26KA | pdb_000026ka

Cryo-EM structure of Crimean-Congo hemorrhagic fever virus RNA polymerase in complex with the 5' vRNA promotor from the 5'/3' vRNA dual-promoter dataset

• PDB DOI: https://doi.org/10.2210/pdb26KA/pdb
• EM Map EMD-80707: EMDB EMDataResource

• Classification: RNA BINDING PROTEIN/RNA
• Organism(s): Orthonairovirus haemorrhagiae
• Expression System: Homo sapiens
• Mutation(s): No 


• Deposited: 2026-05-04 Released: 2026-08-19 
• Deposition Author(s): Ma, J., Yang, K., Wu, H., Liu, X., Liang, Z.
• Funding Organization(s): Not funded

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.03 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Starting Model: in silico

Literature

Cryo-EM structures of CCHFV polymerase reveal a stepwise initiation stabilization pathway and a dual-site inhibition mechanism

Yang, K., Wu, H., Liu, X., Ma, J.

To be published.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors and generated by (software)

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 456.5 kDa 
• Atom Count: 11,752 
• Modeled Residue Count: 1,507 
• Deposited Residue Count: 3,989 
• Unique protein chains: 1
• Unique nucleic acid chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
RNA-directed RNA polymerase L	A	3,974	Orthonairovirus haemorrhagiae	Mutation(s): 0  EC: 3.4.19.12 (PDB Primary Data), 3.4.22 (PDB Primary Data), 3.1 (PDB Primary Data), 2.7.7.48 (PDB Primary Data)
UniProt
Find proteins for Q6TQR6 (Crimean-Congo hemorrhagic fever virus (strain Nigeria/IbAr10200/1970)) Explore Q6TQR6  Go to UniProtKB:  Q6TQR6

Entity ID: 2
Molecule	Chains	Length	Organism	Image
5' vRNA promoter	B	15	Orthonairovirus haemorrhagiae

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ZN (Subject of Investigation/LOI)	C [auth A], D [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N
MN (Subject of Investigation/LOI)	E [auth A]	MANGANESE (II) ION Mn WAEMQWOKJMHJLA-UHFFFAOYSA-N
MG	F [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.03 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	PHENIX	1.20.1_4487
RECONSTRUCTION	cryoSPARC

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-08-19 
Deposition Author(s): Ma, J., Yang, K., Wu, H., Liu, X., Liang, Z.

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Funding Organization	Location	Grant Number
Not funded		--

Revision History  

• Version 1.0: 2026-08-19
  Type: Initial release