Spectroscopic evidence for amyloid-like interfacial self-assembly of hydrophobin Sc3.
Amphipathic fungal proteins called hydrophobins are able to self-assemble into insoluble supramolecular structures at hydrophobic/hydrophilic interfaces, but the molecular mechanism and underlying protein conformation changes are not known. Secondary-structure prediction indicated that hydrophobin Sc3 is an all-beta protein. Many amyloidogenic proteins self-assemble into insoluble amyloid fibrils while undergoing a change to an all-beta conformation. In this study we show that two dyes, thioflavin T, and Congo red, which are widely used for specific detection of stacked beta sheets, interact with Sc3 assemblies in the same way as with the amyloid beta-sheet fibrils. We conclude that Sc3, and probably other hydrophobins too, self-assemble at interfaces in the same manner as amyloidogenic proteins, i.e., through beta-sheet stacking.
Butko
P
P
Department of Chemistry & Biochemistry, University of Southern Mississippi, Hattiesburg, Mississippi 39406, USA.
Buford
J P
JP
Goodwin
J S
JS
Stroud
P A
PA
McCormick
C L
CL
Cannon
G C
GC
D016229:Amyloid beta-Peptides / Q000737:chemistry*; D000818:Animals; D052160:Benzothiazoles; D002417:Cattle; D003224:Congo Red / Q000737:chemistry; D005656:Fungal Proteins / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry*; D017433:Protein Structure, Secondary; D012567:Schizophyllum; D012710:Serum Albumin, Bovine; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry; D013844:Thiazoles / Q000737:chemistry
D016229:Amyloid beta-Peptides; D052160:Benzothiazoles; D005656:Fungal Proteins; D010446:Peptide Fragments; D013844:Thiazoles; C078592:amyloid beta-protein (1-40); C009462:thioflavin T; D012710:Serum Albumin, Bovine; D003224:Congo Red