7XQS | pdb_00007xqs

The structure of FLA-K*00701/KP-CoV-9

• PDB DOI: https://doi.org/10.2210/pdb7XQS/pdb

• Classification: IMMUNE SYSTEM
• Organism(s): Felis catus, Severe acute respiratory syndrome coronavirus 2
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2022-05-08 Released: 2023-11-08 
• Deposition Author(s): Qiao, P.W., Yue, C., Peng, W.Y., Liu, K.F., Huo, S.T., Zhang, D., Chai, Y., Qi, J.X., Sun, Z.Y., Gao, G.F., Liu, W.J., Wu, G.Z.
• Funding Organization(s): National Natural Science Foundation of China (NSFC)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.69 Å
• R-Value Free: 
  0.292 (Depositor), 0.290 (DCC) 
• R-Value Work: 
  0.223 (Depositor), 0.220 (DCC) 
• R-Value Observed: 
  0.226 (Depositor) 

Starting Model: experimental

Literature

Analysis of the characteristics of feline major histocompatibility complex class I molecules cross-presenting coronavirus peptides

Qiao, P.W., Yue, C., Peng, W.Y., Liu, K.F., Huo, S.T., Zhang, D., Chai, Y., Qi, J.X., Sun, Z.Y., Gao, G.F., Liu, W.J., Wu, G.Z.

To be published.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 3-mer - A1B1C1 

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

Biological Assembly Evidence: gel filtration

Macromolecule Content 

• Total Structure Weight: 46.32 kDa 
• Atom Count: 3,106 
• Modeled Residue Count: 381 
• Deposited Residue Count: 401 
• Unique protein chains: 3

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
MHC class I antigen alpha chain	A	274	Felis catus	Mutation(s): 0  Gene Names: FLA-I
UniProt
Find proteins for C6ZK69 (Felis catus) Explore C6ZK69  Go to UniProtKB:  C6ZK69

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Beta-2-microglobulin	B	118	Felis catus	Mutation(s): 0  Gene Names: B2M
UniProt
Find proteins for Q5MGS7 (Felis catus) Explore Q5MGS7  Go to UniProtKB:  Q5MGS7

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
peptide from Spike glycoprotein	C	9	Severe acute respiratory syndrome coronavirus 2	Mutation(s): 0
UniProt
Find proteins for P0DTC2 (Severe acute respiratory syndrome coronavirus 2) Explore P0DTC2  Go to UniProtKB:  P0DTC2

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.69 Å
• R-Value Free:  0.292 (Depositor), 0.290 (DCC) 
• R-Value Work:  0.223 (Depositor), 0.220 (DCC) 
• R-Value Observed: 0.226 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 54.292	α = 90
b = 70.829	β = 90
c = 121.347	γ = 90

Software Package:

Software Name	Purpose
autoPROC	data processing
PHENIX	refinement
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2023-11-08 
Deposition Author(s): Qiao, P.W., Yue, C., Peng, W.Y., Liu, K.F., Huo, S.T., Zhang, D., Chai, Y., Qi, J.X., Sun, Z.Y., Gao, G.F., Liu, W.J., Wu, G.Z.

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Funding Organization	Location	Grant Number
National Natural Science Foundation of China (NSFC)	China	--

Revision History  

• Version 1.0: 2023-11-08
  Type: Initial release
  
• Version 1.1: 2024-11-06
  Changes: Structure summary
• Version 1.2: 2026-03-04
  Changes: Refinement description