Abstract：In order to investigate composition and diversity of intestinal bacteria of common carp(Cyprinus carpio L.) reared in saline-alkaline ponds, the 16S rRNA genes were amplified from the total DNA of intestinal bacteria in common carp by PCR with bacteria-specific primers and a clone library was constructed. Positive clones were analyzed by restriction fragment length polymorphism(RFLP), and the representative clones with unique patterns were sequenced, BLAST and then constructed phylogenetic tree. A total of 28 Operational Taxonomic Units (OTUs)(GenBank accession No. JX262557~JX262584) were sequenced from 176 clones of the clone library. The clones coverage value (C=88.6%) and rarefaction analysis both showed that the clone library covered the majority intestinal bacteria. Sequence alignment showed that the most bacteria exhibited high similarity (>98%) with known bacterial 16S rRNA genes retrieved from intestinal bacteria of fish and 4 potential novel taxonomic units exhibited low similarity (<94%) with known bacterial sequence were found. Phylogenetic analysis of the 16S rRNA sequences indicated that the intestinal bacteria in common carp reared in saline-alkaline ponds fell into the following major lineages, including Alpha and Gamma subclasses of the Proteobacteria, Firmicutes, Bacteroidetes and Fusobacteria, which accounting for 89.9%, 7.9%, 1.1% and 1.1% of the total number of clones, respectively. Seventeen sequenced OTUs(158 clones) affiliated within γ-Proteobacteria were the most diverse and dominant in our library, which had 99 to 100% similarity to known bacterial sequences belonging to Aeromonas, Shewanella, and Vibrio. The dominant genus of the intestinal bacteria was Aeromonas, which accounted for 50% of the 28 valid OTUs and 86.4% of the 176 clones. Three sequenced OTUs(3 clones) belonging to α-Proteobacteria had 99% identity to known bacterial sequences, including sequences of Devosia, Afipia, and Agrobacterium. Four sequenced OTUs(14 clones), with 99% similarity to known GenBank sequences, were affiliated with Firmicutes, which were related to the genera Fusibacter, Clostridium, and unculture bacteria. Two sequenced OTUs(2 clones) were affiliated with Bacteroidetes, which had 99% similarity to known bacterial sequences belonging to Bacteroides and Flavobacterium. The remaining 2 sequenced OTUs (2 clones) had 99% similarity to known GenBank sequences of Cetobacterium and uncultured bacterium belonging to Fusobacteria. The results showed that the fish intestinal microbiota harbored some bacteria related to pathogens, probiotics, synthesis and digestion of nutrient element. This study reveals intestinal microflora of health common carp reared in saline-alkaline ponds, and the composition of intestinal bacteria of common carp reared in saline-alkaline ponds is different from that of reared in other environments. These results can provide the basis for ecological control and prevention of the disease of common carp and the assessment of water environmental condition in ponds.
黄进强1,刘哲2,王建福1,蔡原1,冯志云3. 盐碱池塘养殖鲤肠道菌群的分子分析[J]. , 2013, 21(6): 707-715.
1,zhe liu 1, 1, 1. Molecular Analysis of Intestinal Microflora in Common Carp(Cyprinus carpio L.) from Saline-alkali Ponds. , 2013, 21(6): 707-715.
