Reversion of argE3 ochre strain Escherichia coli AB1157 as a tool for studying the stationary-phase (adaptive) mutations.
Adaptive (starvation-associated) mutations occur in non-dividing cells and allow growth under the selective conditions imposed. We developed a new method for the determination of adaptive mutations in Escherichia coli. The system involves reversion to prototrophy of the argE3OC mutation and was tested on AB1157 strains mutated in the mutT and/or mutY genes. The bacteria that mutated adaptively grow into colonies on minimal medium plates devoid of arginine (starvation conditions) when incubated longer than 4 days. Using the replica plating method we solved the problem of discrimination between growth-dependent and adaptive argE3-->Arg+ revertants. Phenotype analysis and susceptibility of the Arg+ revertants to a set of T4 phage mutants create an additional possibility to draw a distinction between these two types of Arg+ revertants.
Nowosielska
A
A
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa.
Grzesiuk
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E
D000222:Adaptation, Physiological / Q000502:physiology*; D001120:Arginine / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics*; D003470:Culture Media; D045647:DNA Glycosylases; D004260:DNA Repair; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development; D029968:Escherichia coli Proteins; D007700:Kinetics; D016296:Mutagenesis; D009699:N-Glycosyl Hydrolases / Q000235:genetics*; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics*; D011755:Pyrophosphatases; D013997:Time Factors
D001426:Bacterial Proteins; D003470:Culture Media; D029968:Escherichia coli Proteins; D001120:Arginine; D010744:Phosphoric Monoester Hydrolases; D045647:DNA Glycosylases; D009699:N-Glycosyl Hydrolases; C061738:mutY adenine glycosylase; D011755:Pyrophosphatases; C052211:mutT protein, E coli