Related Experiment Video
Updated: Jun 24, 2026

Expression, Detergent Solubilization, and Purification of a Membrane Transporter, the MexB Multidrug Resistance Protein
Published on: December 3, 2010
Assembly and transport mechanism of tripartite drug efflux systems
Rajeev Misra1, Vassiliy N Bavro
1Faculty of Cellular and Molecular Biosciences, School of Life Sciences, Arizona State University, Tempe, AZ 85285-4501, USA. rajeev.misra@asu.edu
Abstract:
Multidrug efflux (MDR) pumps remove a variety of compounds from the cell into the external environment. There are five different classes of MDR pumps in bacteria, and quite often a single bacterial species expresses multiple classes of pumps. Although under normal circumstances MDR pumps confer low-level intrinsic resistance to drugs, the presence of drugs and mutations in regulatory genes lead to high level expression of MDR pumps that can pose problems with therapeutic treatments. This review focuses on the resistance nodulation cell division (RND)-class of MDR pumps that assemble from three proteins. Significant recent advancement in structural aspects of the three pump components has shed new light on the mechanism by which the tripartite efflux pumps extrude drugs. This new information will be critical in developing inhibitors against MDR pumps to improve the potency of prescribed drugs.
More Related Videos
Related Concept Videos
Carrier-Mediated Transport
Active transport involves two types of membrane-spanning transporters: uptake and efflux. Uptake transporters are expressed in the small...
Drug Absorption Mechanism: Carrier-Mediated Membrane Transport
Facilitated diffusion is a passive process that utilizes human Solute Carrier (SLC) transporters. These transporters bind to the drug, undergo structural...
Mechanisms of Drug Absorption: Paracellular, Transcellular, and Vesicular Transport
However, most drugs use the transcellular route, traversing directly through the cell membranes via two mechanisms: passive and active transport. Passive...
ABC Transporters: Exporter
Cellular Membranes and Drug Transport
Phospholipids arrange themselves into a bilayer, with hydrophilic heads oriented outward and hydrophobic tails facing inward.
Membrane Transporters
Transporters are mainly composed of alpha-helices, built from bundles of ten or more helices traversing the plasma membrane. The solute-binding sites are located midway, where some of the helices are broken or distorted, making space for the binding site through...

