title: Studies on gene control regions X. The effect of specific adenine-thymine transversions on the lac repressor-lac operator interaction.
abstract: Chemical and enzymatic methods were used to synthesize a transition (AT to GC) and a transversion (AT to TA) at a lac operator site known to interact with lac repressor through the thymine 5 methyl group. These operators also contained a poly(dA) . poly(dT) tail 8 to 12 base pairs in length at one end. Results suggest that the steric constraints of lac repressor relative to the position of the 5 methyl group are quite critical. For example a seven fold reduction in stability was observed for the transversion. Results also suggest that the operator spans at least 21 base pairs.
mesh_terms: D000225:Adenine; D001483:Base Sequence; D004247:DNA; D004926:Escherichia coli / Q000032:analysis; D005796:Genes; D007763:Lac Operon; D009154:Mutation; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000032:analysis; D011067:Poly dA-dT; D012097:Repressor Proteins; D013941:Thymine; D014157:Transcription Factors
chemical_list: D009838:Oligodeoxyribonucleotides; D012097:Repressor Proteins; D014157:Transcription Factors; D011067:Poly dA-dT; D004247:DNA; D000225:Adenine; D013941:Thymine