Filamentous fungi as production organisms for glycoproteins of bio-medicalinterest

Filamentous fungi are commonly used in the fermentation industry for large scale production of glycoproteins. Several of these proteins can be produce d in concentrations up to 20-40 g per litre. The production of heterologous glycoproteins is at least one or two orders of magnitude lower but researc h is in progress to increase the production levels. In the past years the s tructure of protein-linked carbohydrates of a number of fungal proteins has been elucidated, showing the presence of oligo-mannosidic and high-mannose chains, sometimes with typical fungal modifications. A start has been made to engineer the glycosylation pathway in filamentous fungi to obtain strai ns that show a more mammalian-like type of glycosylation. This mini review aims to cover the current knowledge of glycosylation in filamentous fungi, and to show the possibilities to produce glycoproteins with these organisms with a more mammalian-like type of glycosylation for research purposes or pharmaceutical applications.