Given the enormous health burden of Tuberculosis, great effort has been invested into understanding the molecular mechanisms governing mycobacterial pathogenesis. The ability of Mycobacterium tuberculosis to sense and adapt to changes in its environment is key to its long-term survival within its host cell. Two-component systems (2CRs) represent important genetic regulatory elements that enable efficient responses to these environments. We sought to characterise a novel mycobacterial 2CR, LirAB, and understand its control of key virulence and persistence-associated genes within its regulon. Transcriptional analysis demonstrates LirAB responds to several intra-macrophage environments, including changes in pH and iron, and regulates the expression of genes involved in fatty acid metabolism, cell-wall stress and lipid detoxification. Further characterisation of one such LirAB-controlled gene, referred to here as ppvp, is associated with host adhesion and enhanced cell death during infection of murine macrophages. Molecular tracking of PPVP-coated beads indicates this protein localises to the nuclear membrane following internalisation. Our work suggests a multi-functional role for the LirAB 2CR and highlights the importance of environmental sensing on the regulation of M. tuberculosis infection pathways.