brevinin-1-protein--rana and indolicidin

A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide microplate assay was adapted to screen for the ability of 20 host-defense peptides to inactivate herpes simplex virus type 1 and type 2. The procedure required minimal amounts of material, was reproducible, and was confirmed with standard antiviral testing techniques. In screening tests, with the exception of melittin, a highly cytotoxic and hemolytic peptide found in bee venom, the alpha-helical peptides in our test panel (magainins, cecropins, clavanins, and LL-37) caused little viral inactivation. Several beta-sheet peptides (defensins, tachyplesin, and protegrins) inactivated one or both viruses, sometimes with remarkable selectivity. Two peptides were identified as having antiviral activity against both viruses, indolicidin (a tryptophan-rich peptide from bovine neutrophils) and brevinin-1 (a peptide found in frog skin). The antiviral activity of these two peptides was confirmed with standard antiviral assays. Interestingly, the antiviral activity of brevinin-1 was maintained after reduction and carboxamidomethylation, procedures that abolished its otherwise prominent hemolytic and cytotoxic effects.

Topics: Amino Acid Sequence; Amphibian Proteins; Animals; Antimicrobial Cationic Peptides; Antiviral Agents; Cattle; Chlorocebus aethiops; Dose-Response Relationship, Drug; Erythrocytes; Hemolysis; Herpesvirus 1, Human; Herpesvirus 2, Human; Humans; Molecular Sequence Data; Peptides; Rabbits; Tumor Cells, Cultured; Vero Cells; Viral Plaque Assay