大肠杆菌sdaA、sdaB,pgpB基因的敲除及其对磷脂酰丝氨酸合成的影响

The Effect on Phosphatidylserine Biosynthesis of Gene sdaA,sdaB,pgpB in Escherichia coli

利用Red同源重组技术敲除大肠杆菌sdaA、sdaB和pgpB基因,阻断大肠杆菌磷脂酰丝氨酸合成途径中的底物L-丝氨酸和磷酸乙醇酸的部分分解代谢,以达到提高磷脂酰丝氨酸在菌体内含量的目的。将出发菌株和重组菌株进行摇瓶发酵,发酵1 000 min后,采用高效液相色谱法分析磷脂酰丝氨酸的产量。试验结果表明sdaA、sdaB、pgpB基因敲除后,磷脂酰丝氨酸在菌体总磷脂中的含量提高了一倍多,说明通过基因工程手段改变大肠杆菌中磷脂酰丝氨酸合成的部分代谢途径,初步获得磷脂酰丝氨酸产量提高的菌株,具有较好的应用前景。

The gene sdaA, sdaB, pgpB were deleted in Escherichia coti by the technology of Red homologous recombination system, resuhingin the cut-off of part of the L-serine and PGP catabolic pathway, then the levels of phosphatidylserine （ PS ） could be elevated. To assess the effects of sdaA, sdaB, pgpB deletion on PS accumulation, both the recombinant and recipient strains were cultivated in LB-containing flasks. Then the samples were taken after 1 000 minutes and quantification of PS performed with HPLC. The results showed that the recombinant E. coli cells produced PS one fold more than the wild-type strain, suggesting the effectiveness of targeted alteration of the metabolic pathways of PS for improvement of PS production. Cost-effective large-scale production of PS should find important applications in various industrial fields.