Incorporation of 13C glucose into nicotinamide in E. coli and in S. cerevisiae

The mode of incorporation into nicotinamide of label from 13 C-labeled samples of D-glucose, in Escherichia coli and Saccharomyces cerevisiae, was determined by means of 13 C NMR spectroscopy. The results, which confirm and extend early studies with radioactive tracers, permit a definitive choice to be made between alternative biogenetic proposals.Key words: nicotinic acid, nicotinamide, biosynthesis, glucose incorporation, 13 C NMR.