Bacteria use a number of mechanisms to defend themselves from antimicrobial drugs. One important defense strategy is the ability to export drugs by multidrug transporters. One class of multidrug transporter, the so-called multidrug and toxic compound extrusion (MATE) transporters, extrude a variety of antibiotic compounds from the bacterial cytoplasm. These MATE transporters are driven by a Na+, H+, or combined Na+/H+ gradient, and act as antiporters to drive a conformational change in the transporter from the outward to the inward-facing conformation. In the inward-facing conformation, a chemical compound (drug) binds to the protein, resulting in a switch to the opposite conformation, thereby extruding the drug. Using molecular dynamics simulations, we now report the structural basis for Na+ and H+ binding in the dual ion coupled MATE transporter ClbM from Escherichia coli, which is connected to colibactin-induced genotoxicity, yielding novel insights into the ion/drug translocation mechanism of this bacterial transporter.

中文翻译：

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关于MATE转运蛋白ClbM的离子耦合机理。

细菌使用多种机制来保护自己免受抗菌药物的侵害。一种重要的防御策略是多药运输者出口毒品的能力。一类多药转运蛋白，即所谓的多药和有毒化合物挤出（MATE）转运蛋白，从细菌细胞质中挤出了多种抗生素化合物。这些MATE转运蛋白由Na +，H +或组合的Na + / H +梯度驱动，并充当反向转运蛋白，以驱动转运蛋白的构象变化，从外向内向内。在向内构象中，化合物（药物）与蛋白质结合，导致转换为相反构象，从而挤出了药物。使用分子动力学模拟，