Antibiotics & Resistance: bacterial multidrug resistance and photoactivatable antibiotics

Antibiotic resistance in bacteria is becoming a major threat for public health. Bacteria can use several ways to evade the toxic effect of antibiotics and one of these is by pumping the drugs out of the cell. This research investigated the involvement of such transport proteins in antibiotics and multidrug resistance. A select set of predicted antibiotic efflux pumps from the human pathogenic bacterium Staphylococcus aureus was characterized for their role in resistance, but none of these proteins could be associated with this phenomenon. Likely, these transporters fulfill other export functions in the cell.
The regulation of expression of multidrug transporters via the regulatory protein LmrR was studied in the lactic acid bacterium Lactococcus lactis. This bacterium carries the efflux pump LmrCD, which is controlled by the regulatory protein LmrR. We could show that LmrR can bind to specific DNA regions to control production of both LmrCD and itself, and that binding of substrate affects the LmrR-DNA binding.
Another way to counteract antibiotics resistance, is the incorporation of a light activated switch into the antibiotic to control the antibacterial activity. Also, the introduction of a photoswitch into signal molecules, which are used by bacteria to communicate, allowed us to control cellular processes such as virulence development. This shows the potential application of photoswitches in the control of infectious disease.