青岛陆源排污口邻近海域异养细菌的组成与分布

Diversity and Distribution of Marine Heterotrophic Bacteria Nearby Qingdao Land-Based Drainage Discharge Outlets

中文关键词: 排污口  海洋异养细菌  16S rDNA  弧菌

英文关键词: Discharge outlet  Marine heterotrophic bacteria  16S rDNA  Vibrio sp.

中文摘要:

      对青岛近海度假区、港口区、养殖区、工业区4类排污口邻近海域异养细菌的组成与分布进行了调查研究，采用海洋异养细菌平板涂布培养法分离细菌，基于16S rDNA的扩增性DNA限制性酶切片段分析(ARDRA)进行聚类筛选并测序鉴定。结果显示，青岛排污口邻近海域可异养培养的菌株分布于变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、放线菌门(Actinobacteria)和拟杆菌门(Bacteroidetes) 4个细菌类群，变形菌门细菌数量占总测序数量的68%，其中γ-变形菌纲的数量在变形菌门中占88%；不同海域中细菌组成与分布有所不同，放线菌门和拟杆菌门的细菌种类较少且各海域分布有所不同，但γ-变形菌纲的弧菌属细菌(Vibrio sp.)在4类海域中均被发现，占总检测量的18.54%，其中溶藻胶弧菌(Vibrio alginolyticus)占弧菌总量的25%。不同海域也检测到 V. parahaemolyticus、V. harveyi、V. campbellii、V. parahaemolyticus等水产养殖业的潜在致病菌。根据16S rDNA系统进化关系和细菌门类聚类分析得到的结论推断，工业区与养殖区海域的细菌组成和分布相似度较高，推断各海域的细菌组成与排污口类型有一定相关性。

英文摘要:

      Three hundred and twelve strains of heterotrophic bacteria were isolated from the seawater of Qingdao land-based drainage discharge outlets. The sampling locations included tourist area, port area, aquaculture area and industrially affected region. Based on the analysis of 16S rDNA and Amplified Ribosomal DNA Restriction Analysis(ARDRA), these strains were clustered and identified. Four phyla including Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes were identified. Sixty-eight percent of strains belonged to Proteobacteria, and 88% of Proteobacteria were classified into Gammap¬roteobacteria. The diversity and distribution of the bacteria among each region were different, and a few of them were Actinobacteria and Bacteroidetes. Vibrio sp. was found in all four regions, and it accounted for more than 18% of strains. Twenty-five percent of Vibrio sp. was V. alginolyticus. Many pathogenic bacteria such as V. parahaemolyticus, V. harveyi, V. campbellii, and V. parahaemolyticus were found in all samples. Based on analysis of 16S rDNA and clustering, the diversity and distributions of bacteria between industrially affected region and aquaculture area were highly similar. These results suggest a close relationship between the environment and the diversity and distribution of bacteria among different regions.