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Identification of alg3 in the mushroom forming fungus Schizophyllum commune and analysis of the {triangleup}alg3 knockout mutant.

Institute of Cell Biology and Plant Biochemistry, University of Regensburg, 93053 Regensburg, Germany.
Glycobiology (Impact Factor: 3.75). 09/2012; DOI: 10.1093/glycob/cws135
Source: PubMed

ABSTRACT Alg3 of Saccharomyces cerevisiae catalyzes the mannosyl transfer from Man-P-Dol to Man(5)GlcNAc(2)-PP-Dol resulting in the formation of Man(6)GlcNAc(2)-PP-Dol, which is then further processed to the final precursor oligosaccharide Glc(3)Man(9)GlcNAc(2) for N-glycosylation of proteins. Here, we identified the alg3 gene of the mushroom forming fungus Schizophyllum commune by homology search. Its function was confirmed by complementation of the Δalg3 strain of S. cerevisiae. Inactivation of alg3 in S. commune resulted in production of predominantly Man(3)GlcNAc(2) protein-linked N-glycans. No impact on growth nor a developmental phenotype due to the deletion was observed. This provides a first step towards engineering of a homogeneous, humanized N-glycosylation pattern for the production of therapeutic glycoproteins in mushrooms.

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