Tuberculosis is a serious infectious disease and one of the leading causes of death worldwide. The disease-causing bacteria, called Mycobacterium tuberculosis, are depicted in the drawing in red. To overcome stress conditions, these bacteria can slow down their growth using special pairs of genes that encode both a toxic protein and an antitoxin that functions as an antidote.

This drawing illustrates the discovery of a particularly exciting toxin (the Pac-Man) that can actually kill the bacteria in the absence of its antitoxin (shown in cyan). The toxin ‘eats up’ NAD+, which are important molecules that enable fundamental chemical reactions, causing the bacteria to die. In the bacterium in the back, the Pac-Man’s mouth is blocked by the antitoxin, preventing the degradation of NAD+and allowing normal growth.

Check out the exciting Molecular Cell paper by Annabel Parret from the Wilmanns group at EMBL Hamburg, the Neyrolles lab at IPBS, CNRS-Université de Toulouse, and the Carvalho group at the Francis Crick Institute.

A Pac-Man Toxin in Tuberculosis
A newly discovered toxin triggers cell death by ‘eating up’ the NAD+ within the bacterium.