Enterocytozoon hepatopenaei (EHP) is a parasite that causes hepatopancreatic microsporidiosis and is associated with shrimp growth retardation. The intestinal bacterial is an important biological barrier against pathogen invasion. In this study, we investigated the intestinal bacterial and hepatopancreas transcriptome responses of Litopenaeus vannamei to natural EHP infection. Compared with the healthy group, obvious changes in the intestinal bacterial were caused by EHP infection, with significantly increased relative abundance of Chloroflexi and decreased relative abundance of Bacteroidetes. Several genera of bacteria with putatively beneficial substance-producing characteristics were reduced in the diseased group, such as Alloprevotella, Bacillus, Bacteroides, Weissella, and Pandoraea. The hepatopancreas transcriptome revealed differentially expressed genes mainly associated with carbohydrate digestion and absorption, and some immune-related genes associated with antimicrobial processes were downregulated in contrasting accessions. Bacillus had the mostly positive correlation with gene markers; Tryp and Fer2 had positive correlation with intestinal bacteria, but APOD, FABP and HSP67 had negative correlation with them. These results revealed that EHP infection causes intestinal bacterial variation and influences the nutrition metabolism and immunity of L. vannamei.

Enterocytozoon hepatopenaei（EHP）是一种引起肝胰腺微孢子虫病的寄生虫，与虾的生长迟缓有关。肠道细菌是抵抗病原体入侵的重要生物屏障。在这项研究中，我们调查了南美白对虾对自然EHP感染的肠道细菌和肝胰腺转录组反应。与健康组相比，EHP感染引起肠道细菌发生明显变化，绿弯曲菌相对丰度明显增加，拟杆菌的相对丰度下降。在患病组中减少了具有公认有益物质产生特性的细菌的几属，如异源丙型芽孢杆菌，芽孢杆菌，拟杆菌，Weissella和Pandoraea。肝胰腺转录组显示差异表达的基因主要与碳水化合物的消化和吸收有关，而与抗菌过程有关的一些免疫相关基因在相反的种质中被下调。芽孢杆菌与基因标记物之间存在大多数正相关。Tryp和Fer2与肠道细菌呈正相关，而APOD，FABP和HSP67与它们呈负相关。这些结果表明，EHP感染会引起肠道细菌变异，并影响南美虾的营养代谢和免疫力。