Gastrodin relieves Vibrio harveyi infection by blocking hemolysin active centers

Vibrio harveyi hemolysin (VHH) is an important virulence determinant of V. harveyi. It is an extracellular protein with phospholipase activity and plays a key role in the process of pathogen infection of the host. The key role of VHH in the virulence of V. harveyi makes it an ideal target for the design of new antiviral drugs. We found that gastrodin is a natural flavonoid with no antibacterial activity and an effective antagonist of VHH-mediated hemolysis. The compound can effectively inhibit the damage caused by V. harveyi in cell culture and animal infection models. Gastrodin can down-regulate the transcription of the vhh gene, and molecular modeling and mutation analysis show that it directly blocks the amino acid residues in the active center of the protein, thereby inhibiting its cytotoxicity. Our research results indicate that gastrodin is an effective antitoxin agent for VHH, which can be further developed into a new drug for the treatment of Vibrio infection. •Gastrodin can effectively inhibit the damage caused by V. harveyi in cell culture and animal infection models.•Gastrodin can down-regulate the transcription of the vhh gene.•Molecular modeling and mutation analysis show that gastrodin blocks the amino acid residues in hemolysis active center.