Characterization of a mannose-6-phosphate isomerase from Geobacillus thermodenitrificans that converts monosaccharides.
A recombinant mannose-6-phosphate isomerase from Geobacillus thermodenitrificans (GTMpi) isomerizes aldose substrates possessing hydroxyl groups oriented in the same direction at the C2 and C3 positions such as the D- and L-forms of ribose, lyxose, talose, mannose, and allose. The activity of GTMpi for D-lyxose isomerization was optimal at pH 7.0, 70 degrees C and 1 mM Co(2+). Under these conditions, the k(cat) and K(m) values were 74,300 s(-1) and 390 mM for D-lyxose and 28,800 s(-1) and 470 mM for L-ribose, respectively. The half-lives of the enzyme at 60, 65, and 70 degrees C were 388, 73, and 27 h, respectively. GTMpi catalyzed the conversion of D-lyxose to D-xylulose with a 38% conversion yield after 3 h, and converted L-ribose to L-ribulose with a 29% conversion yield.
Yeom
Soo-Jin
SJ
Department of Bioscience and Biotechnology, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, 143-701, South Korea.
Kim
Nam-Hee
NH
Yoon
Ran-Young
RY
Kwon
Hyun-Jung
HJ
Park
Chang-Su
CS
Oh
Deok-Kun
DK
D001406:Bacillaceae / Q000201:enzymology*; D003035:Cobalt / Q000494:pharmacology; D020536:Enzyme Activators / Q000494:pharmacology; D004795:Enzyme Stability; D006207:Half-Life; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008359:Mannose-6-Phosphate Isomerase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D009005:Monosaccharides / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature
D020536:Enzyme Activators; D009005:Monosaccharides; D011994:Recombinant Proteins; D003035:Cobalt; D008359:Mannose-6-Phosphate Isomerase