摘要
Abstract
Two recombinant strains,NC-e1 and NC-e2,were produced from the modification of Corynebacterium glutamicum C.gNCF(△ldhA∷pyc,△pqo∷gapA,△cat∷pntAB,△fasR).The former was obtained through the knockout of fadD5 by pK18mobsacB suicide plasmid,and the latter was generated through further knockout of fasB from NC-e1.Subsequently,fatty acid production was evaluated using NC-e1 and NC-e2 fermentation.As a result,NC-e1 and NC-e2 mainly produced palmitic acid,oleic acid and stearic acid.Compared with the total fatty acid yield(212.2 mg/L)from C.gNCF,NC-e1 led to 29.5％higher total fatty acid,with palmitic acid and oleic acid yield increasing by 40％and 21％,respectively.In addition,NC-e2 could generate 16.9％higher oleic acid yield than NC-e2.In other words,the oleic acid yield of NC-e2 reached 1.358 times of that of C.gNCF.In conclusion,fadD5 and fasB proved to be key genes in the fatty acid production pathway of Corynebacterium glutamicum.Knocking out fadD5 could increase the accumulation of palmitic acid and oleic acid,and additional knocking out fasB could further improve the production of oleic acid.关键词
谷氨酸棒杆菌/油酸/棕榈酸/fadD5/fasBKey words
Corynebacterium glutamicum/oleic acid/palmitic acid/fadD5/fasB分类
生物工程
