Cloning and heterologous expression of sansanmycin biosynthetic gene cluster in Streptomyces coelicolor

Sansanmycins (SSs), produced by Streptomyces sp. SS, belong to uridyl peptide antibiotics which exhibit a good inhibitory effect on Mycobacterium tuberculosis and Pseudomonas aeruginosa. They share a unique chemical scaffold with a 4',5'-enamide-3'-deoxyuridine attached to DABA (N-methyl-2,3-diaminobutyryl) which was located in the peptide chain through peptide bond. In order to study the function of related genes and to employ synthetic biology to gain new SS derivatives, we obtained a complete SS biosynthetic gene cluster and heterologously expressed it in Streptomyces coelicolor M1146, M1152 and M1154. Fermentation broth of the recombinant strains were detected using HPLC and HPLC-MS/MS, and the result showed that SS-A was successfully produced in the three strains, and its production level in S. coelicolor M1154 was similar to the original wild type strain. In addition, a potential SS analogue named as SS-1154 was discovered from the fermentation broth of S. coelicolor M1154.