Recent advances in understanding microbial regulation of host multi-drug resistance transporters

Multi-drug resistance transporters are highly conserved proteins present in both eukaryotic and prokaryotic organisms. They are responsible for controlling physiologic efflux of toxins or xenobiotics from the cell as a form of protection which may also render the cells resistant to therapeutics. However, researchers have recently identified endogenous substrates of these transporters that modulate inflammation in addition to overall cell and organ function. While changes in the expression of these transporters have been implicated in some human diseases, it is becoming appreciated that such expression can also be regulated by microbes in both settings of health and during infection. Bacteria and viruses can be pathogenic or live in a symbiotic relationship as in commensal microbiota. Our objective is to highlight recent examples of microbial regulation of multi-drug resistance transporters in the mammalian host from the perspective of how this co-evolving relationship can negatively as well as positively impact the host.