the antigen affects the valence or number of bonds through weak chemical interactions.
the antigen affects the valence or number of bonds through weak chemical interactions.
when does the antigen affect the valence or number of bonds?
through weak chemical interactions
section::::properties.









































section::::properties.:chemical basis of antigen-antibody interaction.









































antibodies bind antigens through weak chemical interactions, and bonding is essentially non-covalent. electrostatic interactions, hydrogen bonds, van der waals forces, and hydrophobic interactions are all known to be involved depending on the interaction sites. non-covalent bonds between antibody and antigen can also be mediated by interfacial water molecules. such indirect bonds can contribute to the phenomenon of cross-reactivity, i.e. the recognition of different but related antigens by a single antibody.









































section::::properties.:affinity of the interaction.
antigen-antibody interaction
the antibody has a three-dimensional structure with beta pleated sheet and alpha helices. the antibody folds so the variable regions form three loops with the framework regions folded into one another and the cdr regions on the tips of each of these loops in direct contact with the antigen. residues are short amino acid sequences, residues of the framework region responsible for supporting the binding of the antigen to the antibody can be divided into two categories; residues that are in contact with the antigen and those not in contact with the antigen. framework residues that come in contact with the antigen are a part of the antibody's binding site, and are located either close in sequence to the cdrs or in close proximity to the cdr when in the folded three dimensional structure. framework residues that do not come in contact with the antigen affect the binding indirectly by aiding in structural support for the cdr. this enables the cdr to take on the correct orientation and position so it is exposed on the surface of the chain ready to bind to an antigen.
framework region