Related Experiment Videos
Long-range changes in a protein antigen due to antigen-antibody interaction
D C Benjamin1, D C Williams, S J Smith-Gill
1Department of Microbiology, University of Virginia, Charlottesville 22908.
Biochemistry
|October 23, 1992
Summary
Antibody binding to hen egg-white lysozyme alters amide exchange rates, even at residues far from the antibody
Area of Science:
- Biochemistry
- Structural Biology
- Immunology
Background:
- Antibody-antigen interactions are crucial in biological systems.
- Understanding conformational changes in antigens upon antibody binding is important.
- Hen egg-white lysozyme serves as a model antigen.
Purpose of the Study:
- To investigate conformational changes in hen egg-white lysozyme upon binding to the anti-lysozyme monoclonal antibody HyHEL-5.
- To probe the extent of these conformational changes using amide exchange kinetics.
Main Methods:
- Utilized amide exchange kinetics to study protein conformation.
- Employed two-dimensional Nuclear Magnetic Resonance (2D NMR) spectroscopy.
- Measured amide proton exchange rates in the lysozyme-antibody complex.
Main Results:
- Fifteen amide protons in lysozyme exhibited altered exchange kinetics when complexed with HyHEL-5.
- Changes were observed in residues within, at the perimeter of, and distant from the antibody epitope.
- Perturbations extended to residues located away from the defined structural epitope.
Conclusions:
- Antigen-antibody complex formation can induce conformational alterations in the antigen at sites remote from the epitope.
- Amide exchange kinetics is a sensitive method for detecting these distant conformational changes.
- This highlights the potential for allosteric effects in antigen-antibody interactions.