Abstract: The L-serine is produced by a three-step reaction of a glycolytic intermediate 3-phosphoglycerate,2 molecules of NADH were generated in the production of L-serine from sugars by Corynebacterium glutamicum.However,no NAD + was generated in this process.Did NADH affect L-serine production and cell growth of Corynebacterium glutamicum This study aimed to investigate the effects of regulation of NADH/NAD + on Corynebacterium glutamicum SYPS-062 33a△SSAAI growth,sugar consumption and L-serine accumulation by exogenous addition of niacin and endogenous overexpression of NADH oxidase.The results showed that exogenous addition of niacin had slightly enhanced the cell growth,sugar consumption and L-serine accumulation.When NADH oxidase was overexpressed,the recombinant strain Corynebacterium glutamicum SYPS-062 33a△SSAAI-noxA was constructed.The NADH oxidase activity in the recombinant strain was 11.6 folds higher than that of the parent strain.The production of L-serine in recombinant strain was 28.93 g/L,increased by 9.0％,and the yield was 0.29 g/g sugar,increased by 7.4％.Its OD562 was 51.38,increased by 6.6％.The results indicated that the overexpression of NADH oxidase could increase the cell growth,sugar consumption and L-serine production.
2017, Vol. 43 
