虾肝肠胞虫感染对脊尾白虾肠道菌群的影响

Effect of Enterocytozoon hepatopenaei Infection on the Intestinal Microflora of Exopalaemon carinicauda

中文关键词: 虾肝肠胞虫  脊尾白虾  肠道菌群多样性  功能预测

英文关键词: Enterocytozoon hepatopenaei  Exopalaemon carinicauda  Intestinal microflora diversity  Function prediction

中文摘要:

      为探究虾肝肠胞虫(Enterocytozoon hepatopenaei, EHP)感染对脊尾白虾(Exopalaemon carinicauda)肠道菌群的影响，本研究基于16S rRNA基因的测序结果，对感染EHP的脊尾白虾肠道菌群进行了分析。结果显示，感染虾与健康虾肠道菌群差异较大，且其肠道菌群结构多样性显著低于健康虾。研究发现，病虾中归属于变形菌门(Proteobacteria)的脱硫弧菌科(Desulfovibrionaceae)、弧菌科(Vibrionaceae)、未分类蓝细菌科(unidentified Cyanobacteria)、支原体科(Mycoplasmataceae)和未分类α变形菌科(unidentified Alphaproteobacteria)为优势菌，而归属于厚壁菌门(Firmicutes)的乳杆菌科(Lactobacillaceae)、双歧杆菌科(Bifidobacteriaceae)、芽孢杆菌科(Bacillaceae)及噬几丁质杆菌科(Chitinophagaceae)细菌在健康虾中占据优势地位。EHP侵蚀导致感染虾肠道内潜在致病菌显著增加(P<0.05)，增加了其他疾病的易感性。此外，通过Tax4Fun功能预测，发现感染虾肠道菌群主要用于新陈代谢，从而抵抗EHP侵染，维持机体正常功能；健康虾肠道菌群则多用于个体生长与环境信息处理，进而保证生长与存活。本研究从虾肠道菌群结构方面入手，进一步探究了EHP感染对脊尾白虾肠道菌群的影响，以期为EHP的防治提供帮助。

英文摘要:

      Enterocytozoon hepatopenaei (EHP) is a highly infectious intracellular parasite that primarily parasitizes the hepatopancreas, intestine, and muscle of shrimp. It can reproduce by consuming ATP from the host cells, resulting in growth retardation or even growth cessation of the host and increasing individual differences within a population. In recent years, we discovered EHP infection in the breeding process of Exopalaemon carinicauda culture, which has caused losses to the E. carinicauda culture industry. Intestinal microorganisms, which play a very important role in the growth and development of shrimp, can regulate nutritional metabolism, resist pathogen infection, and also have an important impact on the host immune function. Therefore, it is helpful to clarify the pathogenesis of EHP by exploring the differences and functions of the intestinal microflora between healthy and diseased shrimp. To screen potential probiotics for inhibiting or slowing down the spread of EHP, this study analyzed the intestinal microflora structure of shrimp based on 16s rRNA gene sequencing, and further explored the effect of EHP infection on the intestinal microflora of E. carinicauda. The results showed that the intestinal microflora of infected shrimp was significantly different from that of healthy individuals, and the structural diversity of the intestinal microflora was significantly lower than that of the healthy shrimp. Proteobacteria, including Desulfovibrionaceae, Vibrionaceae, unidentified Cyanobacteria, Mycoplasmataceae, and unidentified Alphaproteobacteria were the dominant bacteria in diseased shrimp, whereas Firmicutes including Lactobacillaceae, Bifidobacteria, Bacillaceae, and Chitinophagaceae were dominant in healthy shrimp. Infection with EHP significantly increased the potential pathogenic bacteria level in the intestines of the infected shrimp (P<0.05), and increased their susceptibility to other diseases. In addition, through the Tax4Fun function prediction, we found that the primary function of the intestinal microflora in infected shrimp was metabolism to resist EHP infection, whereas the intestinal microflora of healthy shrimp was primarily involved in individual growth and environmental information processing to ensure growth and survival.