title: Peptide mixtures can self-assemble into large amyloid fibers of varying size and morphology.
abstract: Peptide mixtures spontaneously formed micrometer-sized fibers and ribbons from aqueous solution. Hydrolyzed gliadin produced short, slightly elliptical fibers while hydrolyzed wheat gluten, a mixture of gliadin and glutenin, formed round fibers of similar size. Mixing hydrolyzed gliadin with increasing molar amounts of myoglobin or amylase resulted in longer, wider fibers that transitioned from round to rectangular cross section. Fiber size, morphology, and modulus were controlled by peptide mixture composition. Fourier transform infrared (FT-IR) spectroscopy results showed that peptides experienced α to β transitions forming an elementary cross-β peptide secondary structure, indicative of amyloids. Large fiber formation was observed to be dependent on hydrophobic packing between constituent peptides. A model was developed to show how the fiber morphology was influenced by the peptides in the mixture.
authors: Biological Systems Engineering Department, Virginia Tech, 303 Seitz Hall, Blacksburg, Virginia 24061, United States.
authors: Devin M
authors: DM
authors: Ridgley
authors: Keira C
authors: KC
authors: Ebanks
authors: Justin R
authors: JR
authors: Barone
mesh_terms: D000681:Amylases / Q000737:chemistry; D000682:Amyloid / Q000032:analysis / Q000737:chemistry* / Q000648:ultrastructure; D040761:Biomimetic Materials / Q000032:analysis / Q000737:chemistry*; D002942:Circular Dichroism; D055119:Elastic Modulus; D005903:Gliadin / Q000737:chemistry; D005983:Glutens / Q000737:chemistry; D006868:Hydrolysis; D057927:Hydrophobic and Hydrophilic Interactions; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D009211:Myoglobin / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D010455:Peptides / Q000032:analysis / Q000737:chemistry*; D017433:Protein Structure, Secondary; D012996:Solutions; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000682:Amyloid; D009211:Myoglobin; D010455:Peptides; D012996:Solutions; D005983:Glutens; D005903:Gliadin; D000681:Amylases; C037302:glutenin