title: Specific deletion of DNA sequences between preselected bases.
abstract: Blunt-end ligation of a "filled-in" HindIII, Sal I, Ava I or Bcl I restriction site with a DNA fragment having A, G, C, or T as the terminal 3' nucleotide regenerates the corresponding restriction site. A combination of this property with the action of BAL 31 nuclease which progressively removes base-pairs from the ends of linear DNA, can generate deletions extending to desired pre-selected nucleotides, and introduces unique restriction sites at those positions. Similarly other restriction sites can be used to select for the deletion of sequences between specific di-, tri-, tetra- and penta-nucleotides. Using this method, 10 base pairs were deleted from the end of a restriction fragment carrying the late promoter for bacteriophage T7 gene 1.1, to create a molecule with a unique restriction site at the initiation codon for translation.
mesh_terms: D001483:Base Sequence; D004262:DNA Restriction Enzymes; D004274:DNA, Recombinant; D005814:Genes, Viral; D010957:Plasmids; D013604:T-Phages / Q000235:genetics*
chemical_list: D004274:DNA, Recombinant; D004262:DNA Restriction Enzymes