Antimicrobial peptide hepcidin contributes to host defense of Centropristis striata against Vibrio harveyi challenge

Hepcidins are small cysteine-rich antimicrobial peptides that play a vital role in immunity against pathogen invasion.Here,a hepcidin(Cshep) from Centropristis striata was described,which is considered as a valuable aquaculture marine species in China.The open reading frame consisted of 273 bp.Eight conserved cysteine residues were identified.Phylogenetic analysis showed that Cshep had a relatively close relationship with the hepcidin from Epinephelus moara.Quantitative real-time PCR analysis demonstrated that Cshep was highly expressed in liver and significantly up-regulated when challenged with Vibrio harveyi.In addition,the synthetic Cshep peptide had a high antimicrobial activity against V.harveyi,but low against other pathogenic bacteria tested in this study.The killing kinetics analysis revealed that Cshep had a fast bactericidal effect on V.harveyi.These results suggested that Cshep may be involved in the immune response of C.striata against V.harveyi infection.