title: Study of MFD-type repair in locus determining resistance of Escherichia coli to streptomycin.
abstract: The yield of induced mutations to streptomycin resistance (Str) in E. coli, UV-irradiated and temporarily incubated in liquid medium not permitting protein synthesis, depends upon the conditions of preirradiation growth and preirradiation treatment of the bacteria, i.e. on their physiological state at the moment of irradiation. This fact is not readily reconciled with a model postulating mutation production in the structural genes of E. coli during excision repair. A preferred explanation is offered, based on the assumption that the efficiency of mutagenesis at the rpsL (strA) locus is determined by interference of antimutagenic (generalized excision repair and MFD) and promutagenic (mutation fixation of excision repair) events. The participation of macromolecular syntheses in Str mutation fixation is suggested.
mesh_terms: D004260:DNA Repair; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000528:radiation effects; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial / Q000528:radiation effects*; D009154:Mutation; D000091243:Ribosomal Protein S9; D013307:Streptomycin / Q000494:pharmacology*; D014466:Ultraviolet Rays
chemical_list: D029968:Escherichia coli Proteins; D000091243:Ribosomal Protein S9; C000717190:RpsI protein, E coli; D013307:Streptomycin