MONOCLONAL-ANTIBODY RECOGNIZES DIFFERENT QUINONE MOIETIES IN ENZYMES

We produced monoclonal antibodies against the coenzyme pyrrolequinolin e quinone (PQQ). These antibodies were obtained by immunizing mice wit h PQQ conjugated to a chemically modified polypeptide in order to indu ce a strong immune response. Among the various antibodies obtained, on e was found to bind (besides PQQ and 6-hydroxydopamine conjugated to c arrier proteins) several different quinoenzymes, namely lentil seedlin g and bovine serum diamine oxidases and methylamine dehydrogenase. Thi s antibody was able to inhibit the catalytic activity of these enzymes . Moreover, the monoclonal antibody recognized different proteins of l entil seeds on Western blots. Even the variable fragment of immunoglob ulin heavy chains of this monoclonal antibody expressed in Escherichia coli is able to recognize the active site of different quinoenzymes.