Analysis of the composition of bacterial communities in the hepatopancreas and bile of Ctenopharyngodon idellus through sequencing 16S rDNA library

Abstract:

The bacterial diversity and community composition in hepatopancreas and bile of grass carp Ctenopharyngodon idellus were determined through seqencing the 16S rDNA gene library. The bacterial spectrum of hepatopancreas included eight species of Aeromonas,six species belonging to Pseudomonas,two species from Morganella,and one species each from Vibrio and Proteus. Aeromonas and Pseudomonas were two dominant genera with 36.17% and 31.91% relative abundance of community,respectively. Strains GZ16 of Aeromonas and GZ9 of Pseudomonas were two dominant species sharing same 12.77% relative abundance. The bacterial spectrum of bile included five species of Aeromonas,three species of Pseudomonas,and one species each from Morganella and Proteus. Same as found in hepatopancreas,Aeromonas and Pseudomonas were two dominant genera,sharing 35% and 27.5% relative abundance of community,respectively. Strain DN1 of Proteus was dominant species with 25% relative abundance of community. Comparative analysis showed that 10.5% community species in the hepatopancreas shared same as that in the bile,and 20% community species in the bile shared same as that in the hepatopancreas. This means there was a specific parasitic community in hepatopancreas or bile of grass carp. The results present in this research should be helpful to further understand the unknown roles of these bacteria in the hepatopancreas and bile,also to understand coevolution mechanism between bacterial community and host grass carp.