QacA multidrug efflux pump from Staphylococcus aureus: comparative analysis of resistance to diamidines, biguanidines, and guanylhydrazones.
نویسندگان
چکیده
The staphylococcal multidrug efflux pump QacA mediates resistance to a broad spectrum of monovalent and divalent antimicrobial cations. Resistance toward various classes of these compounds identified features of the substrate that may be important for interaction with QacA. Analysis of combinations of two substrates suggested that the same mechanism is used for the extrusion of different classes of compounds.
منابع مشابه
Low-level resistance of Staphylococcus aureus to thrombin-induced platelet microbicidal protein 1 in vitro associated with qacA gene carriage is independent of multidrug efflux pump activity.
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The closely related multidrug efflux pumps QacA and QacB, from the bacterial pathogen Staphylococcus aureus, both confer resistance to various toxic organic cations but differ in that QacB mediates lower levels of resistance to divalent cations. Cloning and nucleotide sequencing of the qacB gene revealed that qacB differs from qacA by only seven nucleotide substitutions. Random hydroxylamine mu...
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 42 2 شماره
صفحات -
تاریخ انتشار 1998