Abstract: The present invention provides a GG-specific mismatch endonuclease variant, a TT-specific mismatch endonuclease variant, and a GT/TG-specific mismatch endonuclease variant. The present invention also provides a mismatch specific cleaving reaction using said variant, a method for removing errors in a nucleic acid amplification reaction using a mismatch nuclease, a method for suppressing amplification of a nucleic acid having a specific base sequence during a nucleic acid amplification reaction, and a method for detecting a nucleic acid having a single base polymorphic mutation using said suppression method.

Abstract: The present invention relates to a method for detecting a target nucleic acid, the method including cleaving a first flap of a first cleavage structure formed by a target nucleic acid, a first nucleic acid, and a second nucleic acid; cleaving a second flap of a second cleavage structure formed by a third nucleic acid, the cleaved first flap, and a fourth nucleic acid; and detecting the presence of the target nucleic acid by detecting the cleaved second flap, wherein cleaving the first flap and cleaving the second flap are carried out by cleaving the first flap and the second flap with a flap endonuclease, and the flap endonuclease has an amino acid sequence having a sequence identity of 65% or higher with an amino acid sequence of a flap endonuclease of a microbe selected from the group consisting of microbes belonging to the Order Thermococcales and microbes belonging to the Order Methanobacteriales.

Abstract: The present invention relates to a method for detecting a target nucleic acid, the method including cleaving a first flap of a first cleavage structure formed by a target nucleic acid, a first nucleic acid, and a second nucleic acid; cleaving a second flap of a second cleavage structure formed by a third nucleic acid, the cleaved first flap, and a fourth nucleic acid; and detecting the presence of the target nucleic acid by detecting the cleaved second flap, wherein cleaving the first flap and cleaving the second flap are carried out by cleaving the first flap and the second flap with a flap endonuclease, and the flap endonuclease has an amino acid sequence having a sequence identity of 96% or higher with an amino acid sequence of a flap endonuclease of Thermococcus kodakarensis strain KOD1, or the like.

Abstract: The present invention relates to a Thermus aquaticus (Taq) polymerase having a strand displacement activity in which an amino acid residue in a template DNA binding site of the DNA polymerase is substituted with an amino acid to increase a total charge in the site, a nucleic acid encoding the polymerase, a vector containing the nucleic acid, a transformant containing the vector containing the nucleic acid or the nucleic acid, a method for producing the polymerase, a method for amplifying nucleic acids utilizing the polymerase, and a kit containing the polymerase. According to the present invention, a DNA polymerase having a high thermostability, capable of efficiently replicating a long-strand of a template DNA, and having a strong strand displacement activity is provided.

Abstract: A polypeptide having a mismatch endonuclease activity of recognizing a mismatch and cleaving the mismatch; a mismatch-specific cleavage reaction using the polypeptide; a method for removing an error in a nucleic acid amplification reaction utilizing the polypeptide; a method for inhibiting the amplification of a nucleic acid comprising a specific nucleotide sequence during a nucleic acid amplification reaction; and a method for detecting a nucleic acid having a single-nucleotide polymorphism mutation utilizing the inhibition method.

Abstract: The present invention relates to a fusion polypeptide containing, in a direction of from an N-terminal side to a C-terminal side, one or more peptides which bind to a PCNA, and a polypeptide having a DNA polymerase activity; a method for amplifying nucleic acids using the polypeptide; and a composition and a kit, containing the polypeptide. According to the present invention, it is made possible to amplify a long-strand DNA in a short time in amplifying nucleic acids in the presence of PCNA even with a Pol I-type DNA polymerase.

Abstract: The present invention relates to a Thermus aquaticus (Taq) polymerase having a strand displacement activity in which an amino acid residue in a template DNA binding site of the DNA polymerase is substituted with an amino acid to increase a total charge in the site, a nucleic acid encoding the polymerase, a vector containing the nucleic acid, a transformant containing the vector containing the nucleic acid or the nucleic acid, a method for producing the polymerase, a method for amplifying nucleic acids utilizing the polymerase, and a kit containing the polymerase. According to the present invention, a DNA polymerase having a high thermostability, capable of efficiently replicating a long-strand of a template DNA, and having a strong strand displacement activity is provided.

Abstract: There is provided an enzyme which has an activity of cleaving a phosphodiester bond of deoxyribonucleotide having a damaged base and deoxyribonucleotide adjacent to the 5? side of the deoxyribonucleotide in DNA strands which contain the damaged base as a reagent or the like for manipulating a gene, and further provided a method of removing a damaged base from DNA strands using the enzyme.

Abstract: A polypeptide having a mismatch endonuclease activity of recognizing a mismatch and cleaving the mismatch; a mismatch-specific cleavage reaction using the polypeptide; a method for removing an error in a nucleic acid amplification reaction utilizing the polypeptide; a method for inhibiting the amplification of a nucleic acid comprising a specific nucleotide sequence during a nucleic acid amplification reaction; and a method for detecting a nucleic acid having a single-nucleotide polymorphism mutation utilizing the inhibition method.

Abstract: There is provided an enzyme which has an activity of cleaving a phosphodiester bond of deoxyribonucleotide having a damaged base and deoxyribonucleotide adjacent to the 5? side of the deoxyribonucleotide in DNA strands which contain the damaged base as a reagent or the like for manipulating a gene, and further provided a method of removing a damaged base from DNA strands using the enzyme.