Functional characterization of two defensin isoforms of the hard tick Ixodes ricinus

0360134 - BC 2012 RIV GB eng J - Journal Article
Chrudimská, Tereza - Slaninová, Jiřina - Rudenko, Natalia - Růžek, Daniel - Grubhoffer, Libor
Functional characterization of two defensin isoforms of the hard tick Ixodes ricinus.
Parasites & Vectors. Roč. 4, č. 1 (2011), e63. ISSN 1756-3305. E-ISSN 1756-3305
R&D Projects: GA MŠMT(CZ) LC06009; GA ČR GA206/09/1782; GA ČR GD206/09/H026; GA ČR(CZ) GAP302/11/1901
Institutional research plan: CEZ:AV0Z60220518; CEZ:AV0Z40550506
Keywords : defensin * antimicrobial compounds * Ixodes ricinus
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 2.937, year: 2011

The immune system of ticks is stimulated to produce many pharmacologically active molecules during feeding and especially during pathogen invasion. Defensins represent a specific group of antimicrobial compounds with 6 conserved cysteine residues. Two isoforms of the defensin gene (def1 and def2) were identified in the European tick Ixodes ricinus. Expression of both genes was induced in different tick organs by a blood feeding or pathogen injection. Synthetic peptides def1 and def2 were shown to have antimicrobial activitiy against Gram+ bacteria, while Gram- bacteria, yeast, Tick Borne Encephalitis and West Nile Viruses were shown to be insensitive. In addition to antimicrobial activities, the hemolysis effect of def1 and def2 on human erythrocytes was also established. Defensins may play an important role in defence against different pathogens. Moreover this is a first report of a one amino acid substitution in a defensins molecule and its impact on antimicrobial activity.
Permanent Link: http://hdl.handle.net/11104/0197759