Fig 9. Model whereby Mtb arrests the macrophage cell cycle to establish long term infection.

Mtb WhiB3 is a redox sensor that senses NO and low levels of oxygen (hypoxia) along with in vivo carbon sources available and accordingly modulates bioenergetic metabolism in response to the immediate environment. Bioenergetic homeostasis is essential for the transcription and production of polyketides under WhiB3 control. Lipids and polyketides are released from Mtb into the infected macrophage, where they arrest the host’s cell cycle and modulate the immune response to establish a persistent infection.