The Pathogenicity and Transcriptome Analysis of Vibrio fortis to Penaeus monodon

In this study, a strain (recorded as Y6) was isolated from the biofloc pool, its DNA was extracted for 16S rDNA sequencing, and compared in the NCBI database, and it was identified as Vibrio fortis. The V. fortis were activated and cultured, and artificially injected into V. fortis to observe the symptoms and calculate the semi-lethal concentration (LC50). K-B disk method was used to detect the sensitivity of V. fortis to a variety of antibiotic drugs. V. fortis was resistant to Ampicillin, Piperacillin, Cefazolin, Cephalothin and Cefoxitin. Highly sensitive to Polymyxin B, Tobramycin, Gentamicin, Cefepime, Cefoperazone and Streptomycin. In order to explore the molecular response mechanism of V. fortis infection in P. monodon, the hepatopancreas of P. monodon infected with V. fortis at 24hpi and 48hpi by transcriptome sequencing, and a total of 347 DEGs were obtained (214 up-regulated genes and 133 down-regulated genes). In the KEGG pathway enrichment analysis of DEGs, significant changes were found in genes and signaling pathways related to immune system and substance metabolism, including NOD-like receptor signaling pathways, Toll and Imd signaling pathway, C-type lectin receptor signaling pathway. This study initially revealed the immune response of P. monodon to V. fortis infection from the molecular level, and provided a reference for further understanding of the study and control of vibriosis of shrimp.