What are drug efflux transporters?
All cells express efflux transporters that protect them from endogenous or exogenous toxic substances18. Most of these transporters belong to the superfamily of ATP-binding cassette (ABC) proteins, which drive the cellular extrusion of many therapeutic drugs with different structures and clinical uses.
How do efflux transporters affect the bioavailability of the drugs?
Efflux Transporters in the Intestine In the intestine, drug-transporter interactions involving the efflux transporters often result in poor absorption and low oral bioavailability as the drug is readily effluxed back into the intestinal lumen and excreted out of the body.
What does efflux mean in biology?
Efflux is the process in which bacteria transport compounds outside the cell which are potentially toxic, such as drugs or chemicals or compounds.
What is efflux and influx?
Movement of ions into cells is called influx while movement of ions out of the cells is called efflux.
What do efflux transporters do?
These proteins are commonly referred to as multidrug or efflux transporters. They provide important protection in all organisms. In humans, for example, they are active in the blood–brain barrier, intestines, liver, kidney, and placenta.
How do efflux pump inhibitors work?
Antibiotic efflux is one of the major mechanisms, whereby bacteria pump out the antibiotics from their cellular interior to the external environment using special transporter proteins called efflux pumps. Inhibiting these pumps seems to be an attractive strategy at a time when novel antibiotic supplies are dwindling.
What is role of efflux pump in antibiotic resistance?
Drug efflux is a key mechanism of resistance in Gram-negative bacteria. These systems pump solutes out of the cell. Efflux pumps allow the microorganisms to regulate their internal environment by removing toxic substances, including antimicrobial agents, metabolites and quorum sensing signal molecules.
What is active efflux?
Active efflux is a common resistance mechanism in a wide range of bacterial pathogens. It is responsible for the transport of such toxic compounds as drugs, toxins, and detergents. The transport is effectively regulated by local regulatory proteins.
What does membrane potential do?
First, it allows a cell to function as a battery, providing power to operate a variety of “molecular devices” embedded in the membrane. Second, in electrically excitable cells such as neurons and muscle cells, it is used for transmitting signals between different parts of a cell.
How does an efflux pump cause antibiotic resistance?
How does active efflux work?
Efflux systems function via an energy-dependent mechanism (active transport) to pump out unwanted toxic substances through specific efflux pumps. Some efflux systems are drug-specific, whereas others may accommodate multiple drugs with small multidrug resistance (SMR) transporters.