凡纳滨对虾养殖环境及肠道微生物群落特征分析

为探究凡纳滨对虾养殖过程中其肠道和养殖环境微生物群落的结构及变化,本实验采用Illumina MiSeq测序平台,基于16S rRNA基因的测序结果,对46和86 d虾龄的凡纳滨对虾肠道以及养殖水样、底泥中的微生物群落进行分析。结果显示,86 d时微生物Shannon-Wiener多样性指数显著高于46 d,水样中的Shannon-Wiener指数显著低于底泥和凡纳滨对虾肠道;有35个门、70个纲、152个目、274个科以及420个属在水样、底泥和虾肠道中均能检测到,其中虾肠道和底泥间共有菌类较水样中更多。微生物群落随养殖时间增加发生变化,46与86 d的差异性门类为放线菌门、绿菌门、丝状杆菌门、浮霉状菌门和TM6,相对丰度随时间增加而增高。水样、底泥和虾肠道中有相对固定的优势菌群,在水样、底泥和虾肠道中主要的门类均为变形菌门、拟杆菌门和放线菌门,优势纲类为α变形菌纲、β变形菌纲以及放线菌纲,除此以外,虾肠道与底泥共有的优势纲为δ变形菌纲、γ变形菌纲以及芽单胞菌纲;从目、科、属的分类水平上看,水样、底泥和虾肠道中菌类相对丰度各异,鲜有明显重叠的优势菌类,在水样、底泥和虾肠道中均为一种未...

Microbial community in Litopenaeus vannamei intestine and its aquaculture environment

To explore the microbial community structure and changes in the intestine of Litopenaeus vannamei and its aquaculture environment during the cultivation process, Illumina MiSeq high-throughput sequencing platform was used to analyze the microbial community in the gut of L. vannamei at age of 46 and 86 days, and its aquaculture water and sediments correspondingly, based on the 16S rRNA sequence. The results showed that the Shannon-Wiener diversity indexes in water samples were significantly lower than those in sediments and shrimp intestines. We detected 35 phyla, 70 classes, 152 orders, 274 families and 420 genera that existed in water, sediments and L. vannamei intestines. There were more common microbes in the intestines of L. vannamei and the sediments than those in the water. The microbial community structure of water, sediments and L. vannamei intestines changed when culturing time prolonged, the different phyla of 46 and 86 d were Actinobacteria, Chlorobi, Fibrobacteres, Planctomycates and TM6. Relative abundance increased with time. However, the dominant flora was relatively fixed. At the phylum level, Proteobacteria, Bacteroidetes, Actinobacteria were the three dominant categories in all three kinds of samples. At the class level, Alphaproteobacteria, Betaproteobacteria and Actinobacteria were the dominant categories. In addition, L. vannamei intestines and sediment had the common dominant classes of Deltaproteobacteria, Gammaproteobacteria and Gemmatimonadetes. From the classification levels of order, family and genus, the microbial community relative abundance in various samples presented differences, so that few common categories showed overlapping dominance in samples except unclassified genera, which was the most abundant in all the samples. Besides, hgcI_clade was the dominant genus in the water, Ambiguous_taxa was the predominant genus in the L. vannamei intestines and sediments. These results further explained the correlation of the microbial community structure in intestine of L. vannamei and its aquaculture environment, and also showed the differences that emerged during the culture process.