广西北部湾海域表层海水细菌多样性及其潜在生物合成基因研究

本研究选取广西北部湾3处近海海域,以其表层海水作为研究对象进行细菌多样性分析,旨在挖掘潜在抗生素生物合成的菌株.选用传统稀释涂布法和基于16S rRNA基因序列的系统发育树分析海水中可培养细菌多样性,并对其基因组DNA进行抗生素生物合成基因聚酮合酶(PKS)基因、非核糖体肽合成酶(NRPS)基因及卤化酶(Halo)基因...

Study on Biodiversity and Potential Biosynthetic Genes in Surface Seawater of Guangxi Beibu Gulf

In this study, three characteristic sea areas in Beibu Gulf of Guangxi were selected, and the surface seawater was used as the research object for bacterial diversity analysis, aiming to explore the potential antibiotic biosynthesis gene from these strains.The diversity of culturable bacteria in seawater was analyzed by traditional dilution coating method and phylogenetic analysis of 16S rRNA gene sequence.Polyketide synthase (PKS) gene, nonribosomal peptide synthetase (NRPS) gene and halogenase (Halo) gene were amplified and detected.A total of 252 strains, belonging to 4 phyla, 37 genera and 52 species, were isolated and identified.Proteobacteria was the most dominant group (accounting for 68.25% of the total number of strains), followed by Actinobacteria (17.06%), Firmicutes (8.73%) and Bacteroidetes (5.95%).At the genus level, Pseudomonas, Streptomyces, Pseudoalteromonas and Bacillus were the main dominant groups, accounting for 38.89% of the total number of strains.Among the four isolation mediums, the number and species of bacteria isolated in 2216E medium were the most (83 strains, 37 species), and the diversity index was higher.The novelty of isolated bacteria was prominent, and the highest similarity of 16S rRNA gene between 10 strains of bacteria and their related strains was less than 98.65%, so they were speculated as potential new species.In addition, at least one secondary metabolite synthesis gene was amplified from genomic DNA of 22 strains of bacteria.In summary, the culturable bacteria in the surface seawater of Guangxi Beibu Gulf are rich in diversity and outstanding in novelty, and the strains containing antibiotic biosynthesis genes deserve further chemical research on secondary metabolites.