MmpL3 a potential new target for development of novel anti-tuberculosis drugs.

INTRODUCTION: Tuberculosis (TB) is still a leading cause of mortality in the developing world and there is an unmet clinical need for new drugs with novel mechanism of action. Targeting the complex and unique cell wall of TB-causing pathogen Mycobacterium tuberculosis (Mtb) has been a mainstay of TB drug discovery. Though, the composition of the cell wall of Mtb is well understood, little is known about the assembly process of the cell wall such as the transport of mycolic acids across the cell wall. AREAS COVERED: Recent research demonstrating MmpL3 protein as a transmembrane transporter of mycolic acids is discussed. In addition, MmpL3 has also been implicated in heme transport. Research describing several diverse chemical inhibitors that inhibit MmpL3 is reviewed. EXPERT OPINION: Evidence so far suggests MmpL3 is a transporter of mycolic acids. It has emerged as a novel therapeutic target for Mtb that is essential and for which several small molecule inhibitors have been identified. Identifying the interacting partners, understanding the substrate specificity and the mechanism of transport by MmpL3 are some of the gaps in knowledge that need to be addressed.