[Biosynthesis and regulation of mycolic acids in Mycobacterium tuberculosis--a review]

Tuberculosis (TB) is one of the world's deadliest diseases. Approximately eight million individuals develop active tuberculosis annually, and two million die of tuberculosis. The emergence of multi-drug resistance strains, HIV co-infection, and an increasing aging population further worsen this scenario. Mycolic acids (MAs, also mycolate) are integral cell wall components of Mycobacterium tuberculosis, other mycobacterium and most actinomycetes, engaging in the remarkable survival ability of Mycobacterium tuberculosis within infected hosts, virulence and evasion of immunity. The biosynthesis and regulation of mycolic acids are rife with anti-tuberculosis drug targets. First-line tuberculosis drugs such as isoniazid and ethambutol target this pathway. In-depth investigation of this aspect will provide more opportunities to find better measures to combat tuberculosis. To this end, we reviewed the structures, classification, biosynthesis pathway, regulation factors in pathway of mycolic acid, as well as promising drug targets.