UMass Chan Affiliations
Department of Biochemistry and Molecular PharmacologyDocument Type
Journal ArticlePublication Date
2012-03-15Keywords
Antibiotics, AntineoplasticBacterial Proteins
Bleomycin
Culture Media
DNA Breaks, Double-Stranded
DNA Ligases
DNA Restriction Enzymes
DNA, Bacterial
DNA-(Apurinic or Apyrimidinic Site) Lyase
Drug Resistance, Bacterial
Escherichia coli K12
Escherichia coli Proteins
Genes, Bacterial
Mutation
Oligonucleotide Array Sequence Analysis
RNA, Bacterial
Recombinational DNA Repair
SOS Response (Genetics)
Biochemistry, Biophysics, and Structural Biology
Life Sciences
Medicine and Health Sciences
Metadata
Show full item recordAbstract
Bleomycin (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.Source
Xu 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 siteDOI
10.1371/journal.pone.0033256Permanent Link to this Item
http://hdl.handle.net/20.500.14038/39544PubMed ID
22438905Related Resources
Link to Article in PubMedRights
Copyright: © 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.ae974a485f413a2113503eed53cd6c53
10.1371/journal.pone.0033256
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