On the mechanism of xylitol-dependent inhibition of glycolysis in Streptococcus sobrinus OMZ 176. |
| |
Authors: | B Forbord H Osmundsen |
| |
Institution: | Department of Physiology and Biochemistry, Dental Faculty, University of Oslo, Norway. |
| |
Abstract: | 1. The mechanism of xylitol-dependent inhibition of glycolysis in Streptococcus sobrinus OMZ 176 was investigated in aerobically and anaerobically grown cells. 2. Glucose-stimulated glycolysis was followed polarographically, by radio-HPLC-analyses of glycolytic intermediates, by measurement of ATP generated, and spectrophotometric monitoring of extent of NAD(P)+/NADPH-status. 3. Xylitol added to suspensions of S. sobrinus inhibited O2 uptake by approximately 20%, and led to a corresponding decrease in rate of lactate formation in aerobic and anaerobic cells. 4. Xylitol also delayed the onset of the glucose-dependent rapid reduction of NAD(P)+ by approximately 1 min, although the total extent of reduction was not significantly affected compared to control cells. 5. The inhibitory effect of xylitol on glucose dependent ATP synthesis, however, was decreased by 70-80%. 6. Hence the dramatic decrease in glucose-dependent synthesis of ATP may be the direct cause of decreased bacterial growth in the presence of xylitol. 7. A mechanism explaining the observed phenomena is proposed. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|