Engineering Streptomyces tenebrarius to synthesize single component of carbamoyl tobramycin.

摘要

Aims: To engineer Streptomyces tenebrarius for producing carbamoyl tobramycin as a main component. Methods and Results: The aprH-M gene fragment (apramycin biosynthetic gene from GenBank) in S. tenebrarius Tt49 was knocked out by genetic engineering to form S. tenebrarius T106 ( Delta aprH-M). Compared to the wild-type strain, mutant strain T106 ( Delta aprH-M) no longer produced apramycin, while mainly synthesize carbamoyl tobramycin. TLC and HPLC-MS analyses indicated that the mutant strain significantly increased the production of carbamoyl tobramycin. Conclusions: The metabolic flow for the apramycin and its analogues biosynthesis was blocked by disrupting the aprH-M gene clusters. The aprH-M gene clusters might be essential for the biosynthesis of apramycin. The mutant strain T106 mainly synthesized carbamoyl tobramycin. Significance and Impact of Study: The mutant T106 mainly produces carbamoyl tobramycin without synthesizing apramycin, which will reduce cost of postextraction from fermentation products. Therefore, it has good prospects for industrial application.