Functional expression and characterization of cathepsin B and L from the gut of the tick Ixodes ricinus

0336472 - BC 2010 RIV GB eng A - Abstract
Franta, Zdeněk - Pěničková, Helena - Dvorak, J. - Schneider, E. I. - Horn, Martin - Mareš, Michael - Sojka, Daniel - McKerrow, J. H. - Caffrey, C. R. - Kopáček, Petr
Functional expression and characterization of cathepsin B and L from the gut of the tick Ixodes ricinus.
FEBS Journal. Roč. 276, S1 (2009), s. 309-309. ISSN 1742-464X. E-ISSN 1742-4658.
[34th FEBS Congress: Life's Molecular Interactions. 04.07.2009-09.07.2009, Prague]
R&D Projects: GA AV ČR IAA600960910; GA MŠMT(CZ) LC06009
Institutional research plan: CEZ:AV0Z60220518; CEZ:AV0Z40550506
Keywords : cathepsin B and L * Ixodes ricinus * functionl expresssion
Subject RIV: EB - Genetics ; Molecular Biology

Ticks differ from hematophagous insects in intracellular localization of hemoglobin proteolysis. We have recently described in the hard tick Ixodes ricinus that this process occurs at acidic pH and as is maintained by a machinery of gut-associated cysteine and aspartic proteases similar to blood feeding platyhelmints and nematodes. In this work, we functionally expressed in Pichia pastoris and characterized two components of tick hemoglobinolytic cascade, namely IrCB and IrCL (cysteine proteases of CA family). Using a positional scanning of synthetic combinatorial library we identified the P1–P4 specifities of both enzymes. IrCL displays a strict acidic optimum at pH 4, while IrCB shows broader pH range. Both fusion enzymes were demonstrated to digest bovine hemoglobin and albumin in vitro. Expression profiles of both enzymes were strongly upregulated during blood meal uptake.
Permanent Link: http://hdl.handle.net/11104/0180696