 1% Tween 20 at pH 2.85, and purified to homogeneity through the steps of column chromatographies on DEAE-Sephadex A-50 and Q-Sepharose in the presence of 0.1% Tween 20 and 0.1% Triton X-100. The enzyme purified together with a cytochrome c showed a single protein band on native-PAGE, and was dissociated into three different subunits upon SDS-PAGE with molecular masses of 78 kDa, 55 kDa, and 18 kDa. The purified enzyme was finally characterized as a quinoprotein alcohol dehydrogenase (QADH), and this is the first indication that QADH highly oxidizes formaldehyde. The substrate specificity of the enzyme was found to be broad toward aldehydes and alcohols, and alcohols, especially n-butanol, n-propanol, and ethanol, were oxidized more rapidly than formaldehyde.
Shinagawa
Emiko
E
Department of Chemical and Biological Engineering, Ube National College of Technology, Tokiwadai, Ube, Japan.
Toyama
Hirohide
H
Matsushita
Kazunobu
K
Tuitemwong
Pravate
P
Theeragool
Gunjana
G
Adachi
Osao
O
D000091:Acetobacter / Q000145:classification / Q000201:enzymology* / Q000302:isolation & purification; D000429:Alcohol Oxidoreductases / Q000302:isolation & purification / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology*; D003429:Cross Reactions; D004795:Enzyme Stability; D005557:Formaldehyde / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D011485:Protein Binding; D012995:Solubility; D013379:Substrate Specificity; D013696:Temperature; D013785:Thailand
D005557:Formaldehyde; D000429:Alcohol Oxidoreductases; C019641:alcohol dehydrogenase (acceptor)