31P NMR in vivo
Springer Online Journal Archives 1860-2000
Abstract Ethanol inhibition of glucose catabolism in Zymomonas mobilis was investigated using 31P NMR spectroscopy in vivo and of perchloric acid extracts from cell suspensions incubated with 0, 5 and 10% (w/v) ethanol. In vivo 31P NMR experiments revealed slower glucose utilization and decreased levels of nucleoside triphosphates in the presence of 10% ethanol as compared to controls. Using 31P NMR spectroscopy of perchloric acid extracts, intracellular accumulation of 3.4 mM 3-phosphoglycerate was found when 10% ethanol was present in the medium. No accumulation of this metabolite occurred in cells incubated with 0 and 5% ethanol. Enzyme assays confirmed that phosphoglycerate-mutase and enolase were inhibited 31 and 40%, respectively, in the presence of 10% ethanol in the test system. Therefore, under the conditions used the decrease in the fermentative activity of Z. mobilis at high ethanol concentrations is due to inhibition of phosphoglycerate-mutase and enolase.
Type of Medium: