基于16SrDNA分析的浒苔外生细菌多样性研究

为研究浙江近海浒苔Ulva spp.(Enteromorpha spp.)外生细菌多样性,采用传统的形态学和16S rDNA测序分析的方法,从舟山朱家尖、宁海国华电厂和奉化南沙3个地区分离到可培养的浒苔外生细菌及其周围海水细菌65株。根据细菌菌落特征和革兰氏染色结果等将分离到的细菌分为26种表型。16S rDNA序列测序比对发现:菌株与不动杆菌属(Acinetobacter)、交替单胞菌属(Alteromonas)、弧菌属(Vibrio)、假交替单胞菌属(Pseudoalteromonas)、微小杆菌属(Exiguobacterium)、芽孢杆菌属(Bacillus)、赤细菌属(Erythrobacter)、微球菌属(Micrococcus)、假单胞菌属(Pseudomonas)、深海杆菌属(Idiomarina)、Phaeobacter、Roseivirgaj和Silicibacter等23个属相应菌株具有较高同源性。对不同地区浒苔外生细菌进行了Shannon-Wiener多样性指数分析。研究表明:(1)宁海国华电厂的浒苔外生细菌多样性最丰富,多样性指数为93.98%;(2)浒苔外生细菌与其生活地区密切相关,其群落组成具有地域差异,其优势类群也不尽相同,但均归属于变形菌门。

Diversity of Ulva spp.(Enteromorpha spp.) epiphytic bacteria based on 16S rDNA sequences

The diversity of the epiphytic bacteria was studied based on the morphological characteristics and 16S rDNA sequence analysis, which were isolated from Ulva spp. (Enteromorpha spp.) distributed in Zhujiajian Zhoushan, Guohua power plant of Ninghai and Nansha Fenghua in China. The 65 isolated strains were grouped into 26 morphotypes, which had high similarities with strains of 23 generas such as Acinetobacter sp., Alteromonas sp., Vibrio sp., Pseudoalteromonas sp., Exiguobacterium sp., Bacillus sp., Erythrobacter sp., Micrococcus sp., Pseudomonas sp., Idiomarina sp., Phaeobacter sp., Roseivirga sp., Silicibacter sp. and so on. The results suggested that:(1) The diversity of Ulva spp. (Enteromorpha spp.) epiphytic bacteria was most abundant in Guohua power plant of Ninghai, and the Shannon-Wiener index was shown at 93.98%. (2) The Flora of Ulva spp. (Enteromorpha spp.) epiphytic bacteria was relevant with its growth and living environment. Although the community structure and dominated bacterica from different origins were various, the main species of bacteria belonged to the phylum of Proteobacteria. There were still some unidentified strains in this study, which need further investigation.