Multidrug resistance protein Bmr (Bmr)

Multidrug resistance protein Bmr is a prototypical bacterial efflux pump found in Bacillus subtilis and belongs to the Major Facilitator Superfamily (MFS). It functions as a proton-drug antiporter, harnessing the energy of the transmembrane proton gradient to extrude a broad spectrum of structurally unrelated toxic substances, including antibiotics, dyes, and detergents. This efflux mechanism is a primary contributor to the multidrug resistance phenotype in bacteria, allowing them to survive in the presence of lethal concentrations of antimicrobial agents. The expression of the bmr gene is tightly regulated by the transcription factor BmrR, which undergoes a conformational change upon binding to substrates, thereby activating transcription. Bmr has been extensively studied as a model for understanding the structural basis of multidrug recognition and transport. In a therapeutic context, Bmr is a target for the development of efflux pump inhibitors (EPIs), such as the plant alkaloid reserpine, which can block the transporter and sensitize resistant bacteria to conventional antibiotics.

Other names

Multidrug resistance protein 1Multidrug-efflux transporter 1Bmr1Bacterial multidrug resistance protein

Proton-drug antiporter that utilizes the transmembrane proton gradient to actively extrude structurally diverse toxic compounds from the bacterial cell.