5I55

Crystal Structure of the Virulent PSM-alpha3 Peptide Forming a Cross-alpha amyloid-like Fibril

Summary for 5I55

• Entry DOI: 10.2210/pdb5i55/pdb
• Descriptor: Psm alpha-3, (4S)-2-METHYL-2,4-PENTANEDIOL, ACETATE ION, ... (4 entities in total)
• Functional Keywords: the cross-alpha amyloid-like fold is composed of mating alpha-helical sheets, protein fibril
• Biological source: Staphylococcus aureus
• Total number of polymer chains: 1
• Total formula weight: 2835.26

Authors

Landau, M.,Moshe, A.,Tayeb-Fligelman, E.,Sawaya, M.R.,Coquelle, N.,Colletier, J.-P. (deposition date: 2016-02-14, release date: 2017-03-01, Last modification date: 2024-10-09)

Primary citation

Tayeb-Fligelman, E.,Tabachnikov, O.,Moshe, A.,Goldshmidt-Tran, O.,Sawaya, M.R.,Coquelle, N.,Colletier, J.P.,Landau, M.
The cytotoxic Staphylococcus aureus PSM alpha 3 reveals a cross-alpha amyloid-like fibril.
Science, 355:831-833, 2017

PubMed Abstract: Amyloids are ordered protein aggregates, found in all kingdoms of life, and are involved in aggregation diseases as well as in physiological activities. In microbes, functional amyloids are often key virulence determinants, yet the structural basis for their activity remains elusive. We determined the fibril structure and function of the highly toxic, 22-residue phenol-soluble modulin α3 (PSMα3) peptide secreted by PSMα3 formed elongated fibrils that shared the morphological and tinctorial characteristics of canonical cross-β eukaryotic amyloids. However, the crystal structure of full-length PSMα3, solved de novo at 1.45 angstrom resolution, revealed a distinctive "cross-α" amyloid-like architecture, in which amphipathic α helices stacked perpendicular to the fibril axis into tight self-associating sheets. The cross-α fibrillation of PSMα3 facilitated cytotoxicity, suggesting that this assembly mode underlies function in .

PubMed: 28232575
DOI: 10.1126/science.aaf4901

Experimental method

X-RAY DIFFRACTION (1.45 Å)