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Hydrophobin gene expression affects hyphal wall composition in Schizophyllum commune.

M A van Wetter·H A Wösten·J H Sietsma·J G Wessels
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Abstract

Disruption of the SC3 hydrophobin gene of Schizophyllum commune (DeltaSC3 strain) affected the composition of the cell wall. Compared to a wild-type strain the amount of mucilage (i.e., water-soluble (1-3)beta-glucan with single glucose residues attached by (1-6)beta-linkages) increased considerably, while the amount of alkali-resistant glucan (linked to chitin) decreased. Reintroduction of the SC3 gene or other hydrophobins genes expressed behind the SC3 promotor restored wild-type cell wall composition. However, addition of purified SC3 protein to the medium or growing the DeltaSC3 strain in spent medium of the wild-type strain had no effect. In young cultures of wild-type strains of S.commune, not yet expressing SC3, the amount of mucilage was also relatively high. These data show that hydrophobins not only function at hydrophilic/hydrophobic interfaces, as shown previously, but also affect wall composition.

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Cell WallCulture MediaFungal ProteinsSchizophyllumJournal ArticleResearch Support, Non-U.S. Gov't

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M A van Wetter, H A Wösten, J H Sietsma, J G Wessels. 2000. Hydrophobin gene expression affects hyphal wall composition in Schizophyllum commune.. https://doi.org/10.1006/fgbi.2000.1231

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