6FGR

Crystal Structure of the Amyloid-like IIKIIK Segment from the S. aureus Biofilm-associated PSMalpha4

Summary for 6FGR

• Entry DOI: 10.2210/pdb6fgr/pdb
• Related: 6FG4
• Descriptor: Psm alpha-4, 1,2-ETHANEDIOL, SULFATE ION, ... (4 entities in total)
• Functional Keywords: steric-zipper, cross-beta, bacterial amyloid fibril, s. aureus, psm, protein fibril
• Biological source: Staphylococcus aureus
• Total number of polymer chains: 2
• Total formula weight: 1712.21

Authors

Landau, M.,Colletier, J.-P. (deposition date: 2018-01-11, release date: 2018-08-08, Last modification date: 2024-05-01)

Primary citation

Salinas, N.,Colletier, J.P.,Moshe, A.,Landau, M.
Extreme amyloid polymorphism in Staphylococcus aureus virulent PSM alpha peptides.
Nat Commun, 9:3512-3512, 2018

PubMed Abstract: Members of the Staphylococcus aureus phenol-soluble modulin (PSM) peptide family are secreted as functional amyloids that serve diverse roles in pathogenicity and may be present as full-length peptides or as naturally occurring truncations. We recently showed that the activity of PSMα3, the most toxic member, stems from the formation of cross-α fibrils, which are at variance with the cross-β fibrils linked with eukaryotic amyloid pathologies. Here, we show that PSMα1 and PSMα4, involved in biofilm structuring, form canonical cross-β amyloid fibrils wherein β-sheets tightly mate through steric zipper interfaces, conferring high stability. Contrastingly, a truncated PSMα3 has antibacterial activity, forms reversible fibrils, and reveals two polymorphic and atypical β-rich fibril architectures. These architectures are radically different from both the cross-α fibrils formed by full-length PSMα3, and from the canonical cross-β fibrils. Our results point to structural plasticity being at the basis of the functional diversity exhibited by S. aureus PSMαs.

PubMed: 30158633
DOI: 10.1038/s41467-018-05490-0

Experimental method

X-RAY DIFFRACTION (1.5 Å)