UMass Chan AffiliationsDepartment of Biochemistry and Molecular Pharmacology
DNA Breaks, Double-Stranded
DNA Restriction Enzymes
DNA-(Apurinic or Apyrimidinic Site) Lyase
Drug Resistance, Bacterial
Escherichia coli K12
Escherichia coli Proteins
Oligonucleotide Array Sequence Analysis
Recombinational DNA Repair
SOS Response (Genetics)
Biochemistry, Biophysics, and Structural Biology
Medicine and Health Sciences
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AbstractBleomycin (BLM) is a glycopeptide antibiotic and anti-tumor agent that targets primarily the furanose rings of DNA and in the presence of ferrous ions produces oxidative damage and DNA strand breaks. Escherichia coli cells growing in broth medium and exposed to low concentrations of BLM contain double-strand breaks and require homologous recombination to survive. To a lesser extent, the cells also require the abasic (AP) endonucleases associated with base excision repair, presumably to repair oxidative damage. As expected, there is strong induction of the SOS system in treated cells. In contrast, E. coli cells growing in glucose or glycerol minimal medium are resistant to the lethal action of BLM and do not require either homologous recombination functions or AP-endonucleases for survival. DNA ligase activity, however, is needed for cells growing in minimal medium to resist the lethal effects of BLM. There is weak SOS induction in such treated cells.
SourceXu T, Brown W, Marinus MG (2012) Bleomycin Sensitivity in Escherichia coli is Medium-Dependent. PLoS ONE 7(3): e33256. doi:10.1371/journal.pone.0033256. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/39544
Related ResourcesLink to Article in PubMed
RightsCopyright: © 2012 Xu et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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