| Microorganisms (especially Streptomyces) are one of the main sources of agricultural antibiotics. Gene screening in early stage has found that Streptomyces cavourensis NA4 to have the potential to produce a variety of PKS and NRPS type compounds, however, only bafilomycins of PKS I type against plant pathogenic fungi were isolated. In order to burrow more antifungal guiding compounds, a genome scanning draft of S. cavourensis NA4 was obtained using Hiseq2500 high throughput sequencing technology, it was found through bioinformatic analysis and literature retrieval, strain NA4 also possessing the potential production of polycyclic tetramate macrolactam (PTM), alkylresorcinol, and valinomycin type antifungal active matter, except for producing bafilomycins. In order to activate these gene clusters, through changing the components of carbon and nitrogen sources in the medium, and adding amino acid precursors and different metal ions, and applying activity tracing as well as HPLC-UV, it was found that using pollard to replace glycerol in NM2 medium cultural conditions could activate frontalamides synthetic gene cluster of PTM. There were seven main compounds being PTM type compound, among them three possibly were new compounds. In this study, the PTM gene cluster was activated adopting culture regulation, and it provided a guidance for further separation and identification of novel PTM compounds. |
