Whole genome analysis unveils genetic diversity and potential virulence determinants in Vibrio parahaemolyticus associated with disease outbreak among cultured Litopenaeus vannamei (Pacific white shrimp) in India

Virulence

Tetsuya Iida¹  Toshio Kodama²  Iddya Karunasagar³  Kattapuni Suresh Prithvisagar³  Indrani Karunasagar³  Ballamoole Krishna Kumar³  Praveen Rai³ 

[1] Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University, Osaka, Japa;Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University, Osaka, Japa;Department of Bacteriology, Institute of Tropical Medicine, Nagasaki University, Nagasaki Japa;Nitte (Deemed to Be University), Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Deralakatte, Mangaluru-Karnataka, Indi;

关键词: Vibriosis;    Vibrio parahaemolyticus;    comparative genomics;    genetic diversity;    virulence;   

DOI  :  10.1080/21505594.2021.1947448

来源: Taylor & Francis

【 摘 要 】

Vibrio parahaemolyticus has caused widespread mortality in Indian shrimp aquaculture in recent years. However, there are insufficient genome data for the isolates from Indian shrimp vibriosis to analyze genetic diversity and track the acquisition of genetic features that could be involved in virulence and fitness. In this study, we have performed genome analysis of V. parahaemolyticus isolated from moribund shrimps collected from shrimp farms along coastal Karnataka, India, for better understanding of their diversity and virulence. Five newly sequenced genomes of V. parahaemolyticus along with 40 genomes retrieved from NCBI were subjected to comparative genome analysis. The sequenced genomes had an overall genome size of 5.2 Mb. MLST analysis and core genome phylogenomic analysis revealed considerable genetic diversity among the isolates obtained from the moribund shrimps. Interestingly, none of the V. parahaemolyticus isolates possessed the classical features (PirAB) of the strains associated with Acute Hepatopancreatic Necrosis Disease (AHPND). This study also revealed the presence of multiple virulence attributes, including ZOT, ACE and RTX toxins, secretion systems, and mobile genetic elements. The findings of this study provide insights into the possible transition of an environmental V. parahaemolyticus to emerge as pathogens of aquaculture species by increasing its virulence and host adaptation. Future studies focusing on continuous genomic surveillance of V. parahaemolyticus are required to study the evolution and transmission of new variants in shrimp aquaculture, as well as to design and implement biosecurity programs to prevent disease outbreaks.

【 授权许可】

CC BY