Degradation of maltose by proliferating cells of Desulfovibrio desulfuricans 2198

Desulfovibrio desulfuricans 2198 can grow on maltose-based medium only in t he presence of yeast extract. The results of kinetic measurements of maltos e consumption by the cells show that there is no marked difference in K-m a nd V-max values for this bacterium versus other carbohydrate-utilizing micr oorganisms. The determination of some enzymes of sugar metabolism in D. des ulfuricans 2198 suggests that maltose degradation occurs by the Embden-Meye rhof pathway. The cell extract also contains glucose 6-phosphate dehydrogen ase and 6-phosphogluconate dehydrogenase. 2-Keto-3-deoxy-6-phosphogluconate aldolase, the key enzyme of the Entner-Doudoroff pathway, is not found in D, desulfuricans 2198. In the bacterium grown on [U-C-14]maltose-containing medium, a portion of the labeled carbon is incorporated into biomass. As d egradation products, labeled acetate and carbon dioxide are found.