[Recombinant Thermus thermophilus His6-DNA polymerase with reverse transcriptase activity]

The Tth DNA polymerase genes from the thermophilic bacterium Thermus thermophilus (strans HB-8 and Tt-111) were cloned and expressed in Escherichia coli cells. The target protein contained a polyhistidine tag at the N-terminus that allowed its single-stage isolation by affinity chromatography on Ni-NTA-agarose. The isolated enzyme displayed both high DNA polymerase and reverse transcriptase activities.