| 1. |
Tamura T,
Kasai H,
( 2000 ) Intrageneric relationships among Micromonospora species deduced from gyrB-based phylogeny and DNA relatedness. PMID : 10826795 : DOI : 10.1099/00207713-50-1-127 DOI : 10.1099/00207713-50-1-127 Abstract >>
The phylogenetic structure of genus Micromonospora within actinomycetes was examined by analysing the gyrB sequences of 15 validly described species and four subspecies. All but one of the Micromonospora strains formed a tight cluster, as had previously been demonstrated by a 16S rDNA-based phylogenetic analysis. However, the intrageneric relationships deduced from the gyrB-based phylogeny were different from those based on their 16S rDNA sequences. To examine which phylogeny would be more relevant for classifying genus Micromonospora, DNA-DNA hybridization experiments were performed. The gyrB-based classification agrees with the results of the DNA-DNA hybridization studies, indicating that this classification method is useful for analysing the phylogenetic relationships of high G+C Gram-positive bacteria at the level of the genomic species. Genus Micromonospora was reclassified into the following 14 species: Micromonospora echinospora, Micromonospora pallida, Micromonospora nigra, Micromonospora purpureochromogenes, Micromonospora aurantiaca, Micromonospora carbonacea, Micromonospora chalcea, Micromonospora chersina, Micromonospora coerulea, Micromonospora gallica, Micromonospora halophytica, Micromonospora inositola, Micromonospora olivasterospora and Micromonospora rosaria.
|
2. |
( 2012 ) Functional gene-guided discovery of type II polyketides from culturable actinomycetes associated with soft coral Scleronephthya sp. PMID : 22880121 : DOI : 10.1371/journal.pone.0042847 PMC : PMC3413676 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(�\) (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.
|