Sánchez Díaz P
Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnologia (CSIC), Campus Universidad Autonoma de Madrid, Cantoblanco, Madrid, Spain.
Rev Esp Quimioter. 2003 Jun;16(2):172-87.
The term MDR (Multi Drug Resistance) system refers to a group of transporters which are able to expulse a wide range of quite different substrates. While this type of system was first described in eukaryotic cells in the late 1980s, the presence of MDR efflux-pumps in bacteria showing resistance to several drugs has been increasingly reported in the literature. Under laboratory conditions the expression of these MDR systems is usually down-regulated. On occasion, basal expression of these efflux pumps is allowed in wild type strains, thus suggesting a role of these MDR systems in the intrinsic of these microorganisms resistance to antibiotics. On the other hand, overexpression of these MDR efflux pumps, after induction or because of the emergence of mutations in their regulatory elements, is also important in acquired resistance to antibiotics. This review summarizes the most relevant features of the MDR systems described in bacteria, as well as the mechanisms that regulate their expression.
术语“多重耐药（MDR）系统”指的是一组能够排出多种截然不同底物的转运蛋白。虽然这类系统在20世纪80年代末首次在真核细胞中被描述，但文献中越来越多地报道了细菌中存在对多种药物具有抗性的MDR外排泵。在实验室条件下，这些MDR系统的表达通常会下调。有时，野生型菌株中这些外排泵会有基础表达，这表明这些MDR系统在这些微生物对抗生素的固有抗性中发挥作用。另一方面，在诱导后或由于其调控元件发生突变而导致这些MDR外排泵过度表达，在获得性抗生素抗性中也很重要。本综述总结了细菌中描述的MDR系统的最相关特征以及调节其表达的机制。
