ICL、ICDH、ODH和GDH酶与L-谷氨酸的合成

Effect of ICL,ICDH,ODH and GDH on L-Glutamate Production

通过对对数生长期细胞的异柠檬酸裂解酶(ICL)、异柠檬酸脱氢酶(ICDH)、α-酮戊二酸脱氢酶(ODH)和谷氨酸脱氢酶(GDH)的分析以及对细胞L-谷氨酸产生量和发酵残糖的综合分析,发现由于乙醛酸循环关键酶ICL的缺失,L-谷氨酸产生量大幅下降,说明乙醛酸循环是谷氨酸棒杆菌中的主要回补途径,L-谷氨酸合成需要乙醛酸循环。在保证乙醛酸循环回补功能的前提下,提高ICDH活性,减弱ODH活性,有利于L-谷氨酸的合成。

Investigation into relationship between L-glutamate production and enzymes isocitrate lyase（ICL）,isocitrate dehydrogenase（ICDH）,2-oxoglutarate dehydrogenase（ODH）as well as glutamate dehydrogenase（GDH） from cells in the logarithmic growth phase was carried out.The results indicated that the glyoxylic cycle was the main anaplerotic pathway and indispensable for L-glutamate production in C.glutamicum.Furthermore,it was revealed that L-glutamate production could be stimulated when ICDH activity increased and ODH activity decreased in existence of the glyoxylic anaplerotic pathway.