Activation of the MprBA two-component system in Mycobacterium smegmatis under acidic and respiration-inhibitory conditions and crosstalk between MprA and KdpD.

Activation of the MprBA two-component system in Mycobacterium smegmatis occurs under acidic and respiration-inhibitory conditions, with KdpD kinase compensating for MprB absence.

• Why it matters: Understanding how mycobacteria respond to environmental stresses is crucial for developing strategies against persistent infections, as these pathways influence survival and drug resistance.
• What they did: The study used genetic inactivation, chemical inhibition, and CRISPRi techniques to analyze MprBA activation, revealing that MprA can be phosphorylated by KdpD when MprB is absent, and that the N-terminal domain of MprB is essential for environmental sensing.
• The result: Findings demonstrate that the MprBA pathway is vital for growth under acidic stress, and that crosstalk between KdpD and MprA enhances stress response flexibility, offering potential targets for therapeutic intervention.