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Reversion of argE3 to Arg+ in Escherichia coli AB1157 -an informative bacterial system for mutation detection

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Sikora A., Grzesiuk E.

2010

vol. 57

issue 4

479-485

This review concerns reversion of the argE3 (ochre) nonsense mutation to prototrophy in E. coli AB1157 strain as an informative system for mutation detection. Strain AB1157 bears the argE3 (ochre), hisG4 (ochre) and thr-1 (amber) mutations, and the supE44 amber suppressor on its chromosome. The Arg+ phenotype can be restored by (i) any base substitution at the argE3 site that changes the nonsense UAA codon to any sense nucleotide triplet or to UAG recognized by the supE44 amber suppressor, or (ii) suppressor mutations enabling the reading of the UAA nonsense codon. The argE3 → Arg+ reversion-based system enables (i) determination of the spontaneous or induced mutation level; (ii) determination of base substitutions (suppressor analysis); (iii) examination of transcription-coupled repair (TCR) since targets for DNA damage are situated on the transcribed or coding strand of DNA; (iv) detection of mutations resulting from single stranded DNA damage. This review focuses on studies carried out since the early 1990s till now with the application of the AB1157-based mutation detection system. Recently, the system has been used to obtain new data on the processes of methyl methanesulfonate-induced mutagenesis and DNA repair in E. coli alkB- mutants.

Reversion of argE3 ochre strain Escherichia coli AB1157 as a tool for studying the stationary-phase (adaptive) mutations.

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Nowosielska A., Grzesiuk E.

2000

vol. 47

issue 2

459-467

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.

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2 Acta Biochimica Polonica

1 2010

1 2000

2 Grzesiuk E.

1 Nowosielska A.

1 Sikora A.

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Reversion of argE3 to Arg+ in Escherichia coli AB1157 -an informative bacterial system for mutation detection

Reversion of argE3 ochre strain Escherichia coli AB1157 as a tool for studying the stationary-phase (adaptive) mutations.