13c nuclear magnetic resonance studies of glucose metabolism in L-glutamic acid and L-lysine fermentation by Corynebacterium Glutamicum

Abstract

Glucose metabolism in Corynebacterium glutamicum was investigated using l3C nuclear magnetic resonance (13C NMR) spectroscopy. L-Glutamic acid and L-lysine producers were cultivated in medium containing [1-13C]- or [6-13C] glucose, and the 13C NMR spectrum of the culture filtrate was measured. In each fermentation, the ratio of the contributions of the Embden-Meyerhof pathway (EMP) and the hex-osemonophosphate pathway (HMP) (EMP/HMP) was calculated on the basis of the 13C population at each carbon in the products. The EMP/ HMP was estimated as 80/20 in glutamic acid fermentation; in contrast, it was 30-40/60-70 in lysine fermentation. These results indicate that HMP contributes much more in lysine fermentation, probably because of the greater requirement of NADPH in lysine formation from glucose. © 1991, Applied Microbiology, Molecular and Cellular Biosciences Research Foundation. All rights reserved.