The role of corynomycolic acids in Corynebacterium-host interaction

Within the Actinobacteria, the genera Corynebacterium, Mycobacterium, Nocardia and Rhodococcus form the so-called CMNR group, also designated as mycolic acid-containing actinomycetes. Almost all members of this group are characterized by a mycolic acid layer, the mycomembrane, which covers the cell wall and is responsible for a high resistance of these bacteria against chemical and antibiotic stress. Furthermore, components of the mycomembrane are crucial for the interaction of bacteria with host cells. This review summarizes the current knowledge of mycolic acid synthesis and interaction with components of the immune system for the genus Corynebacterium with an emphasis on the pathogenic species Corynebacterium diphtheriae, Corynebacterium pseudotuberculosis and Corynebacterium ulcerans as well as the biotechnology workhorse Corynebacterium glutamicum.