The present invention relates to DNA polymerases. In particular the invention relates to a method for the generation of DNA polymerases exhibiting a relaxed substrate specificity. Uses of mutant polymerases produced using the methods of the invention are also described.
1. An isolated pol A DNA polymerase having at least 95% identity to the amino acid sequence of SEQ ID NO:86, wherein said pol A DNA polymerase is capable of abasic site bypass and has an expanded substrate range relative to a wild type polA DNA polymerase selected from the group consisting of Taq, Tth and Tfl, and wherein said pol A DNA polymerase comprises the following amino acids at the following positions: K at position 76, Q at position 90, G at position 144, Q at position 335, T at position 447, M at position 615, M at position 738 and G at position 743 with reference to the amino acid positions of SEQ ID NO:86.
2. The isolated pol A DNA polymerase of claim 1 , wherein said pol A DNA polymerase comprises the amino acid sequence of SEQ ID NO:86.
3. The isolated pol A DNA polymerase of claim 2 , wherein said DNA polymerase consists of the amino acid sequence of SEQ ID NO:86.
4. The isolated pol A DNA polymerase of claim 1 , wherein said pol A DNA polymerase comprises a 5′-3′ exonuclease domain which is derived from Tth.
5. An isolated pol A DNA polymerase having at least 95% identity to the amino acid sequence of SEQ ID NO:86, wherein said pol A DNA polymerase is capable of abasic site bypass, and has an expanded substrate range relative to a polymerase consisting of the amino acid sequence of SEQ ID NO: 1, and wherein said pol A DNA polymerase comprises the following amino acids at the following positions: K at position 76, Q at position 90, G at position 144, Q at position 335, T at position 447, M at position 615, M at position 738 and G at position 743 with reference to the amino acid positions of SEQ ID NO: 86.