PDBsum entry 1jnh

Immune system

PDB id: 1jnh

Contents

Protein chains

208 a.a. *

214 a.a. *

Ligands

ECO ×4

Waters ×54

* Residue conservation analysis

PDB id:

1jnh

Name:

Immune system

Title:

Crystal structure of fab-estradiol complexes

Structure:

Monoclonal anti-estradiol 10g6d6 fab light chain. Chain: a, c, e, g. Synonym: fab 10g6 light chain. Monoclonal anti-estradiol 10g6d6 fab heavy chain. Chain: b, d, f, h. Synonym: fab 10g6 heavy chain

Source:

Mus musculus. House mouse. Organism_taxid: 10090. Other_details: ascetic fluid. Other_details: ascetic fluid

Biol. unit:

Dimer (from PQS)

Resolution:

2.85Å R-factor: 0.198 R-free: 0.253

Authors:

C.Monnet,F.Bettsworth,E.A.Stura,M.-H.Le Du,R.Menez,L.Derrien,S.Zinn- Justin,B.Gilquin,G.Sibai,N.Battail-Poirot,M.Jolivet,A.Menez, M.Arnaud,F.Ducancel,J.B.Charbonnier

Key ref:

C.Monnet et al. (2002). Highly specific anti-estradiol antibodies: structural characterisation and binding diversity. J Mol Biol, 315, 699-712. PubMed id: 11812141 DOI: 10.1006/jmbi.2001.5284

Date:

24-Jul-01 Release date: 06-Feb-02

Protein chains

P01843  (LAC1_MOUSE) -  Ig lambda-1 chain C region from Mus musculus

Seq: 105 a.a.

Struc: 208 a.a.*

Protein chains

No UniProt id for this chain

Struc: 214 a.a.

* PDB and UniProt seqs differ at 3 residue positions (black crosses)

DOI no: 10.1006/jmbi.2001.5284

J Mol Biol 315:699-712 (2002)

PubMed id: 11812141

Highly specific anti-estradiol antibodies: structural characterisation and binding diversity.

C.Monnet, F.Bettsworth, E.A.Stura, M.H.Le Du, R.Ménez, L.Derrien, S.Zinn-Justin, B.Gilquin, G.Sibaï, N.Battail-Poirot, M.Jolivet, A.Ménez, M.Arnaud, F.Ducancel, J.B.Charbonnier.

ABSTRACT

Subtle modulation of antibody-binding properties by protein engineering often lies with an accurate structural and energetic description of how an antigen is recognised. Thus, with the intent to increase the affinity and add a bias in favour of natural estradiol compared with its chemically modified immunogen, we have determined the crystal structure of two anti-estradiol monoclonal antibodies, 10G6D6 and 17E12E5. Although generated against the same estradiol derivative, these antibodies share little sequence identity, which is reflected in dissimilar binding pockets and in different positioning of the steroid. In both antibodies the characteristic 17-hydroxyl group is buried deeply at the bottom of hydrophobic pockets and stabilised by hydrogen bonds. Apart from this similarity, the steroid is oriented differently in the respective binding pockets. The high specificity of both antibodies has been mapped out, and even closely related steroids show low cross-reactivity. The structural studies of the complex formed between 10G6D6 and 6-CMO-estradiol have identified contacts between the 6-CMO coupling linker and an arginine residue from the heavy chain CDR2 segment. This segment is now being targeted by random mutagenesis to select mutants with a preference for natural estradiol compared to the branched hapten.

Selected figure(s)

Figure 1.
Figure 1. A representation of the steroid hormones used in this study. Ligands present in the crystal structure of antibodies 17E12 and 10G6 are (1) 17b-estradiol and (2) 17b-estradiol-6CMO. Numbering of atoms is shown on the structure of the 17b-estradiol. Cross-reactivity experiments were made with compounds 1 to 15. The antibodies were generated against 17b-estradiol-6EMC (16).

Figure 3.
Figure 3. Antibody-estradiol interactions (a) for Fab' 10G6 and (b) for Fab' 17E12. The view is in ball-and-stick of the main residues from the Fab' in contact with the estradiol and in broken lines of the hydrogen bonds with the O17 hydroxyl group. The estradiol, the V[H] and the V[L] regions are coloured in green, blue and yellow, respectively. The C6 atom of the estradiol, where the linker is attached, is represented in dark green. Figure 3, Figure 4 and Figure 5 were made with MOLMOL.[14]

The above figures are reprinted by permission from Elsevier: J Mol Biol (2002, 315, 699-712) copyright 2002.

Figures were selected by an automated process.