title: The acrAB locus is involved in modulating intracellular acetyl coenzyme A levels in a strain of Escherichia coli CM2555 expressing the chloramphenicol acetyltransferase (cat) gene.
abstract: Recently, an Escherichia coli CM2555 strain was described as sensitive to chloramphenicol when expressing the chloramphenicol resistance gene (cat) from a multicopy plasmid. This sensitivity was linked to dysfunction of the acrA gene, which encodes a component of the AcrAB-TolC multidrug efflux pump. Preliminary data indicate that the sensitivity phenotype might be due to a decline in intracellular acetyl coenzyme A concentration accompanying the reaction catalyzed by chloramphenicol acetyltransferase, the cat-encoded resistance protein. Here, we demonstrate that the acrA dysfunction is the factor impairing the intracellular acetyl coenzyme A levels in the cat-expressing CM2555 strain. This effect might be alleviated by the interplay of proteins constituting two homologous efflux systems: AcrAB-TolC and AcrEF-TolC. However, our results show also that this is a genetic background-specific phenomenon, as the decrease in acetyl coenzyme A level is not evident in a cat-bearing DeltaacrAB derivative of the commonly used strain C600.
authors: Department of Molecular Biology, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland.
authors: Joanna
authors: J
authors: Potrykus
authors: Grzegorz
authors: G
authors: Wegrzyn
mesh_terms: D000085:Acetates / Q000378:metabolism; D000105:Acetyl Coenzyme A / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001692:Biological Transport; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D002701:Chloramphenicol / Q000494:pharmacology; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics / Q000378:metabolism*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D005798:Genes, Bacterial; D008074:Lipoproteins / Q000235:genetics / Q000502:physiology*; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D026901:Membrane Transport Proteins / Q000235:genetics; D027425:ATP-Binding Cassette, Sub-Family C Proteins
chemical_list: D000085:Acetates; D000105:Acetyl Coenzyme A; D000900:Anti-Bacterial Agents; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; D002701:Chloramphenicol; D015500:Chloramphenicol O-Acetyltransferase; D029968:Escherichia coli Proteins; D008074:Lipoproteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D027425:ATP-Binding Cassette, Sub-Family C Proteins; C083497:AcrA protein, E coli; C083496:AcrB protein, E coli; C073126:tolC protein, E coli