Multidrug efflux pumps and their rules in plant associated bacteria

Plant Associated Bacteria are one of the most important elements of plant ecosystems. These bacteria live internally (endophytes) or externally (epiphytes) in different plants organs and have various effects on the life cycle of plants. These bacteria are constantly exposed to different antibacterial compounds which are secreted from plants and other epiphytic microorganisms in their natural habitat. Plant-associated bacteria deal with these toxic compounds in a variety of ways, one of which is the use of efflux systems. An active efflux mechanism is responsible for the transportation of antibacterial compounds out of the cell. This process is associated with energy consumption which is provided from ATP hydrolysis or electrochemical gradient. These pumps are protein vectors that express from chromosome or plasmid and not only have critical rule in drug resistance, also have other physiological proceeds. The rule of efflux systems in plant-associated bacteria and their relation with transcription regulatory are discuss in this article.