Progress on the construction of Streptomyces minimized genomes.

The genus Streptomyces provides a wealth of natural products with diverse structures, accounting for more than two-thirds of natural antibiotics. However, the original Streptomyces producers of desired natural products are technically challenging due to their harsh cultivation conditions, slow growth rate and intricate genetic backgrounds. Meanwhile, the metabolites of Streptomyces can also cause interference with the extraction of the target natural products. Thus, there is an urgent need to develop an ideal Streptomyces chassis with characterization of clean metabolic background, fluent genetic manipulation, and higher success rate of biosynthetic gene cluster expressions, which can largely increase yield and reduce production costs of natural products. In this review, we summarize the recent development of the chassis in Streptomyces and its important roles in the excavation and production of natural products, with focus on its potential for discovery and synthesis of natural products.