| abstract |
A new aldehyde dehydrogenase having the physico-chemical properties:-molecular weight: 150,000 ± 6,000 or 230,000 ± 9,000; substratenspecificity:active on aldehyde compounds; cofactors:pyrroloquinoline quinonenand heme c ; optimum pH: 7.0-8.5; and inhibitors: Co 2+ , Cu 2+ , Fe 2+ , Ni 2+ , Zn 2+ ,nmonoiodoacetate and EDTA, is derived from a microorganism belonging to thengenus Gluconobacter . Said aldehyde dehydrogenase can be produced byncultivating a microorganism of the genus Gluconobacter which is capable ofnproducing an aldehyde dehydrogenase having the above properties, in annaqueous nutrient medium under aerobic conditions, disrupting the cells of thenmicroorganism and isolating and purifying the aldehyde dehydrogenase fromnthe cell-free extract of the disrupted cells of the microorganism. 2-Keto-L-gulonicnacid (2-KGA) can be produced from L-sorbosone by contacting L-sorbosonenwith (i) the aldehyde dehydrogenase in the presence of an electronnacceptor, (ii) a Gluconobacter microorganism capable of producing thenaldehyde dehydrogenase in an aqueous medium under aerobic conditions orn(iii) a cell-free extract of said microorganism, and in each case isolating thenresulting 2-KGA from the reaction mixture. |