Conformational epitope

The term "conformational epitope", also called discontinuous epitope, refers to an allergenic binding site of e.g. a protein defined by the three-dimensional secondary or tertiary structure of the protein.

An allergen is a protein or glycoprotein with one or more binding sites for specific antibodies called epitopes. An antigen-specific primary antibody binds with a characteristic molecular mass only to "its" epitope on the antigen in question. This may be a sequence epitope (continuous or linear epitope) determined by the primary sequence of the protein.

Alternatively, binding to a conformational epitope is possible. This is determined by the secondary or tertiary structure of the protein.

There are various chemical possibilities to characterize the allergenic proteins in more detail. The exact determination of a sequence or conformational epitope can be carried out by structural investigations. Epitopes, in particular the conformational epitopes, of a food can be altered during the technological processing of a food so that the allergenic potential is reduced, in rare cases even increased. The different heating processes, such as pasteurisation, for example, play a role here

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