16,17-dihydroxycyclooctatin, a new diterpene from Streptomyces sp. LZ35

Abstract

Genome sequence analysis of Streptomyces sp. LZ35 has revealed a large number of secondary metabolite pathways, including a complete gene cluster for the biosynthesis of cyclooctatin. This cluster contains four genes, cotB1-4, located in a 5-kb region. Optimization of fermentation medium for LZ35Δheng (SR107) led to the identification of cyclooctatin (1) and 16,17-dihydroxycyclooctatin (2), a new diterpene. The structures of these substances were elucidated on the basis of 1D-, 2D-NMR, and HRESIMS data. Cytotoxicity against MDA-MB-231 and A549 cell lines was also evaluated. Results demonstrated that gene cluster and pathway analysis are key to guided isolation of new natural products.