Purification and characterization of two forms of methanol dehydrogenases from a marine methylotroph.
Two methanol dehydrogenases (MDHs), MDH1 and MDH2, were purified from a marine methylotroph, Methylophaga sp. strain 1. Both enzymes had very similar properties, including the same native molecular weight, sizes of subunits and substrate specificity. The N-terminal amino acid sequence of the alpha-subunit of MDH2 differed from that of MDH1 by having a histidine residue at a highly conserved glutamate position, but both sequences showed approximately 50% homology to the alpha-subunits of other MDHs. MDH1 had higher specific activity than MDH2 with respect to methanol and ethanol as a substrate. The two enzymes did not appear to be isoforms but that either MDH1 or MDH2 could be a mutant arising from spontaneous mutation.
Chang
Alan Kuei-Chieh
AK
Department of Biological Sciences and Research Center for Proteineous Materials, Chosun University, Gwangju 501-759, Republic of Korea.
Lim
Chae Young
CY
Kim
Si Wouk
SW
You
Ho Jin
HJ
Hahm
Kyung Soo
KS
Yoon
Seong Myeong
SM
Park
Jong Kun
JK
Lee
Jung Sup
JS
D000429:Alcohol Oxidoreductases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D000595:Amino Acid Sequence; D020563:Gammaproteobacteria / Q000201:enzymology*; D007527:Isoenzymes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D000432:Methanol / Q000378:metabolism; D008969:Molecular Sequence Data; D012623:Seawater / Q000382:microbiology*; D013379:Substrate Specificity
D007527:Isoenzymes; D000429:Alcohol Oxidoreductases; C019641:alcohol dehydrogenase (acceptor); D000432:Methanol