The cause of tuberculosis is Mycobacterium tuberculosis (Mtb), a slow-growing aerobic bacterium that divides every 16 to 20 hours. Scientists know that carbon metabolism plays a significant role in the ability of Mtb to replicate and persist in the body and that fatty acids are the major source of carbon and energy during infection. However, the specific enzymes required for the metabolism of fatty acids have not been completely defined. New research sheds light on a previously unrecognized aspect of fatty acid metabolism that could potentially lead to new targets for drug therapy.