One advantage of P. pastoris as an expression system is its ability to perform eukaryotic post-translational modifications, including glycosylation, of heterologous proteins [23]. N-linked
glycosylation plays an essential role in protein secretion [24]. The recombinant Lipase GH1 displayed a broad MW of 40–66 kDa on SDS-PAGE, possibly as a result of glycosylation. Amino acid
sequence analysis indicated one potential N-glycosylation site (Asn-Xaa-Ser/Thr) that was identified by the NetNGlyc 1.0 server (http://www.cbs.dtu.dk/services/NetNGlyc/) at the 225 positio with the NAT motif. Deglycosylation of Lipase GH1 by Endo Hf resulted in a reduction of MW to 37 kDa (Fig. 2), equal to that reported by Chahinian et al. for deglycosylated partial acylglycerol lipase expressed in P. cyclopium [8]. We therefore presume that the difference in MW is due to different levels of glycosylation.