Structure of the Anti-C60 Fullerene Antibody Fab Fragment: Structural Determinants of Fullerene Binding

The structure of the anti-C60 fullerene antibody Fab fragment (FabC60) was solved by X-ray crystallography. The computer-aided docking of C60 into the antigen-binding pocket of FabC60 showed that binding of C60 to FabC60 is governed by the enthalpy and entropy; namely, by - stacking interactions with aromatic residues of the antigen-binding site and reduction of the solvent-accessible area of the hydrophobic surface of C60. A fragment of the mobile CDR H3 loop located on the surface of FabC60 interferes with C60 binding in the antigen-binding site, thereby resulting in low antibody affinity for C60. The structure of apo-FabC60 has been deposited with pdbid 6H3H.

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Faculty Opinions recommendation of Variants of the antibody herceptin that interact with HER2 and VEGF at the antigen binding site.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1158476.618775 ◽

2009 ◽

Author(s):

Peter Colman ◽

Douglas Fairlie

Keyword(s):

Binding Site ◽

Antigen Binding ◽

Antigen Binding Site

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The mycoplasma surface proteins MIB and MIP promote the dissociation of the antibody-antigen interaction

Science Advances ◽

10.1126/sciadv.abf2403 ◽

2021 ◽

Vol 7 (10) ◽

pp. eabf2403

Author(s):

Pierre Nottelet ◽

Laure Bataille ◽

Geraldine Gourgues ◽

Robin Anger ◽

Carole Lartigue ◽

...

Keyword(s):

Surface Proteins ◽

Mycoplasma Species ◽

Antigen Binding ◽

Antigen Binding Site ◽

Fab Fragment ◽

Cryo Electron Microscopy ◽

Antigen Complex ◽

Antigen Interaction ◽

Immunoglobulin Binding

Mycoplasma immunoglobulin binding (MIB) and mycoplasma immunoglobulin protease (MIP) are surface proteins found in the majority of mycoplasma species, acting sequentially to capture antibodies and cleave off their VH domains. Cryo–electron microscopy structures show how MIB and MIP bind to a Fab fragment in a “hug of death” mechanism. As a result, the orientation of the VL and VH domains is twisted out of alignment, disrupting the antigen binding site. We also show that MIB-MIP has the ability to promote the dissociation of the antibody-antigen complex. This system is functional in cells and protects mycoplasmas from antibody-mediated agglutination. These results highlight the key role of the MIB-MIP system in immunity evasion by mycoplasmas through an unprecedented mechanism, and open exciting perspectives to use these proteins as potential tools in the antibody field.

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Uncommon structural motifs dominate the antigen binding site in human autoantibodies reactive with basement membrane collagen

Molecular Immunology ◽

10.1016/j.molimm.2016.07.004 ◽

2016 ◽

Vol 76 ◽

pp. 123-133 ◽

Cited By ~ 1

Author(s):

Mary H. Foster ◽

Elizabeth S. Buckley ◽

Benny J. Chen ◽

Kwan-Ki Hwang ◽

Amy G. Clark

Keyword(s):

Basement Membrane ◽

Binding Site ◽

Antigen Binding ◽

Antigen Binding Site ◽

Structural Motifs ◽

Basement Membrane Collagen ◽

Membrane Collagen

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A shared idiotype among human anti-Ro/SSA autoantibodies.

Journal of Experimental Medicine ◽

10.1084/jem.169.5.1583 ◽

1989 ◽

Vol 169 (5) ◽

pp. 1583-1588 ◽

Cited By ~ 5

Author(s):

K K Gaither ◽

J B Harley

Keyword(s):

Binding Site ◽

Heart Block ◽

Congenital Heart ◽

Congenital Heart Block ◽

Antigen Binding ◽

Normal Donor ◽

Neonatal Lupus ◽

Antigen Binding Site ◽

Fine Specificity ◽

Low Level

Idiotypes and antiidiotypes are thought to be important immune regulators and have provided clues for the origin and pathogenicity of autoantibodies. Many lupus and Sjögren's syndrome patients, as well as most neonatal lupus infants with congenital heart block or dermatitis, have antibodies to the ribonucleoprotein Ro/SSA, which is one of a group of RNA-protein autoantigens commonly found in human lupus sera. To characterize the fine specificity of anti-Ro/SSA antibodies, a rabbit antidiotypic serum was prepared against polyclonal affinity purified anti-Ro/SSA F(ab')2. The resulting antiidiotype, anti-Id-Rol, is specific for the F(ab')2 fraction of the anti-Ro/SSA immunogen and its binding to anti-Ro/SSA is inhibited by purified Ro/SSA. These data indicate that the Id-Rol epitope on anti-Ro/SSA is associated with the antigen binding site of these same antibodies. The Id-Rol idiotype was present by ELISA in 3 of 12 additional anti-Ro/SSA preparations from precipitin-positive donor sera and in anti-Ro/SSA from one normal donor with low level antibody. This is the first shared idiotype to be found in the human autoantibodies binding to this RNA-protein antigen. Idiotypic differences between anti-Ro/SSA autoantibodies have the potential to explain the variation in pathologic associations found in individuals who develop this autoantibody specificity.

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