title: Functional gene-guided discovery of type II polyketides from culturable actinomycetes associated with soft coral Scleronephthya sp.
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 KS(α) (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 phylogenetically diverse culturable actinomycetes associated with the tissue of soft coral Scleronephthya sp. and the potential of coral-derived actinomycetes especially Micromonospora in producing aromatic polyketides.
authors.affiliation: 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.
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.forename: Chongsheng
authors.initials: C
authors.lastname: Peng
authors.forename: Yunyu
authors.initials: Y
authors.lastname: Zhao
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Li
mesh_terms: D039903:Actinobacteria / Q000235:genetics*; D000818:Animals; D037421:Anthozoa / Q000382:microbiology*; D001483:Base Sequence; D002681:China; D002851:Chromatography, High Pressure Liquid; D005285:Fermentation / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics*; D056726:Genetic Association Studies; D014644:Genetic Variation; D007546:Isoquinolines / Q000737:chemistry / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008847:Micromonospora / Q000235:genetics; D008969:Molecular Sequence Data; D009792:Oceans and Seas; D010802:Phylogeny; D061065:Polyketides / Q000737:chemistry / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013056:Spectrophotometry, Ultraviolet
chemical_list: D007546:Isoquinolines; D061065:Polyketides; D012336:RNA, Ribosomal, 16S; C081750:jadomycin B