Efflux pumps

Definition

Efflux pumps are membrane proteins that actively export harmful substances out of microbial cells, contributing to antibiotic resistance. They play a crucial role in maintaining cellular homeostasis by removing toxic compounds.

5 Must Know Facts For Your Next Test

1. Efflux pumps can transport a wide variety of substrates including antibiotics, heavy metals, and detergents.
2. They contribute significantly to multidrug resistance (MDR) in bacteria by expelling multiple types of antibiotics.
3. Efflux pumps are powered by ATP or the proton motive force, depending on their specific type.
4. Genes encoding efflux pumps can be located on both chromosomal DNA and plasmids, facilitating horizontal gene transfer.
5. Inhibiting efflux pump activity is a potential strategy for overcoming antibiotic resistance.

Review Questions

• What is the primary function of efflux pumps in microbial cells?
• How do efflux pumps contribute to antibiotic resistance?
• What are two energy sources that power efflux pumps?

Related terms

Plasmid:

A small DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently.

Multidrug Resistance (MDR): The ability of microorganisms to resist the effects of multiple antimicrobial drugs.

Proton Motive Force:

The force generated across a cell membrane used to drive processes such as ATP synthesis and active transport mechanisms like efflux pumps.