functional gene-guided discovery of type ii polyketides from culturable actinomycetes associated with soft coral scleronephthya sp功能性gene-guided发现多酮类化合物ii型的可培养放线菌与软珊瑚scleronephthya sp.pdfVIP

Functional Gene-Guided Discovery of Type II Polyketides from Culturable Actinomycetes Associated with Soft Coral Scleronephthya sp 1 2 2 1 Wei Sun , Chongsheng Peng , Yunyu Zhao , Zhiyong Li * 1 Marine Biotechnology Laboratory, State Key Laboratory of Microbial Metabolism School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, People’s Republic of China, 2 School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People’s Republic of China Abstract Compared with the actinomycetes in stone corals, the phylogenetic diversity of soft coral-associated culturable actinomycetes is essentially unexplored. Meanwhile, the knowledge of the natural products from coral-associated actinomycetes is very limited. In this study, thirty-two strains were isolated from the tissue of the soft coral Scleronephthya sp. in the East China Sea, which were grouped into eight genera by 16S rDNA phylogenetic analysis: Micromonospora, Gordonia, Mycobacterium, Nocardioides, Streptomyces, Cellulomonas, Dietzia and Rhodococcus. 6 Micromonospora strains and 4 Streptomyces strains were found to be with the potential for producing aromatic polyketides based on the analysis of KSa (ketoacyl-synthase) gene in the PKS II (type II polyketides synthase) gene cluster. Among the 6 Micromonospora strains, angucycline cyclase gene was amplified in 2 strains (A5-1 and A6-2), suggesting their potential in synthesizing angucyclines e.g. jadomycin. Under the guidance of functional gene prediction, one jadomycin B analogue (7b, 13-dihydro-7-O-methyl jadomycin B) was detected in the fermentation broth of Micromonospora sp. strain A5-1. This study highlights the phylogenetica