This PhD project aims, through a combination of novel approaches, to firstly reduce the expression of glycosylated enzymes (glucocerebrosidase, α-galactosidase A, α-glucosidase) in yeasts for the treatment of LSD to levels sufficient to achieve a technically and commercially feasible process and, secondly, to improve its lysosome-specific delivery improve. Two yeast expression systems (Pichia pastoris, Yarrowia lipolytica) are already present in our lab present in which N-glycosylation is engrafted. These are capable, unlike their wild type precursors, to produce homogeneous glycoproteins with the human Man8GlcNAc2 structure as the 
sugar chain.