Mycobacterium tuberculosis capsule

The **Mycobacterium tuberculosis capsule** is the outermost structure of the bacterium and plays a critical role in protecting the bacillus from host immune responses[1][5]. Its main component is a glycogen-like α-glucan, with lower amounts of arabinomannan, mannan, proteins, and lipids[1]. The capsule facilitates pathogen survival and virulence by mediating interactions with phagocytes and contributing to immune evasion[3][1]. Targeting the capsule or its biosynthetic pathways is an emerging anti-infective strategy, but clinical drugs currently target deeper layers of the cell envelope (e.g., mycolic acids, arabinogalactan, peptidoglycan) rather than the capsule itself[4][2]. Vaccination and novel drug approaches are being explored to target capsule components directly[1]. If a more precise molecular target is required (such as a capsule biosynthesis enzyme or a specific cell wall synthesis enzyme), that information would need to be specified, as "capsule formation" encompasses multiple molecular pathways and components.

Other names

M. tuberculosis capsuleTubercle bacillus capsuleMtb capsuleMycobacterial capsule

Inhibition of capsule or cell wall biosynthetic enzymes disrupts assembly of the protective envelope, compromising bacterial survival and increasing susceptibility to host defenses and antibiotics[1][4][2].