| 摘要 |
This invention provides a DNA polymerase that is a mutant form of a naturally occurring DNA polymerase, of which one or more amino acids in the active site are mutated. The DNA polymerase mutant of this invention is characterized by altered fidelity or altered enzymatic activity in comparison with the naturally occurring DNA polymerase. For example, the DNA polymerase mutant provides increased enzymatic activity, altered dNTP/rNTP specificity, or enhanced fidelity. In one aspect of the invention, the naturally occurring DNA polymerase comprises an amino acid sequence motif: AspTyrSerGlnIleGluLeuArg in the active site. In another aspect of the invention, the naturally occurring DNA polymerase comprises an amino acid sequence motif: LeuLeuVa1AlaLeuAspTyrSerGlnIleGluLeuArg in the active site. The mutant DNA polymerase has been altered in the active site of the naturally occurring DNA polymerase to contain either (a) two or more amino acid substitutions in the amino acid sequence motif, or (b) a substitution of an amino acid other than Glu in the amino acid sequence motif. |
