基于PCR-DGGE指纹的南海海绵共附生细菌优势种群的揭示与系统发育分析

Revelation and phylogenetic analysis of the predominant bacterial community associated with sponges in the South China Sea based on PCR-DGGE fingerprints

采用PCR-DGGE指纹、克隆测序和系统发育分析技术较系统地对我国南海贪婪倔海绵(Dysidea avara)和澳大利亚厚皮海绵(Craniella australiensis)共附生的优势细菌进行了研究。研究发现变形菌门(Proteobacteria)细菌是这两种海绵中的主要优势细菌,贪婪倔海绵中的变形菌包含了α、β、γ三种类型,而澳大利亚厚皮海绵中仅有γ一种类型。两种海绵都有拟杆菌(Bacteroidetes),但是具体的种类不同。这些细菌都是第一次在海绵中被发现。澳大利亚厚皮海绵共附生的优势细菌还包括放线菌属(Actinobacterium)及厚壁菌门(Firmicutes)细菌,菌群多样性要比贪婪倔海绵的丰富。两种海绵尽管来自于同一海域但其共附生优势细菌的组成明显不同,这说明海绵共附生微生物具有宿主特异性。

The predominant bacterial community structure of Dysidea avara and Cranieila australiensis in the South China Sea were revealed by PCR- DGGE fingerprinting in the present study. With further cloning, sequencing and phylogenetic analysis, it was found that Proteobacteria predominated in these two sponges. Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria were found in Dysidea avara and only Gammaproteobacteria found in Craniella australiensis. Although Bacteroidetes were found in both sponges, they differed in the species. These bacteria were found in sponges firstly. The bacteria in Craniella australiensis show more complex diversity than that in Dysidea avara. Because compared with Dysidea avara, Craniella australiensis include Actinobacteria, Firmicutes, etc. The bacterial community diversity in these two sponges indicates that the sponge-associated bacteria are hostspecific even if the hosts are from the same marine location. DGGE fingerprint-based analysis should integrate with band cloning and sequencing, phylogenetic analysis, etc., molecular techniques to get precise results for the microbial community and diversity revelation. The research of studying sponge microbe by DGGE technique is initial work, that will accelerate the development of sponge microorganisms item.