Purification and characterization of mannitol dehydrogenase from Aspergillus parasiticus.
Mannitol dehydrogenase, NADP specific (EC 1.1.1.138), was purified from mycelium of Aspergillus parasiticus (1-11-105 Whl). The enzyme had a molecular weight of 1.4 X 10(5) and was composed of four subunits of apparently equal size. The substrate specificity was limited to D-mannitol, D-glucitol, D-arabinitol, 1-deoxy-D-mannitol, and 1-deoxy-D-glucitol. Zinc ion was a powerful inhibitor of the enzyme, inhibition being competitive with respect to mannitol, with Ki and 1 microM. It is proposed that the stimulation of polyketide synthesis by zinc ion may be mediated in part by inhibition of mannitol dehydrogenase.
D001230:Aspergillus / Q000201:enzymology* / Q000254:growth & development; D007700:Kinetics; D046911:Macromolecular Substances; D008354:Mannitol Dehydrogenases / Q000302:isolation & purification / Q000378:metabolism*; D008970:Molecular Weight; D009994:Osmolar Concentration; D013379:Substrate Specificity; D015032:Zinc / Q000494:pharmacology
D046911:Macromolecular Substances; D008354:Mannitol Dehydrogenases; D015032:Zinc