Effect of amn gene deletion on Corynebacterium glutamicum S9114 metabolism

Abstract:

Abstract:［Objective］ To study the effect of adenosine monophosphate nucleosidase gene deletion on Corynebacterium glutamicum S9114 metabolism.［Methods］ We constructed the amn deficient strain △amn and studied its glutamate fermentation and acid tolerance.［Results］Compared with the wild type strain，biomass of △amn strain increased by 16.2% whereas glutamate production reduced by 58.8%. After 10，25 and 40 h，intracellular ATP level of △amn strain increased 3.0，3.7 and 2.2 times．The isocitrate lyase activity increased by 17.1%，4.9% and 44.5% ，the isocitrate dehydrogenase activity decreased by 76.9%，74.6% and 5.0%，and the glutamate dehydrogenase activity decreased by 42.4%，50.8% and 42.4%．At pH4.0，the survival of △amn strain dropped 64.9%．However，the intracellular ROS and protein carbonylation level showed an increase of 31.5% and 22. 5% respectively.［Conclusion］Knocking out of amn gene enhanced intracellular ATP level and biomass formation，whereas had negative effect on glutamate fermentation and acid tolerance．