1JWS

Crystal Structure of the Complex of the MHC Class II Molecule HLA-DR1 (HA peptide 306-318) with the Superantigen SEC3 Variant 3B1

Summary for 1JWS

• Entry DOI: 10.2210/pdb1jws/pdb
• Related: 1JWM 1JWU
• Descriptor: HLA class II histocompatibility antigen, DR alpha chain, HLA class II histocompatibility antigen, DR-1 beta chain, HA peptide, ... (5 entities in total)
• Functional Keywords: hla-dr1 alpha subunit, hla-dr1 beta subunit, mutation, immune system
• Biological source: Homo sapiens (human); More
• Cellular location: Cell membrane; Single-pass type I membrane protein: P01903 P04229; Secreted: P0A0L5
• Total number of polymer chains: 4
• Total formula weight: 72403.36

Authors

Sundberg, E.J.,Andersen, P.S.,Schlievert, P.M.,Karjalainen, K.,Mariuzza, R.A. (deposition date: 2001-09-05, release date: 2003-07-08, Last modification date: 2024-10-30)

Primary citation

Sundberg, E.J.,Andersen, P.S.,Schlievert, P.M.,Karjalainen, K.,Mariuzza, R.A.
Structural, energetic, and functional analysis of a protein-protein interface at distinct stages of affinity maturation
Structure, 11:1151-1161, 2003

PubMed Abstract: Due to a paucity of studies that synthesize structural, energetic, and functional analyses of a series of protein complexes representing distinct stages in an affinity maturation pathway, the biophysical basis for the molecular evolution of protein-protein interactions is poorly understood. Here, we combine crystal structures and binding-free energies of a series of variant superantigen (SAG)-major histocompatibility complex (MHC) class II complexes exhibiting increasingly higher affinity to reveal that this affinity maturation pathway is controlled largely by two biophysical factors: shape complementarity and buried hydrophobic surface. These factors, however, do not contribute equivalently to the affinity maturation of the interface, as the former dominates the early steps of the maturation process while the latter is responsible for improved binding in later steps. Functional assays reveal how affinity maturation of the SAG-MHC interface corresponds to T cell activation by SAGs.

PubMed: 12962633
DOI: 10.1016/S0969-2126(03)00187-4

Experimental method

X-RAY DIFFRACTION (2.6 Å)