Metagenoma do músculo caudal de um exemplar do camarão Penaeus vannamei infectado pelo vírus da síndrome da mancha branca

Abstract

The white leg shrimp (Penaeus vannamei) is the most cultivated species in worldwide aquaculture. The commercial cultives often occurs in high densities, leading to the selection of virulent pathogens and outbreaks. Therefore, strategies for monitoring the microbiota in cultives become necessary and, in this context, the usage of metagenomics have been suggested in aquaculture. Shotgun metagenomics can recover the genomic information of the host and its associated microbiota, including viruses, allowing to discover its taxonomic and functional composition. In this study it was performed a metagenomic analysis of shotgun sequencing data from the caudal muscle of a P. vannamei specimen infected by the shrimp white spot syndrome virus (WSSV), aiming to prospect sequences and information from the metagenome. Taxonomical and functional classifications were performed in order to obtain these respective profiles of the data. P. vannamei and WSSV were the most abundant organisms in the taxonomical classification. The functional classification was performed using MEGAN software and showed many functions related to carbohydrate, lipid and protein metabolic pathways, besides functions related to virulence (release from viral latency, integrase, “CRISPR associated helicase, cas3” and acriflavin resistance). A taxonomical classification from the BLASTx with MEGAN showed similar results to the classifications with BLASTn, reinforcing them. The BLASTn results guided the assembly of the mitochondrial genome of P. vannamei, on which a preliminary study was done to characterize its d-loop region and evaluate its barcoding potential. Also, 287 contigs were annotated for P. vannamei, which still lacks a reference genome. At last, this study revealed low taxonomic and functional diversities in the shrimp’s muscle, evidence of occurrence of potentially pathogenic nematodes, the annotation of ORFs for P. vannamei, besides the characterization of the mitochondrial d-loop of P. vannamei species.