Halomonas is capable of synthesizing organic compatible solutes ectoine in response to high osmotic pressure. To reveal the possibility of heterologous co-expression of ectoine biosynthesis genes, intracellular ectoine in Halomonas sp. QHL1 strain was determined by HPLC under different salt gradients. The entire ect ABC gene cluster for ectoine synthesis was cloned using genome walking and expressed in the heterologous recombinant E. coli BL21. The results showed that the concentration of ectoine accumulate...