Construction of SPA7074-deficient mutant of biocontrol strain Streptomyces pactum Act12 and characterization of its secondary metabolites

Abstract:

[Objective] To disrupt spa7074, which encodes a member of the TetR family transcriptional factors, in biocontrol strain Act12 and characterize the secondary metabolites in the mutant strain. [Methods] We disrupted the gene spa7074 by homologous recombination. The secondary metabolites of the mutant strain Δspa7074 and Act12 were detected by HPLC. The structure was analyzed by MS and NMR. [Results] Compared to the wild-type strain, the production of some unknown compounds in the mutant strain Δspa7074 increased obviously. We purified one of the compounds and identified as oligomycin D by MS and NMR analysis. [Conclusion] An oligomycin D-producing strain Δspa7074 was derived via genetic engineering.

Key words:biocontrol strain;Streptomyces pactum Act12;TetR family;gene disruption;oligomycin D