Molecular and General Genetics MGG

, Volume 215, Issue 1, pp 161–164 | Cite as

The isolation and preliminary characterisation of a novel Escherichia coli mutant rorB with enhanced sensitivity to ionising radiation

  • Paul G. Debenham
  • Michael B. T. Webb


Escherichia coli K803 cells were mutagenized and screened for the presence of clones sensitive to ψ-rays but not to ultraviolet light. One new mutant of this type, named rorB, was isolated. This mutant is both cross-sensitive to mitomycin C and shows reduced conjugal recombination frequencies, but to a lesser extent than the phenotypically similar mutant recN. Unlike previously reported mutants of E. coli or yeast with an enhanced sensitivity to ionising radiations, rorB appears to be near wild type in ability to rejoin DNA double-strand breaks. The rorB gene maps close to ilvGEDAC at 84.5 min of the E. coli chromosome.

Key words

Escherichia coli Ionising radiation Mutation DNA repair 


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Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • Paul G. Debenham
    • 1
  • Michael B. T. Webb
    • 1
  1. 1.Division of Cell and Molecular BiologyMRC Radiobiology UnitDidcotUK

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