title: Structure-specific endonucleolytic cleavage of nucleic acids by eubacterial DNA polymerases.
abstract: Previously known 5' exonucleases of several eubacterial DNA polymerases have now been shown to be structure-specific endonucleases that cleave single-stranded DNA or RNA at the bifurcated end of a base-paired duplex. Cleavage was not coupled to synthesis, although primers accelerated the rate of cleavage considerably. The enzyme appeared to gain access to the cleavage site by moving from the free end of a 5' extension to the bifurcation of the duplex, where cleavage took place. Single-stranded 5' arms up to 200 nucleotides long were cleaved from such a duplex. Essentially any linear single-stranded nucleic acid can be targeted for specific cleavage by the 5' nuclease of DNA polymerase through hybridization with an oligonucleotide that converts the desired cleavage site into a substrate.
authors.affiliation: Department of Biomolecular Chemistry, University of Wisconsin School of Medicine, Madison 53706.
authors.forename: V
authors.initials: V
authors.lastname: Lyamichev
authors.forename: M A
authors.initials: MA
authors.lastname: Brow
authors.forename: J E
authors.initials: JE
authors.lastname: Dahlberg
mesh_terms: D001483:Base Sequence; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000378:metabolism*; D012313:RNA / Q000378:metabolism*; D019914:Taq Polymerase; D013698:Templates, Genetic
chemical_list: D004277:DNA, Single-Stranded; D009838:Oligodeoxyribonucleotides; D012313:RNA; C072146:Pfu DNA polymerase; D019914:Taq Polymerase; C070331:Tli polymerase; C068508:Tth polymerase; D004259:DNA-Directed DNA Polymerase