Antiviral Activity of a Turbot (Scophthalmus maximus) NK-Lysin Peptide by Inhibition of Low-pH Virus-Induced Membrane Fusion

• Published in: Marine Drugs
• Main Authors: Alberto Falco, Regla María Medina-Gali, José Antonio Poveda, Melissa Bello-Perez, Beatriz Novoa, José Antonio Encinar
• Format: Text
• Language: English
• Published: Multidisciplinary Digital Publishing Institute 2019
• Subjects: NK-lysin; Nkl 71–100; phospholipid vesicles; aggregation; leakage; phosphatidylserine; antiviral; viral fusion; SVCV; Scophthalmus maximus; Turbot
• Online Access: https://doi.org/10.3390/md17020087

Global health is under attack by increasingly-frequent pandemics of viral origin. Antimicrobial peptides are a valuable tool to combat pathogenic microorganisms. Previous studies from our group have shown that the membrane-lytic region of turbot (Scophthalmus maximus) NK-lysine short peptide (Nkl71–100) exerts an anti-protozoal activity, probably due to membrane rupture. In addition, NK-lysine protein is highly expressed in zebrafish in response to viral infections. In this work several biophysical methods, such as vesicle aggregation, leakage and fluorescence anisotropy, are employed to investigate the interaction of Nkl71–100 with different glycerophospholipid vesicles. At acidic pH, Nkl71–100 preferably interacts with phosphatidylserine (PS), disrupts PS membranes, and allows the content leakage from vesicles. Furthermore, Nkl71–100 exerts strong antiviral activity against spring viremia of carp virus (SVCV) by inhibiting not only the binding of viral particles to host cells, but also the fusion of virus and cell membranes, which requires a low pH context. Such antiviral activity seems to be related to the important role that PS plays in these steps of the replication cycle of SVCV, a feature that is shared by other families of virus-comprising members with health and veterinary relevance. Consequently, Nkl71–100 is shown as a promising broad-spectrum antiviral candidate.