Differential expression of pathogenic factors pirA and pirB from Vibrio parahaemolyticus causing acute hepatopancreatic necrosis disease at nucleic acid and protein levels: implications for pathogen detection

2026-02-26T13:52:43+00:00

Litopenaeus vannamei is one of the most economically valuable aquaculture species. In recent years, the shrimp industry has experienced considerable economic losses due to various diseases such as acute hepatopancreatic necrosis disease (AHPND). AHPND is a disease caused by certain strain of Vibrio parahaemolyticus carrying a specific plasmid pVA1. The pVA1 plasmid contains the pirA and pirB genes, which encode the main virulence factors of AHPND. In light of the dearth of effective treatment options, the development of expeditious, precise, and effective methodologies for detecting AHPND pathogens is imperative to prevent the onset of disease in shrimp farming. However, current nucleic acid based and antibody-based detection methods sometimes produce false positive results, affecting the reliability of diagnosis. This study aims to make a comparison of the content of the pirA and pirB virulence factors at the DNA, RNA, and protein levels in order to investigate whether there is a corresponding relationship between the pathogenic factors of AHPND at the nucleic acid and protein levels, which will provide a foundation for the selection of pathogen detection methods for shrimp. At the mRNA level, the expression level of pirA is significantly higher than that of pirB. Conversely, at the protein level, the expression level of PirB protein is much higher than that of PirA protein, indicating that the results of the two different detection methods are contradictory. [cut for word limits]

Identification and characterization of a pathogenic Vibrio parahaemolyticus causing translucent post-larvae disease in Penaeus vannamei

2026-02-26T14:05:13+00:00

Penaeus vannamei is an important aquaculture species, but disease outbreaks posed a serious threat to the sustainable development of shrimp farming. In recent years, a fatal disease known as translucent post-larvae disease (TPD) has emerged in many farms, characterized by the vacuolization of the hepatopancreas and the pallor or colorlessness of the intestine. In this study, we obtained a strain of Vibrio parahaemolyticus, named H1, that could cause TPD in both juvenile and adult shrimps. V. parahaemolyticus H1 could cause gradual atrophy of the hepatopancreas, deepening of the intracellular material color, and eventually complete vacuolization. Antibiotic susceptibility tests revealed that V. parahaemolyticus H1 was resistant to chloramphenicol, ceftriaxone, and sulfamethoxazole trimethoprim, but exhibited resistance to tetracycline. The 2b-RAD-M analysis showed that V. parahaemolyticus H1 could disrupt the shrimp intestinal microbiota and lead to a loss of resistance to environmental bacteria. These results identified a pathogenic V. parahaemolyticus causing TPD from P. vannamei.

Invertebrate Survival Journal

Differential expression of pathogenic factors pirA and pirB from Vibrio parahaemolyticus causing acute hepatopancreatic necrosis disease at nucleic acid and protein levels: implications for pathogen detection

Identification and characterization of a pathogenic Vibrio parahaemolyticus causing translucent post-larvae disease in Penaeus vannamei