应用高通量测序技术分析大菱鲆幼鱼肠道及其养殖环境的微生物群落结构

采用基于Illumina测序平台的高通量测序技术,对大菱鲆(Scophthalmus maximus)幼鱼肠道及其养殖水体、生物饵料中细菌种类及丰度进行研究。测序结果显示,养殖水体、生物饵料和大菱鲆幼鱼肠道等19个样品共获得有效序列547621条,可聚类于3771个可分类操作单元(OTUs),归属于养殖水体、生物饵料、健康幼鱼和发病幼鱼的操作分类单元(OTU)个数分别为3038、1090、87和777,其中,健康幼鱼与生物饵料、健康幼鱼与养殖水体特有的OTU个数分别为57和0,发病幼鱼与生物饵料、发病幼鱼与养殖水体特有的OTU个数分别为481和31。表明幼鱼肠道微生物多样性与生物饵料密切相关。根据细菌注释结果,拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和变形菌门(Proteobacteria)在大菱鲆幼鱼肠道中占优势地位,其中,健康幼鱼肠道微生物共聚类为8个门,发病幼鱼的肠道微生物可聚类为19个门。与健康幼鱼相比,发病幼鱼肠道门水平上的3种主要优势菌群落结构出现失衡。此外,对各样品中丰度最高的100位OTU分析显示,幼鱼肠道优势菌种类与生物饵料中的优势菌种类密切相关,而每个发病幼鱼肠道优势菌种类具有一定的独立性。本研究旨在为大菱鲆健康养殖和微生态调控提供实验依据。

Turbot (Scophthalmus maximus) Biodiversity Assessment Using High-Throughput Illumina Sequencing to Analyze Juvenile Turbot Intestines and Their Bacterial Cultures

In order to study the effects of environmental factors on the intestinal flora structure of turbot (Scophthamus maximus), we used high-throughput sequencing to explore the bacterial community structure and diversity in juvenile turbot intestines, the culture environment, and biological baits. The results showed that 547621 effective sequences were detected in nineteen samples, and they could be classified into 3771 operational taxonomic units (OTUs), among which 3038, 1090, 87, and 777 originated from the aquaculture water, the biological baits, healthy juvenile turbot intestine, and diseased juvenile fish intestine, respectively. There were 57 OTUs shared between the healthy juvenile turbot intestine and the biological baits, 0 OTU shared between the healthy juvenile turbot intestine and aquaculture water, 481 OTUs shared between the diseased juvenile fish intestine and the biological baits, 31 OTUs shared between the diseased juvenile fish intestine and the aquaculture water. The effect of biological bait on microbial diversity of intestinal tract of juvenile fish was much greater than that of environment. In total, the predominant phyla in the turbot intestine were Bacteroidetes, Firmicutes, and Proteobacteria. The intestinal microflora of healthy juvenile turbot can be clustered into 8 phyla, and the intestinal microflora of the diseased juvenile fish could be clustered into 19 phyla. Compared with the healthy juveniles, the community structure of the predominant phyla was imbalanced at the intestinal level of the diseased juvenile fish. Furthermore, analysis of the 100 most abundant bacterial OTUs in the different samples revealed that the species dominant in the intestinal bacteria of juvenile fish was closely related to the dominant species in the biological baits. Meanwhile, the intestinal dominant bacteria species of each diseased juvenile are different. This study provided the basis for healthy culture and micro-ecological regulation of turbot.