title: Mutational specificity of the base analogue, 2-aminopurine, in Escherichia coli.
abstract: 2-Aminopurine (2-AP) is a base analogue of adenine which mispairs with cytosine and causes base-pair substitutions of the transition type. By analyzing the reversion patterns of defined trpA alleles in Escherichia coli we confirm that 2-AP causes both A:T leads to G:C and G:C leads to A:T transitions with the former induced more frequently than the latter. We also find that 2-AP enhances transversions at 3 sites and frameshift mutations at 1 other site. It is unlikely that 2-AP can cause transversions and frameshifts solely by a mispairing mechanism. However, 2-AP-induced transversion and frameshift mutagenesis was not abolished by the presence of an inactive recA allele, indicating this mutagenic activity is not dependent upon recA-directed misrepair.
mesh_terms: D015075:2-Aminopurine / Q000494:pharmacology*; D000225:Adenine / Q000031:analogs & derivatives*; D004926:Escherichia coli / Q000235:genetics*; D009153:Mutagens / Q000494:pharmacology; D009154:Mutation / Q000187:drug effects*; D011995:Recombination, Genetic; D014161:Transduction, Genetic
chemical_list: D009153:Mutagens; D015075:2-Aminopurine; D000225:Adenine