ISJ 10: 120-127, 2013 ISSN 1824-307X

REVIEW

Antiviral activity of hemocyanins

P Dolashka1, W Voelter2

1Institute of Organic Chemistry with Centre of Phytochemistry, BAS, Sofia, Bulgaria 2Interfacultary Institute of Biochemistry, University of Tϋbingen, Hoppe-Seyler-Strasse 4, D-72076 Tϋbingen, Germany.

Accepted October 11, 2013

Abstract Hemocyanins are giant biological macromolecules acting as oxygen-transporting glycoproteins. Most of them are respiratory proteins of arthropods and mollusks, but besides they also exhibit protecting effects against bacterial, fungal and viral invasions. As discovered by 2-DGE proteomics analyses, several proteins including hemocyanins of hemocytes from virus-infected arthropods increased upon infection, confirming hemocyanin’s role as part of the organism’s defence system. Based on the structural analyses of molluscan Hcs it is suggested that the chains of the glycoproteins seem to interact with surface-exposed amino acid or carbohydrate residues of the viruses through van der Waals interactions.

Key Words: functional units; hemocyanin; mollusks; arthropods; viruses

Introduction

The persistence of the virus in the organism and arthropodan Hcs, contain copper-containing leads to the development of lymphoproliferative active sites in which the Cu(I,I) is oxidized to the disease, the formation of various carcinomas and to Cu(II,II) state, thus accounting for their distinctive the affection of the peripheral and central nervous deep blue color. The biosinthesis of hemocyanins system. Antiviral drugs may be divided into acyclic from e.g. (CcH) takes nucleoside analogues (aciclovir, ganciclovir, place in the hepatopancreas (Manubens et al., penciclovir), acyclic nucleotide analogues (cidofovir 2010) but Megathura crenulata’s Hcs originate from and adefovir), and substances of natural origin (De rhogocytes (Martin et al., 2011). Clercq, 2004). Most of the submitted drugs are Investigations on several molluscan potent inhibitors of viral reproduction, but not all of hemocyanins, e.g. from Haliotis tuberculata (HtH, them are promising for clinical application, since Abalon) (Markl et al., 2001); lucorum (HlH, they are very different in terms of toxicity. garden ), Rapana venosa (RvH, Black sea Recently it was found that hemocyanins (Hcs), murex) (Dolashka-Angelova et al., 2003, 2009, the oxygen-transporting glycoproteins of many 2011; Iliev et al., 2008) or C. concholepas (CCH, arthropods and mollusks, could be also potential Loco) from the Pacific Chilean coast (Moltedo et al., inhibitors of some virus infections (Chongsatja et al., 2006, Arancibia et al., 2012) demonstrated their 2007; Flegel et al., 2011). These giant glycoproteins remarkable immunostimulatory properties in which differ in molecular mass, structure, experimental model and clinical studies. carbohydrate content, and monosaccharide Moreover, hemocyanins have been extensively composition have recently received increasing used as carriers to generate antibodies against interest due to their significant immunostimulatory, diverse hapten molecules and peptides to induce antitumor, and antiviral properties (Dolashka- antigen-specific CD8+ and CD4+ T cell responses Angelova et al., 2009; Dolashka et al., 2010; Mičetić (Minozzi et al., 2007; Arancibia et al., 2012). et al., 2010; De Smet et al., 2011; Rehm et al., Recently, a vaccine potential of Oncomelania 2012; Markl et al., 2013). Both , molluscan hupensis Hc against Schistosoma Japonicum ______parasite was also established (Guo et al., 2011).

Probably, due to their high carbohydrate Corresponding author: Pavlina Dolashka content and specific monosaccharide composition, Institute of O