Inhibition of Protein-protein Interactions in Mycobacterium tuberculosis

Abstract

Tuberculosis is a highly contagious, infectious disease that kills about 1.8 million people annually. Current chemotherapeutic regimens are both inefficient and taxing to the patient. In addition, the disease has suboptimal treatment due to the rise of multidrug resistant strains of Mycobacterium tuberculosis (Mtb), the causative bacterial agent of tuberculosis. Therefore, we established a critical assay to identify novel drugs that interfere with specific Mtb virulence mechanisms. The mycobacterial protein fragment complementation (M-PFC) assay was developed to screen 725 compound drug panel to find candidate drugs that interfered with important virulence-causing protein interactions of Mtb. We targeted the EsxA EsxB and EsxMEsxN interactions of the type VII secretion systems of Mtb. Our screen identified 46 small molecules that inhibited both virulence interactions, exhibiting nonspecific activity against a model cell line in vitro as well as seven hits specific to one of the two cell lines. In the future, we hope to retest the seven unique positive hits to confirm their ability to inhibit specific proteinprotein interactions of Mtb.