小球藻共栖微生物种群多样性分析

Population diversity analysis of Chlorella vulgaris symbiotic microorganism

[目的]分析小球藻共栖微生物的种类和种群多样性,为小球藻养殖病害防治提供依据。[方法]从小球藻共栖生长环境中分离共栖微生物,利用限制性核酸内切酶RsaⅠ酶切共生微生物的r DNA序列,进行多态性分析,获得共栖微生物种群信息。[结果]利用纯培养的方法获得15种菌落表型特征各异的小球藻共生微生物,分成7个操作分类单元(OUT),分别是变形菌门(Proteobacteria),包括:气单胞菌属(Aeromonas)、假单胞菌属(Pseudomonas)、寡养单胞菌属(Stenotrophomonas)、肠杆菌属(Enterobacter)、泛菌属(Pantoea),厚壁菌门(Firmicutes)的锰氧化还原菌(Exiguobacterium)和芽孢杆菌属(Bacillus)。在小球藻共栖微生物中未分离到弧菌,也没有分离到真菌。[结论]小球藻共栖微生物种类多样,其中,革兰氏阴性菌占据绝对优势,革兰氏阳性菌只有芽孢杆菌属和锰氧化还原菌属,其中锰氧化还原菌是首次发现,小球藻共生菌中,很少分离到真菌,本研究中没有分离到真菌。

[ Objective] Symbiotic microbes of cultured Chlorella vulgaris and population diversity were analyzed to provide da- ta for the control of disease in culture. [ Methods] Symbiotic microbes were isolated and rDNA sequences were digested with re- striction endonucleases Rsa I for polymorphism analysis. The sequences were analyzed with bioinformatics software. [ Results] After pure culture, 15 symbiotic strains with different colony phenotype were isolated from C. vulgaris culture. The isolated strains can be divided into 7 OUT （ Operational Taxonomic Unit）. A representative strain of each OUT was sequenced. These species belong to 2 phyla and 7 genera. The two phyla are Proteobacteria, which has Aeromonas, Pseudomonas, Stenotroph- omonas, Enterobacter, and Pantoea, and Firmicutes, which has Exiguobacterium and Bacillus. No strain of fungal or vibrio was isolated here.