8TGT

Structure of human C4b-binding protein alpha chain CCP domains 1 and 2 in complex with the hypervariable region of group A Streptococcus M68 protein

• PDB DOI: https://doi.org/10.2210/pdb8TGT/pdb

• Classification: IMMUNE SYSTEM
• Organism(s): Streptococcus pyogenes, Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2023-07-13 Released: 2024-07-17 
• Deposition Author(s): Kolesinski, P., Ghosh, P.
• Funding Organization(s): National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.344 
• R-Value Work: 0.313 
• R-Value Observed: 0.316 

Literature

Structure of human C4b-binding protein alpha chain CCP domains 1 and 2 in complex with the hypervariable region of group A Streptococcus M68 protein

Kolesinski, P., Ghosh, P.

To be published.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 3-mer - A2B1 Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - A2 

Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - A2 

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

Macromolecule Content

• Total Structure Weight: 39.95 kDa 
• Atom Count: 1,632 
• Modelled Residue Count: 236 
• Deposited Residue Count: 336 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
M protein	A, B	104	Streptococcus pyogenes	Mutation(s): 0  Gene Names: emm
UniProt
Find proteins for Q6V9M3 (Streptococcus pyogenes) Explore Q6V9M3  Go to UniProtKB:  Q6V9M3

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
C4b-binding protein alpha chain	C	128	Homo sapiens	Mutation(s): 0  Gene Names: C4BPA, C4BP
UniProt & NIH Common Fund Data Resources
Find proteins for P04003 (Homo sapiens) Explore P04003  Go to UniProtKB:  P04003
PHAROS:  P04003 GTEx:  ENSG00000123838

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
EDO (Subject of Investigation/LOI)	H [auth C]	1,2-ETHANEDIOL C2 H6 O2 LYCAIKOWRPUZTN-UHFFFAOYSA-N
CA (Subject of Investigation/LOI)	D [auth A], E [auth A], F [auth B], G [auth B], I [auth C]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A, B	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.344 
• R-Value Work: 0.313 
• R-Value Observed: 0.316 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 107.037	α = 90
b = 49.664	β = 90
c = 80.403	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
XDS	data reduction
pointless	data scaling
Aimless	data scaling
AutoSol	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2024-07-17 
Deposition Author(s): Kolesinski, P., Ghosh, P.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)	United States	NIH R01 AI154149

Revision History  

• Version 1.0: 2024-07-17
  Type: Initial release