Phylogenetic Diversity Analysis And Evaluating Of Novel Glycosides Biosynthetic Potential Of Mangrove Actinomycetes

Mangrove ecosystem in interidal zones of tropical and subtropical coast harbors abundant actinomycetes. Mangrove actinomycetes have unique metabolic pathways and potential abilities of synthesizing novel metabolites during their long adaption in such strong acid, high salt and high nutrition ecosystem. Glycosyltransferase is an important later modification enzyme in secondary metabolite synthesis pathways. Cloning and characterization novel glycosyltransferase genes are of great significance in the study of secondary metabolites and the structure renovation and modification. The efficiency of microwave method uses to extract genomic DNA of mangrove actinomycetes was tested firstly.5selected strains of mangrove actinomycetes were disposed with three different microwave processing (60s,90s and120s microwave irradiation) and lysozyme method in the genomic DNA extraction. The purity and concentration of the genomic DNA were determined. According to the analysis of16S rDNA sequences of the genomic DNA extracted by three group microwave methods and enzyme method, maximum similarity of16S rDNA in each experimental strains is above99.7%. It’s concluded that the three microwave methods and enzyme method have the same effects in the DNA extraction process of the experimental strains actinomycetes. Microwave method can be used in the following fast genomic DNA extraction of a large number of mangrove actinomycetes.Two media (GAO1and ISP2medium) were used in the isolation of actinomycetes from nine Guangdong mangrove samples. According to the morphological characteristics and cultural features,136strains were obtained and divided into10groups:white spore class group, yellow class group, pink spore class group, cyan class group, ashes ash class group, green class group, blue class group, ash red purple class group, ash brown class group and golden class group..66different segmentation types were obtained after RFLP analysis. Analysis of the16S rDNA sequences showed that these strains belong to4different genera of Streptomyces, Promicromonospora, Saccharopolyspora and Nocardia. The maximum identities of12strains with the known model strains were98.1%. The maximum identity of the OAct18strains and the known pattern strain is97.3%, which means it could be identified as a novel spectes of Streptomyces.Glycosyltransferase genes, PKS-I genes and NRPS genes of the54isolated magrove actinomycetes were screened and sequenced. It turned out that7strains of the54ones possessed glycosyltransferase genes. All the7strains possessed NRPS genes, and5of the7strains possessed PKS-I genes. Homology and phylogeny analysis of these synthesis genes indicated that the7glycosyltransferase positive strains have the potential of producing novel glycosidic compounds and these strains can be fully used in the following research of the glycosyltransferase function and the combination biological synthesis of glycosidic compounds.