Enhanced production of shikimic acid using a multi-gene co-expression system in Escherichia coli

Shikimic acid（SA） is the key synthetic material for the chemical synthesis of Oseltamivir, which is prescribed as the front-line treatment for serious cases of influenza. Multi-gene expression vector can be used for expressing the plurality of the genes in one plasmid, so it is widely applied to increase the yield of metabolites. In the present study, on the basis of a shikimate kinase genetic defect strain Escherichia coli BL21（?aro L/aro K, DE3）, the key enzyme genes aro G, aro B, tkt A and aro E of SA pathway were co-expressed and compared systematically by constructing a series of multi-gene expression vectors. The results showed that different gene co-expression combinations（two, three or four genes） or gene orders had different effects on the production of SA. SA production of the recombinant BL21-GBAE reached to 886.38 mg·L;, which was 17-fold（P < 0.05） of the parent strain BL21（?aro L/aro K, DE3）.