A sensitive method for identification of DNA dependent DNA polymerases in acrylamide gels after seperation by micro disc electrophoresis.

Two sensitive methods are described for detection of DNA dependent DNA polymerase activities in polyacrylamide gels after their fractionation by micro-disc electrophoresis. One technique is based on the increase in fluorescence of the ethidium bromide complex with template polydeoxyribonucleotides brought about by the action of the polymerases. The sensitivity of the previously described technique has been enhanced. Another method, 14 fold as sensitive, uses radioactive precursors in the enzyme assay after electrophoretic separation; washing, slicing and counting allows to evaluate incorporation into acid insoluble polymer, requiring 3* 10“ 2 units corresponding to approx. 0.02 /ug of E. coli DNA polymerase I preparation. Differing activities of polymerase species and differing template preferences may be investigated with these techniques.