Degradation of Maltose by Proliferating Cells of Desulfovibrio desulfuricans 2198

L. M. Zolotukhina¹, M. N. Davydova^1*, and E. N. Krasilnikova²

¹Kazan Institute of Biochemistry and Biophysics, Kazan Science Center, Russian Academy of Sciences, Kazan, P.O. Box 30, 420503 Russia; fax: (432) 38-7577; E-mail: davydova@sci.kcn.ru

²School of Biology, Lomonosov Moscow State University, Moscow, 119899 Russia; fax: (095) 939-4308

^* To whom correspondence should be addressed.

Received December 31, 1998; Revision received February 18, 1999

---

Desulfovibrio desulfuricans 2198 can grow on maltose-based medium only in the presence of yeast extract. The results of kinetic measurements of maltose consumption by the cells show that there is no marked difference in K_m and V_max values for this bacterium versus other carbohydrate-utilizing microorganisms. The determination of some enzymes of sugar metabolism in D. desulfuricans 2198 suggests that maltose degradation occurs by the Embden--Meyerhof pathway. The cell extract also contains glucose 6-phosphate dehydrogenase 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-¹⁴C]maltose-containing medium, a portion of the labeled carbon is incorporated into biomass. As degradation products, labeled acetate and carbon dioxide are found.

---

KEY WORDS: Desulfovibrio desulfuricans, sulfate reduction, maltose

---