The highly stable alcohol dehydrogenase of Thermomicrobium roseum: purification and molecular characterization.
An alcohol dehydrogenase (ADH) was purified to electrophoretic homogeneity from an extremely thermophilic bacterium, Thermomicrobium roseum. The native enzyme was found to be a homo-dimer of 43-kDa subunits. The pI of the enzyme was determined to be 6.2, while its optimum pH is 10.0. The enzyme oxidized mainly primary aliphatic alcohols and exhibited high substrate specificity towards ethanol, n-propanol and crotyl alcohol. The highest reaction rate was observed when ethanol was used as substrate and the K(m) value of the enzyme for ethanol was 24.2 mM. Pyrazole notably inhibited the enzymatic activity. The enzyme had the optimal temperature of 70 degrees C and was highly stable against high temperature.
Yoon
Suck-Young
SY
Department of Chemistry, College of Natural Sciences, Chung-Ang University, 221 Huksuk-dong, Dongjak-ku, Seoul 156-756, South Korea.
Noh
Hyang-Soon
HS
Kim
Eun-Ho
EH
Kong
Kwang-Hoon
KH
D000426:Alcohol Dehydrogenase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D000438:Alcohols / Q000378:metabolism; D000595:Amino Acid Sequence; D001419:Bacteria / Q000201:enzymology* / Q000235:genetics; D002384:Catalysis; D002846:Chromatography, Affinity; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D021122:Protein Subunits; D013379:Substrate Specificity; D013696:Temperature
D000438:Alcohols; D021122:Protein Subunits; D000426:Alcohol Dehydrogenase