MONOCLONAL-ANTIBODIES PREPARED AGAINST THE DNA-POLYMERASE FROM THERMUS-AQUATICUS ARE POTENT INHIBITORS OF ENZYME-ACTIVITY

Recent interest in the unique properties of the DNA polymerase from Th ermus aquaticus (TaqPol) has stemmed from its use in many laboratories for the polymerase chain reaction. We have produced a panel of nine d istinct monoclonal antibodies to a recombinant form of TaqPol that hav e the following properties: (1) each binds TaqPol with high affinity ( K-d < 10 nM); (2) eight of the nine arbitrarily selected monoclonal an tibodies inhibit TaqPol activity completely; (3) the weak inhibitor is specific for TaqPol only while all eight strong inhibitors cross-reac t with the DNA polymerase from at least one other Thermus species as d etected by either competitive ELISA, Western blotting, inhibition of e nzyme activity or determination of binding by surface plasmon resonanc e; (4) these antibodies can be distinguished from each other by heavy chain class, cross-reactivity patterns, isoelectric points, and epitop e mapping; and (5) these antibodies define seven non-overlapping epito pes. In addition, we show data from a preliminary experiment that demo nstrates that at least one of these antibodies inhibits TaqPol by prev enting DNA binding.