DNA POLYMERASES WITH ENHANCED THERMOSTABILITY AND ENHANCED LENGTH AND EFFICIENCY OF PRIMER EXTENSION

摘要

A DNA polymerase having an amino acid sequence comprising substantially the same amino acid sequence as that of Thermusaquaticus or Thermus flavus DNA polymerase, excluding the N-terminal 280 amino acid residues of Thermus aquaticus DNA polymerase orthe N-terminal 279 amino acid residues of Thermus flavus DNA polymerase, recombinant DNA sequences encoding said DNA polymerases,vectors comprising said DNA sequences, and host cells containing such vectors. A formulation of thermostable or other DNA polymerasescomprising a majority component comprised of at least one thermostable or other DNA polymerase of the type described above, whereinthe DNA polymerase lacks 3'-exonuclease activity, and a minority component comprised of at least one thermostable DNA polymeraseexhibiting 3'-exonuclease activity, and an improved method for enzymatic extension of DNA strands, especially while, but not limitedto, amplifying nucleic acid sequences by polymerase chain reaction wherein the above formulation is made and used to catalyse primerextension, are also provided.