INTERFACIAL SELF-ASSEMBLY OF A HYDROPHOBIN INTO AN AMPHIPATHIC PROTEIN MEMBRANE MEDIATES FUNGAL ATTACHMENT TO HYDROPHOBIC SURFACES

The SC3p hydrophobin of Schizophyllum commune is a small hydrophobic p rotein (100-101 amino acids with eight cysteine residues) that self-as sembles at a water/air interface and coats aerial hyphae with an SDS-i nsoluble protein membrane, at the outer side highly hydrophobic and wi th a typical rodlet pattern. SC3p monomers in water also self-assemble at the interfaces between water and oils or hydrophobic solids. These materials are then coated with a 10 nm thick SDS-insoluble assemblage of SC3p making their surfaces hydrophilic. Hyphae of S.commune growin g on a Teflon surface became firmly attached and SC3p was shown to be present between the fungal cell wail and the Teflon. Decreased attachm ent of hyphae to Teflon was observed in strains not expressing SC3, i. e. a strain containing a targeted mutation in this gene and a regulato ry mutant thn. These findings indicate that hydrophobins, in addition to forming hydrophobic wall coatings, play a role in adherence of fung al hyphae to hydrophobic surfaces.