Identification and engineering efflux transporters for improved L-homoserine production in Escherichia coli.

In this study, we provided further evidence that RhtA serves as a major L-homoserine exporter in E. coli, and obtained several RhtA beneficial mutants including A22V, P119L, and T235I that contributed to improving the L-homoserine resistance phenotypes and production efficiency in microbial chassis.