8K3A | pdb_00008k3a

SOD1 and Nanobody2 complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.74 Å
  • R-Value Free: 
    0.256 (Depositor), 0.260 (DCC) 
  • R-Value Work: 
    0.234 (Depositor), 0.240 (DCC) 
  • R-Value Observed: 
    0.235 (Depositor) 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural mechanisms and insights on multiple nanobodies binding diverse SOD1 epitopes.

Cheng, S.Zhong, C.Zhu, H.Mu, K.Jiang, H.Zhong, P.Ma, Z.Liu, X.Wang, Z.Liu, R.Ding, Y.

(2025) Commun Biol 9: 30-30

  • DOI: https://doi.org/10.1038/s42003-025-09293-0
  • Primary Citation of Related Structures:  
    8K33, 8K3A, 8K3L, 8YAF, 8YAT

  • PubMed Abstract: 

    Copper/zinc superoxide dismutase (SOD1) is a crucial metalloenzyme that mitigates oxidative stress by scavenging superoxide anion radicals. Mutations and aggregation of SOD1 are closely linked to the pathogenesis of amyotrophic lateral sclerosis (ALS). Targeting pathogenic SOD1 with nanobodies presents a promising therapeutic approach. We report the first high-resolution crystal structures of SOD1 in complex with three distinct nanobodies (Nb1, Nb2, and Nb3) and their multimeric assemblies (1:2 and 1:3 stoichiometries), revealing distinct binding epitopes primarily mediated by their complementarity determining regions (CDRs) through hydrogen bonds, salt bridges, and hydrophobic interactions. Structural and biophysical analyses using isothermal titration calorimetry (ITC) and fluorescence-detection size-exclusion chromatography (FSEC) demonstrated that all three nanobodies bind SOD1 simultaneously with nanomolar affinities (K D values ranging from 23.2 nM to 529 nM). Notably, engineered multimeric tandem nanobodies (Nb1-Nb2-Nb3) achieved higher affinity (K D  = 4.39 nM) compared to single nanobodies, as validated by ITC. Characterization via dynamic light scattering (DLS) further revealed colloidal stability of SOD1-nanobody complexes. These results provide the first atomic-resolution insights into multi-nanobody targeting of SOD1 without steric interference, establishing a foundation for developing high-affinity tools to detect and manipulate SOD1 in ALS and related neurodegenerative diseases.


  • Organizational Affiliation
    • State Key Laboratory of Genetics and Development of Complex Phenotypes, School of Life Sciences, Fudan University, Shanghai, China.

Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Superoxide dismutase [Cu-Zn]153Homo sapiensMutation(s): 0 
Gene Names: SOD1
EC: 1.15.1.1 (PDB Primary Data), 1.8 (UniProt)
UniProt & NIH Common Fund Data Resources
Find proteins for P00441 (Homo sapiens)
Explore P00441 
Go to UniProtKB:  P00441
PHAROS:  P00441
GTEx:  ENSG00000142168 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00441
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
NB2131Camelus dromedariusMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download Ideal Coordinates CCD File 
C [auth A]ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.74 Å
  • R-Value Free:  0.256 (Depositor), 0.260 (DCC) 
  • R-Value Work:  0.234 (Depositor), 0.240 (DCC) 
  • R-Value Observed: 0.235 (Depositor) 
Space Group: P 6
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 113.29α = 90
b = 113.29β = 90
c = 66.849γ = 120
Software Package:
Software NamePurpose
PHENIXrefinement
XDSdata scaling
XDSdata reduction
PHENIXphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data

  • Released Date: 2024-07-17 
  • Deposition Author(s): Cheng, S.

Funding OrganizationLocationGrant Number
Ministry of Science and Technology (MoST, China)China2021YFA0805200
National Science Foundation (NSF, China)China32070939
National Science Foundation (NSF, China)China82030106

Revision History  (Full details and data files)

  • Version 1.0: 2024-07-17
    Type: Initial release
  • Version 1.1: 2024-10-30
    Changes: Structure summary
  • Version 1.2: 2026-01-28
    Changes: Database references