TOBIOJ The Open Biology Journal Open Bio. J. 1874-1967 Bentham Open TOBIOJ-1-21 10.2174/1874196700801010021 Biology Isolation and Partial Characterization of an Antiviral Proteolytic Fraction from the Venom of Echis Carinatus Sochureki Borkow G. 1 * Marco D. 2 Ovadia M. 2 Cupron Inc. Hameyasdim 44, Gibton 76910, Israel, and Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv 69978, Israel Address correspondence to this author at the Cupron Inc. Chemtex, P.O. Box No. 23311, Jerusalem 91233, Israel; Tel: 972-8-546-611287; Fax: 972-8-9491254; E-mail: gadi@cupron.com 08 8 2008 2008 1 21 26 06 03 2008 07 05 2008 02 06 2008 © 2008 Borkow et al. 2008 G. Borkow

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The venom of the viper Echis carinatus sochureki suppresses the hemolytic activity of Sendai virus on human erythrocytes, when pre-incubated with the virions prior to their binding to cells. A fraction (C1), with an IC50 of 1.25 􀀁g/ml, was isolated from the venom. Fraction C1 possesses strong azocollase, azocaseinase and gelatinase activity. The proteolytic and anti-hemolytic potency of C1 depends on the period and temperature of incubation. Its antiviral activity is inhibited by Sodium-EDTA but not by PMSF. SDS PAGE of Sendai virus incubated with fraction C1 shows disappearance of several of the virion high molecular weight bands. We suggest that inhibition of the hemolytic activity of the virions is probably a result of the cleavage of viral surface proteins, such as the hemagglutinin-neuraminidase glycoprotein found on the virion envelope that mediates the absorption of the virus to cells.