Diversity and composition of the bacterial community in Amphioxus feces.
Amphioxus is a typical filter feeder animal and is confronted with a complex bacterial community in the seawater of its habitat. It has evolved a strong innate immune system to cope with the external bacterial stimulation, however, the ecological system of the bacterial community in Amphioxus remains unknown. Through massive parallel 16S rRNA gene tag pyrosequencing, the investigation indicated that the composition of wild and lab-cultured Amphioxus fecal bacteria was complex with more than 85,000 sequence tags being assigned to 12/13 phyla. The bacterial diversity between the two fecal samples was similar according to OTU richness of V4 tag, Chao1 index, Shannon index and Rarefaction curves, however, the most prominent bacteria in wild feces were genera Pseudoalteromonas (gamma Proteobacteria) and Arcobacter (epsilon Proteobacteria); the highly abundant bacteria in lab-cultured feces were other groups, including Leisingera, Phaeobacter (alpha Proteobacteria), and Vibrio (gamma Proteobacteria). Such difference indicates the complex fecal bacteria with the potential for multi-stability. The bacteria of habitat with 28 assigned phyla had the higher bacterial diversity and species richness than both fecal bacteria. Shared bacteria between wild feces and its habitat reached to approximately 90% (153/169 genera) and 28% (153/548 genera), respectively. As speculative, the less diversity of both fecal bacteria compared to its habitat partly because Amphioxus lives buried and the feces will ultimately end up in the sediment. Therefore, our study comprehensively investigates the complex bacterial community of Amphioxus and provides evidence for understanding the relationship of this basal chordate with the environment.
['Pan|Minming|M|', 'Yuan|Dongjuan|D|', 'Chen|Shangwu|S|', 'Xu|Anlong|A|']
D020561:Alphaproteobacteria D000818:Animals D020640:Arcobacter D017753:Ecosystem D020565:Epsilonproteobacteria D005243:Feces D020563:Gammaproteobacteria D059014:High-Throughput Nucleotide Sequencing D064175:Lancelets D064307:Microbiota D010802:Phylogeny D031161:Pseudoalteromonas D012329:RNA, Bacterial D012336:RNA, Ribosomal, 16S
Bacterial community Feces 16S rRNA gene Environment Gut microbe