Further Characterization of Glycerol Dehydrogenase from Cellulomonas sp. NT3060

抄録

Glycerol dehydrogenase prepared from Cellulomonas sp. NT3060 by an improved purification procedure was characterized. The molecular weight wfas calculated to be about 390, 000 by gel filtration and about 336, 000 by the sedimentation equilibrium method. The enzymewas composed of eight identical subunits whose molecular weight was 42, 000-43, 000. The NH₂-terminal and COOH-terminal amino acids of the subunit were identified as serine and histidine, respectively. The octameric subunit model of the enzyme was confirmed by electron micrographs, which showed as octad aggregate, composed of two tetragons face to face. Studies on the initial velocity and product inhibition were consistent with an ordered Bi-Bi mechanism in which NAD⁺ is bound first to the enzyme and NADHreleased last.