The construction of new enzymes different from natural functional enzymes is
another frontier of enzyme engineering research. Catalytic antibody (also known as
abzymes) is an immunoglobulin that people give to their catalytic function. The
binding site of an antibody to an antigen is similar to that of an enzyme, but has no
catalytic activity. The enzymatic catalysis is in combination with a substrate to
produce a transition. In order to reduce energy barriers, it is envisaged to prepare a
catalytically active abzyme using a transition state analog as a hapten by an
induction method, a copy method, an insertion method, a chemical modification
method, and a genetic engineering method.