Authors

P McVeigh²; K Cwiklinski²; G V Mulcahy³; S M O'Neil¹; A G Maule²; J P Dalton²;  ¹ Dublin City University, Ireland;  ² Queen's University Belfast;  ³ University College Dublin, Ireland

Discussion

Glycosylation represents a major mechanism of eukaryotic post-translational modification, where specific polysaccharide sugars (glycans) are attached to proteins and lipids. These modifications are essential for correct protein folding and also confer structural and functional complexity onto recipient proteins. In helminths, glycosylation likely determines the immunogenicity of parasite proteins at the host-parasite interface, and is therefore of interest from a control perspective. The structure,function, and biosynthesis of helminth glycans nevertheless remains poorly understood. We have identified >100 genes from the Fasciola hepaticagenome with homology to glycosylationcomponents from model organisms. Using well annotated eukaryotic pathways as a template, we have attempted to reconstruct the liver fluke glycosylation pathway. Our data suggest that fluke lack some of the enzymes required to produce complex glycans; of particular interest is the apparent absence of enzymes associated with sialylation from the F. hepatica genome. We are currently investigating the function of selected aspects of glycosylation using a battery of enzymes and functional genomics tools targeted to chokepoints within the glycosylation pathway.