【摘要】 以提取自东海海域两种鲨鱼(尖吻鲭鲨和噬人鲨)鳃耙组织的总DNA为模板,对其真菌菌群rDNA的基因内转录间隔区ITS1序列进行了PCR扩增,扩增产物经变性梯度凝胶电泳(DGGE)分离,电泳图谱中的7条主要条带经过二次PCR扩增后进行了克隆测序。NCBI-BLAST比对及分子系统发育分析结果表明,尖吻鲭鲨鳃部真菌菌群的优势种来自四个分类单元,其中一个来自青霉属,三个来自曲霉属;噬人鲨鳃部真菌的优势种来自四个分类单元,其中一种来自青霉属、两个来自梗孢酵母属、一个来自枝顶孢属;青霉属为两种鲨鱼鳃部共同的优势菌;另外DGGE指纹图谱显示还有种类较丰富的劣势菌存在。数据库检索显示多数真菌分类单元具有较好的产生生物活性天然产物的潜力。该PCR-DGGE分析揭示鲨鱼鳃部栖生有较丰富的真菌类群,它们的代谢产物及其与宿主之间的相互作用还有待深入研究。更多还原

【Abstract】 Gill tissue DNA samples were extracted from two shark specimens from East China Sea, Isurus oxyrinchus and Carcharodon carcharias, and used as templates for PCR amplification for the sequences of internal transcribed spacer 1 in ribosomal DNA gene of the fungal communities in the gill tissue. The PCR products were subsequently separated by DGGE(denatured gradient gel electrophoresis). Then, seven main electrophoresis stripes in the spectrum were amplified by secondary PCR, cloned, and sequenced. NCBI-BLAST comparison and molecular phylogenetic analysis indicated that the dominant fungal species in the gills of I. oxyrinchus come from four taxonomical units including one from genus Penicillium and three from Aspergillus. For C. carcharias, one dominant taxonomical unit comes from Penicillium, two from Sterigmatomyces, and one from Acremonium. Penicillium is the common dominant fungal group in gills of the two shark species. In addition, the DGGE fingerprint also shows the presence of diverse minor fungal groups. Database searching suggested that most of these fungal taxonomical units have good potential in the production of natural bioactive substances. The PCR-DGGE analysis revealed that rich fungal community inhabits the two shark specimens’ gills. More investigations are demanded for understanding the metabolites and interaction with their hosts.更多还原