A radish seed antifungal peptide with a high amyloid fibril-forming propensity

作者：Garvey Megan; Meehan Sarah; Gras Sally L; Schirra Horst J; Craik David J; Van der Weerden Nicole L; Anderson Marilyn A; Gerrard Juliet A; Carver John A^*

来源：Biochimica et Biophysica Acta-Proteins and Proteomics, 2013, 1834(8): 1615-1623.

DOI：10.1016/j.bbapap.2013.04.030

• Amyloid fibril
• Antifungal peptide
• Antimicrobial peptide
• Protein misfolding
• Protein aggregation

The amyloid fibril-forming ability of two closely related antifungal and antimicrobial peptides derived from plant defensin proteins has been investigated. As assessed by sequence analysis, thioflavin T binding, transmission electron microscopy, atomic force microscopy and X-ray fiber diffraction, a 19 amino acid fragment from the C-terminal region of Raphanus sativus antifungal protein, known as RsAFP-19, is highly amyloidogenic. Further, its fibrillar morphology can be altered by externally controlled conditions. Freezing and thawing led to amyloid fibril formation which was accompanied by loss of RsAFP-19 antifungal activity. A second, closely related antifungal peptide displayed no fibril-forming capacity. It is concluded that while fibril formation is not associated with the antifungal properties of these peptides, the peptide RsAFP-19 is of potential use as a controllable, highly amyloidogenic small peptide for investigating the structure of amyloid fibrils and their mechanism of formation.

• 出版日期2013-8