Genomic assembly of AHPND causing Vibrio parahaemolyticus

Vibrio parahaemolyticus is a bacterial pathogen that when acquiring the pVA1-Type plasmid carrying the pirABvp genes become lethal to Penaeus shrimps, causing Acute Hepatopancreatic Necrosis Disease (AHPND). This disease causes significant losses in the shrimp industry across the world, with outbreaks reported in Southeast Asia, Mexico and, more recently, South America. Virulence level and mortality differences have been reported in challenges tests with V. parahaemolyticus isolates from different locations, and whether this phenomenon is caused by plasmid related elements or genomic related elements from the bacteria remains unclear. In this project, nine genomes of South American V. parahaemolyticus isolates were assembled and analyzed using a comparative genomics approach. The results of these analyses indicated that all nine isolates were Mexican-like strains. Furthermore, although all genomes were highly similar, two groups of genomes: (1) genomes BA110 and BA37P5, (2) genomes BA94C2, LH47-1, LH49 and LH53-1, could be clustered together by outstanding similarities that the members of the group presented between them with respect to the rest of the genomes. In depth analyses of these similarities were carried out at (i) whole-genome, (ii) secretion system oriented, and (iii) plasmid oriented level, and lead to the identification of relevant genomic elements to the disease that varied among the different isolates in patterns that might be insightful in the understanding of the disease.