32IR | pdb_000032ir

Alpha-Synuclein Type 6m Fibrils at pH 7.4 formed under strong agitation (coexisting with 6B and 2A in sample 44)

• PDB DOI: https://doi.org/10.2210/pdb32IR/pdb
• EM Map EMD-58924: EMDB EMDataResource

• Classification: PROTEIN FIBRIL
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2026-07-10 Released: 2026-10-21 
• Deposition Author(s): Frey, L., Kwiatkowski, W., Biedermann, K., Ghosh, D., Rhyner, D., Greenwald, J., Riek, R.
• Funding Organization(s): Swiss National Science Foundation, Other private

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.21 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

Literature

On the Polymorph-Selection Determinants of alpha-Synuclein Amyloid Fibrils Studied at Atomic Resolution

Frey, L., Rhyner, D., Kwiatkowski, W., Ghosh, D., Biedermann, K., Riek, R., Greenwald, J.

(2026) Elife 

• DOI: https://doi.org/10.7554/elife.112692.1

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 10-mer - A5B5 Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 10-mer - A5B1C1D1E1F1 

Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - B2 Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - B2 Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - B2 Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - B2 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 77.28 kDa 
• Atom Count: 1,955 
• Modeled Residue Count: 295 
• Deposited Residue Count: 760 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Alpha-synuclein	A, C, E, G, I	141	Homo sapiens	Mutation(s): 1  Gene Names: SNCA, NACP, PARK1
UniProt & NIH Common Fund Data Resources
Find proteins for P37840 (Homo sapiens) Explore P37840  Go to UniProtKB:  P37840
PHAROS:  P37840 GTEx:  ENSG00000145335

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
unidentified peptide segment	B, D, F, H, J	11	Homo sapiens	Mutation(s): 0

Small Molecules

Non-standard Monomers  1 Unique
ID	Chains	Type	Formula	2D Diagram
UNK	B, D, F, H, J	L-PEPTIDE LINKING	C4 H9 N O2

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.21 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

EM Software:

Task	Software Package	Version
RECONSTRUCTION	RELION	5.0.0

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-10-21 
Deposition Author(s): Frey, L., Kwiatkowski, W., Biedermann, K., Ghosh, D., Rhyner, D., Greenwald, J., Riek, R.

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Funding Organization	Location	Grant Number
Swiss National Science Foundation	Switzerland	--
Other private	Switzerland	2023-PI04

Revision History  

• Version 1.0: 2026-10-21
  Type: Initial release