11ZN | pdb_000011zn

Structure of peptide segment KLVFFA from amyloid-beta determined by MicroED under cryogenic temperatures

• PDB DOI: https://doi.org/10.2210/pdb11ZN/pdb

• Classification: PROTEIN FIBRIL
• Organism(s): synthetic construct
• Mutation(s): No 


• Deposited: 2026-03-19 Released: 2026-11-11 
• Deposition Author(s): Flowers, C.W., Vlahakis, N.W.
• Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

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Experimental Data Snapshot

• Method: ELECTRON CRYSTALLOGRAPHY
• Resolution: 1.50 Å
• R-Value Free: 
  0.339 (Depositor), 0.340 (DCC) 
• R-Value Work: 
  0.305 (Depositor), 0.327 (DCC) 
• R-Value Observed: 
  0.309 (Depositor) 

Literature

Room Temperature Structures of Solvated Organic Molecules Enabled by Liquid Cell Electron Diffraction.

Vlahakis, N.W., Konieczny, K., Flowers, C.W., Garcia-Garibay, M.A., Rodriguez, J.A.

(2026) ACS Cent Sci 12: 1592-1600

• PubMed: 42964980 
• DOI: https://doi.org/10.1021/acscentsci.6c00603
• Primary Citation Related Structures: 
  11ZN, 9Q2V


• PubMed Abstract: 
  

  Electron diffraction (MicroED/3DED) enables atomic structure determination from nano- or microcrystals, including dry crystalline powders or mixtures. However, radiation damage and instrument vacuum can limit the interrogation of molecular crystals in solution at room temperature. We now present a strategy for room-temperature MicroED of organic molecular microcrystals suspended in solution, using simple liquid cells: grid sandwiches comprised of two continuous carbon grids that when pressed retain a thin liquid layer between them. In this setting, we find that some room-temperature, hydrated microcrystals are particularly prone to electron beam radiation damage, requiring fast, low dose data collection schemes, direct electron detectors, and multi-crystal data collection. These approaches minimize damage of crystals in liquid cells and facilitate ab initio structures at sub-Ångstrom resolution. This tactic enables study of molecular conformations and crystalline phases that may only be accessible in a room-temperature solvated state.

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Organizational Affiliation: 
• Department of Chemistry and Biochemistry, University of California, Los Angeles (UCLA), Los Angeles, California 90095, United States.
UCLA-DOE Institute for Genomics and Proteomics; STROBE, NSF Science and Technology Center, University of California, Los Angeles (UCLA), Los Angeles, California 90095, United States.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 0.72 kDa 
• Atom Count: 53 
• Modeled Residue Count: 6 
• Deposited Residue Count: 6 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
LYS-LEU-VAL-PHE-PHE-ALA	A	6	synthetic construct	Mutation(s): 0

Experimental Data & Validation

Experimental Data

• Method: ELECTRON CRYSTALLOGRAPHY
• Resolution: 1.50 Å
• R-Value Free:  0.339 (Depositor), 0.340 (DCC) 
• R-Value Work:  0.305 (Depositor), 0.327 (DCC) 
• R-Value Observed: 0.309 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 9.74	α = 90
b = 12.54	β = 90
c = 42.26	γ = 90

EM Software:

Task	Software Package	Version
RECONSTRUCTION	PHENIX

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-11-11 
Deposition Author(s): Flowers, C.W., Vlahakis, N.W.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	R35 GM128867,

Revision History  

• Version 1.0: 2026-11-11
  Type: Initial release