Proteomic analysis of outer membrane vesicles derived from Vibrio parahaemolyticus causing translucent post-larvae...

Area of Science:

• Aquatic animal health
• Microbiology
• Molecular biology

Background:

• Translucent post-larvae disease (TPD) is a severe shrimp aquaculture disease caused by Vibrio parahaemolyticus (VpTPD).
• Understanding VpTPD pathogenicity mechanisms is crucial for disease control.
• Outer membrane vesicles (OMVs) are bacterial vesicles involved in host-pathogen interactions, but their role in VpTPD is unclear.

Purpose of the Study:

• To investigate the role of OMVs from VpTPD (VpTPD-OMVs) in shrimp pathogenicity.
• To characterize the protein cargo of VpTPD-OMVs.
• To analyze the effects of VpTPD-OMVs on shrimp immune gene expression.

Main Methods:

• Isolation and characterization of VpTPD-OMVs using differential ultracentrifugation and electron microscopy.
• Proteomic analysis of VpTPD-OMVs using Nano-HPLC-MS/MS.
• In vitro and in vivo experiments to assess OMV uptake by shrimp hemocytes and their effects on host gene expression.

Main Results:

• VpTPD-OMVs were successfully isolated and characterized, containing 846 proteins, including virulence factors.
• VpTPD-OMVs were internalized by shrimp hemocytes.
• In vivo, VpTPD-OMVs modulated the expression of immune-related genes (TLR, Relish) and mitochondrial quality control genes (Pink1, Parkin), while downregulating stress markers (JNK) and vesicle trafficking genes (Rab6a).

Conclusions:

• VpTPD-OMVs are important carriers of virulence factors.
• VpTPD-OMVs play a significant role in modulating shrimp host gene expression.
• These findings highlight VpTPD-OMVs as key mediators of TPD pathogenicity, offering new insights into disease mechanisms.