Informing Drug Synergy: Investigating Mycobacterial Membrane Protein Structure and Function

Abstract The multi-layered cell envelope of Mycobacterium tuberculosis (Mtb) is a critical barrier to antibiotics and an important target for drug development. Disrupting its assembly increases bacterial susceptibility to existing antibiotics, creating opportunities for synergistic therapies. This proposal aims to elucidate the molecular mechanisms underlying envelope assembly, focusing on key membrane proteins, whose structures we have determined. Aim 1 investigates the cytoplasmic synthesis and transport of mycolic acids, essential fatty acids in the mycomembrane, by investigating the spatio-temporal localization of Pks13 and its interaction with fatty acid synthases. Aim 2 defines the physiological role of the essential efflux pump EfpA, hypothesizing it functions as a lipid transporter, and explores its inhibition as a therapeutic strategy. Aim 3 characterizes proteins that coordinate mycomembrane biosynthesis, particularly PgfA, to understand how this process is regulated for balanced cell growth. These studies will provide crucial insights into M. tuberculosis envelope construction, paving the way for novel, synergistic TB therapies that enhance the efficacy of existing treatments.