Piscidin, Fish Antimicrobial Peptide: Structure, Classification, Properties, Mechanism, Gene Regulation and Therapeutical Importance

Antimicrobial peptides (AMPs) are short molecules produced by almost all organisms. Fish AMPs contain innate immune components as their primary immune molecules. The fish AMPs include piscidins, hepcidins, defensins, cathelicidins and histone-derived peptides. Piscidin is potent and broad-spectrum; this peptide was conserved among Acanthopterygii superorder and is therapeutically important among other AMPs. It was present mainly in the tissues of gills, muscle, head-kidney, skin and intestine of teleost. Piscidin AMP family includes piscidin, moronecidin, pleurocidin, epinecidin, gaduscidin, misgurin, dicentracin, chrysophsin and myxinidin. This review reports the structural properties of various piscidin and their mode of action as it is important to know their mechanism how the peptide involved in antimicrobial activity. In addition, the gene expression of piscidin which influenced the immune responses, their pharmaceutical importance and biological applications were described. Overall, the review explains a broad spectrum of knowledge on piscidin, its classes and types, structure, cytotoxicity, membrane permeabilization, properties and therapeutical implications.