The plasma cell will, in turn, basically begin building antibodies that contain an active side that has a complementary structure to this particular antigen. And so, once we build that antibody, the antibody will be easily able to fit those protoporphrine molecules into the antibody active side. And that antibody will, in turn, have the catalytic ability to basically transform or insert that se atom into the centering of that particular protoporphine. So we see that transition state analogs are not only useful in actually inhibiting and blocking the ability of enzymes to catalyze reactions, but we can also use these transition state analogues to actually build antibodies that have catalytic capabilities. And these antibodies are commonly known as enzymes, where AB stands for antibody and the zine part stands for the enzyme. So, abzymes are these antibodies that contain catalytic capabilities that can basically catalyze their different types of reactions.