The effect of piscidin antimicrobial peptides on the formation of Gram‐negative bacterial biofilms

Abstract

Fish-derived antimicrobial peptides are an important part of the innate immune system due to their potent antimicrobial properties. Piscidins are a class of antimicrobial peptides first described in hybrid striped bass (Morone chrysops x Morone saxatilis) but have also been identified in many other fish species. Previous work demonstrated the broad antimicrobial activity of piscidins against Gram-negative and Gram-positive bacterial species. This study sought to determine the extent to which class I (striped bass piscidin 1, white bass piscidin 1 and striped bass/white bass piscidin 3) and class II (striped bass piscidin 4 and white bass piscidin 5) piscidins inhibit biofilm formation of different Gram-negative bacteria. In general, the class I and II piscidins demonstrate potent activity against Escherichia coli and Flavobacterium columnare biofilms. The class II piscidins showed more activity against E.coli and F.columnare isolates than did the class I piscidins. The piscidins in general were much less effective against inhibiting Aeromonas hydrophila and A.veronii biofilm growth. Only the class I piscidins showed significant growth inhibition among the Aeromonas spp. examined.