PDBsum entry 1kcs

Immune system

PDB id: 1kcs

Contents

Protein chains

214 a.a. *

217 a.a. *

Ligands

GLN-LEU-ASP-PRO-ALA-PHE-GLY

Waters ×85

* Residue conservation analysis

PDB id:

1kcs

Name:

Immune system

Title:

Crystal structure of antibody pc282 in complex with ps1 peptide

Structure:

Pc282 immunoglobulin. Chain: l. Fragment: light chain. Pc282 immunoglobulin. Chain: h. Fragment: heavy chain. Ps1 peptide. Chain: p. Engineered: yes

Source:

Mus musculus. House mouse. Organism_taxid: 10090. Synthetic: yes. Other_details: the peptide was chemically synthesized. The sequence of the peptide is naturally found in hepatitis b virus.

Biol. unit:

Trimer (from PQS)

Resolution:

2.50Å R-factor: 0.209 R-free: 0.277

Authors:

D.T.Nair,K.Singh,Z.Siddiqui,B.P.Nayak,K.V.S.Rao,D.M.Salunke

Key ref:

D.T.Nair et al. (2002). Epitope recognition by diverse antibodies suggests conformational convergence in an antibody response. J Immunol, 168, 2371-2382. PubMed id: 11859128

Date:

11-Nov-01 Release date: 11-May-02

Protein chain

P01837  (IGKC_MOUSE) -  Immunoglobulin kappa constant from Mus musculus

Seq: 107 a.a.

Struc: 214 a.a.*

Protein chain

P18532  (HVM61_MOUSE) -  Ig heavy chain V region 1B43 from Mus musculus

Seq: 116 a.a.

Struc: 217 a.a.*

* PDB and UniProt seqs differ at 30 residue positions (black crosses)

J Immunol 168:2371-2382 (2002)

PubMed id: 11859128

Epitope recognition by diverse antibodies suggests conformational convergence in an antibody response.

D.T.Nair, K.Singh, Z.Siddiqui, B.P.Nayak, K.V.Rao, D.M.Salunke.

ABSTRACT

Crystal structures of distinct mAbs that recognize a common epitope of a peptide Ag have been determined and analyzed in the unbound and bound forms. These Abs display dissimilar binding site structures in the absence of the Ag. The dissimilarity is primarily expressed in the conformations of complementarity-determining region H3, which is responsible for defining the epitope specificity. Interestingly, however, the three Abs exhibit similar complementarity-determining region conformations in the Ag binding site while recognizing the common epitope, indicating that different pathways of binding are used for Ag recognition. The epitope also exhibits conformational similarity when bound to each of these Abs, although the peptide Ag was otherwise flexible. The observed conformational convergence in the epitope and the Ag binding site was facilitated by the plasticity in the nature of interactions.