Anti-herpes effect of hemocyanin derived from the mollusk Rapana thomasiana.

The cytotoxicity and the antivirus activity of native hemocyanin, RtH, derived from the Bulgarian marine mollusk Rapana thomasiana and its structural isoform, RtH2, against HSV replication was evaluated on three HSV strains--two wt strains, TM (HSV 1) and Bja (HSV 2), and one ACVR mutant with tk gene mutation, DD (HSV 2). The experiments were performed on continuous RD 64 cells and three HSV 1 and HSV 2 strains were used, two mutants sensitive to acyclovir and one resistant mutant. Both compounds were found to be effective inhibitors of wt HSV replication.

Amino acid sequence and glycosylation of functional unit RtH2-e from Rapana thomasiana (gastropod) hemocyanin.

The complete amino acid sequence of Rapana thomasiana hemocyanin functional unit RtH2-e was determined by direct sequencing and matrix-assisted laser desorption ionization mass spectrometry of peptides obtained by cleavage with EndoLysC proteinase, chymotrypsin, and trypsin. The single-polypeptide chain of RtH2-e consists of 413 amino acid residues and contains two consensus sequences NXS/T (positions 11-19 and 127-129), potential sites for N-glycosylation. Monosaccharide analysis of RtH2-e revealed a carbohydrate content of about 1.