Mycobacterium tuberculosis cell wall biosynthesis pathway (Mtb cell wall biosynthesis)

The Mycobacterium tuberculosis cell wall biosynthesis pathway is a complex metabolic network responsible for constructing the unique, lipid-rich envelope of the bacterium, which is essential for its survival, virulence, and resistance to environmental stress (Dulberger et al., 2020). This envelope is characterized by the mycolic acid-arabinogalactan-peptidoglycan (mAGP) complex, a structure that provides a formidable physical barrier against host immune defenses and many standard antibiotics (Abrahams & Besra, 2018). Key enzymes within this pathway, such as the enoyl-ACP reductase (InhA) and various arabinosyltransferases (EmbCAB), serve as the primary targets for frontline anti-tuberculosis drugs like isoniazid and ethambutol (Marrakchi et al., 2014). Inhibition of these enzymes leads to the disruption of cell wall integrity, resulting in bacterial lysis and death. Because many components of this pathway are unique to the Mycobacterium genus and lack human homologs, it remains one of the most productive areas for the development of highly selective anti-infective agents (PubChem). However, the emergence of multi-drug resistant strains continues to drive research into novel targets within this pathway, such as DprE1 and Pks13, to overcome existing resistance mechanisms. The pathway also involves the synthesis of lipoarabinomannan (LAM), which plays a crucial role in modulating the host immune response during infection. Therapeutic challenges include the slow growth of the pathogen and its ability to enter a dormant state where cell wall synthesis is downregulated, complicating treatment efficacy.

Other names

mAGP biosynthesisMycobacterial cell envelope synthesisMtb cell wall synthesisMycolic acid-arabinogalactan-peptidoglycan biosynthesis

Inhibition of mycolic acid synthesis, arabinogalactan synthesis, and peptidoglycan assembly through the targeting of specific enzymes such as InhA, EmbB, and DprE1.