Drug efflux

Drug efflux is a mechanism that removes toxic substances and antibiotics from the cell. This process is an important factor in drug resistance of bacteria and can affect treatment outcomes in patients.

Mechanism of Drug Efflux

Drug efflux is a process that is facilitated by efflux pumps. These are proteins that are located in the cell membrane and function to remove unwanted substances from the cell. The process of drug efflux can be divided into three steps: drug uptake, drug binding, and drug expulsion.

Drug Uptake

The first step in drug efflux is the uptake of the drug into the cell. This can occur through passive diffusion or through active transport. In passive diffusion, the drug moves across the cell membrane from an area of high concentration to an area of low concentration. In active transport, the drug is moved against its concentration gradient, which requires energy in the form of adenosine triphosphate (ATP).

Drug Binding

Once inside the cell, the drug binds to the efflux pump. The binding of the drug triggers a change in the conformation of the pump, which prepares it for the next step of the process.

Drug Expulsion

The final step in drug efflux is the expulsion of the drug from the cell. This is also an active process that requires energy. The energy is used to change the conformation of the efflux pump, which allows the drug to be expelled from the cell.

Role in Drug Resistance

Drug efflux is a major mechanism of drug resistance in bacteria. By expelling antibiotics from the cell, bacteria can survive in the presence of these drugs and continue to multiply. This can lead to the development of multidrug resistance, which is a serious problem in the treatment of bacterial infections.

See Also

• Efflux pump
• Drug resistance
• Multidrug resistance