Mycolic acid (MA)

Mycolic acids are high-molecular-weight, alpha-branched, beta-hydroxy fatty acids that constitute a major and essential component of the cell wall of Mycobacterium species, including Mycobacterium tuberculosis (PubChem, 2024). They form a thick, waxy lipid layer known as the mycomembrane, which provides a formidable permeability barrier against many common antibiotics and host immune effector molecules (Marrakchi et al., 2014). This unique structure is vital for the survival of the bacteria within the harsh environment of the host macrophage and contributes significantly to the pathogen's virulence. Because mycolic acids are unique to the Mycolata taxon and indispensable for bacterial viability, their biosynthetic pathway is the focus of several key anti-tuberculosis therapies (Takayama et al., 2005). Drugs like isoniazid and ethionamide specifically target enzymes involved in the synthesis of these lipids, leading to the disruption of the cell wall and subsequent bacterial lysis (StatPearls, 2023).

Other names

Alpha-mycolic acidMethoxymycolic acidKetomycolic acidMycobacterial fatty acid

Inhibition of mycolic acid biosynthesis, primarily through the inhibition of the enoyl-ACP reductase (InhA) or other enzymes in the Fatty Acid Synthase II (FAS-II) system (StatPearls, 2023; Takayama et al., 2005).