Whats the difference between a linear epitope and a conformational epitope?
A linear epitope consists of about 6 to 10 adjacent amino acids on a protein molecule that is recognized by an antibody. In contrast, conformational epitope consists of amino acids that are not arranged sequentially. Here the antibody recognizes only the 3-dimensional structure. When a protein molecule folds into a three dimensional structure the amino acids forming the epitope are juxtaposed enabling the antibody to recognize the sequence. Knowledge of the differences between linear or conformational epitope is of significance in immunological applications. In a denatured protein only the linear epitope may be recognized. Hence in protocols where a denatured protein is used, such as in Western blotting, an antibody that recognizes a linear epitope is preferred. Sometimes an epitope is inside the protein. The epitope is then inaccessible to the antibody in a nondenaturing protocol, such as immunoprecipitation. A conformational epitope, by definition, must be on the outside of the folde
