PDBe 2x4o

X-ray diffraction
2.3Å resolution

Crystal structure of MHC CLass I HLA-A2.1 bound to HIV-1 envelope peptide env120-128

Primary publication:
UV-induced ligand exchange in MHC class I protein crystals.
J. Am. Chem. Soc. 131 12298-304 (2009)
PMID: 19655750

Function and Biology Details

Structure analysis Details

Assembly composition:
hetero trimer (preferred)
Entry contents:
3 distinct polypeptide molecules
Macromolecules (3 distinct):
HLA class I histocompatibility antigen, A-2 alpha chain Chains: A, D
Molecule details ›
Chains: A, D
Length: 275 amino acids
Theoretical weight: 31.85 KDa
Source organism: Homo sapiens
Expression system: Escherichia coli BL21(DE3)
  • Canonical: P01892 (Residues: 25-299; Coverage: 81%)
Gene names: HLA-A, HLAA
Sequence domains:
Structure domains:
Beta-2-microglobulin Chains: B, E
Molecule details ›
Chains: B, E
Length: 100 amino acids
Theoretical weight: 11.88 KDa
Source organism: Homo sapiens
Expression system: Escherichia coli
  • Canonical: P61769 (Residues: 21-119; Coverage: 100%)
Gene names: B2M, CDABP0092, HDCMA22P
Sequence domains: Immunoglobulin C1-set domain
Structure domains: Immunoglobulins
Surface protein gp120 Chains: C, F
Molecule details ›
Chains: C, F
Length: 9 amino acids
Theoretical weight: 988 Da
Source organism: Human immunodeficiency virus 1
Expression system: Not provided
  • Canonical: P04583 (Residues: 120-128; Coverage: 1%)
Gene name: env

Ligands and Environments

2 bound ligands:

No modified residues

Experiments and Validation Details

Entry percentile scores
X-ray source: ESRF BEAMLINE ID23-1
Spacegroup: P21
Unit cell:
a: 61.988Å b: 81.904Å c: 79.748Å
α: 90° β: 90.87° γ: 90°
R R work R free
0.178 0.175 0.239
Expression systems:
  • Escherichia coli BL21(DE3)
  • Escherichia coli
  • Not provided