Identification of glycosylated sites in Rapana hemocyanin by mass spectrometry and gene sequence, and their antiviral effect.

Pavlina Dolashka-Angelova (1) , Bernhard Lieb (2) , Ludmila Velkova (1) , Nina Heilen (3) , Koen Sandra (4) , Lubomira Nikolaeva-Glomb (5) , Aleksander Dolashki (6) , Angel S Galabov (5) , Jozef van Beeumen (4) , Stefan Stevanovic (3) , Wolfgang Voelter (6) , Bart Devreese (4)

1 Institute of Organic Chemistry
2 Institute of Zoology
3 Department of Immunology, Institute for Cell Biology
4 Laboratory of Protein Biochemistry and Biomolecular Engineering
5 Institut Stephan Angeloff
6 Institute of Biochemistry

Molluscan hemocyanins (Hcs) have recently received particular interest due to their significant immunostimulatory properties. This is mainly related to their high carbohydrate content and specific monosaccharide composition. We have now analyzed the oligosaccharides and the carbohydrate linkage sites of the Rapana venosa hemocyanin (RvH) using different approaches. We analyzed a number of glycopeptides by LC/ESI-MS/MS and identified the sugar chains and peptide sequences of 12 glycopeptides. Additionally, the potential carbohydrate linkage sites of 2 functional units, RvH-b and RvH-c, were determined by gene sequence analysis. Only RvH-c shows a potential N-glycosylation site. During this study, we discovered a highly conserved linker-intron, separating the coding exons of RVH-b and RvH-c. Following reports on antiviral properties from arthropod hemocyanin, we conducted a preliminary study of the antiviral activity of RvH and the functional units RvH-b and RvH-c. We show that the glycosylated FU RvH-c has antiviral properties against the respiratory syncytial virus (RSV), whereas native RvH and the nonglycosylated FU RvH-b have not. This is the first report of the fact that also molluscan hemocyanin functional units possess antiviral activity.

Domaines: Microbiologie et Parasitologie

Pavlina Dolashka-Angelova, Bernhard Lieb, Ludmila Velkova, Nina Heilen, Koen Sandra, et al.. Identification of glycosylated sites in Rapana hemocyanin by mass spectrometry and gene sequence, and their antiviral effect.. Bioconjugate Chemistry, 2009, 20 (7), pp.1315-22. ⟨10.1021/bc900034k⟩. ⟨pasteur-00755459⟩