Cell wall synthesizing complexes in Mycobacteriales

Curr Opin Microbiol. 2024 Jun:79:102478. doi: 10.1016/j.mib.2024.102478. Epub 2024 Apr 22.


Members of the order Mycobacteriales are distinguished by a characteristic diderm cell envelope, setting them apart from other Actinobacteria species. In addition to the conventional peptidoglycan cell wall, these organisms feature an extra polysaccharide polymer composed of arabinose and galactose, termed arabinogalactan. The nonreducing ends of arabinose are covalently linked to mycolic acids (MAs), forming the immobile inner leaflet of the highly hydrophobic MA membrane. The contiguous outer leaflet of the MA membrane comprises trehalose mycolates and various lipid species. Similar to all actinobacteria, Mycobacteriales exhibit apical growth, facilitated by a polar localized elongasome complex. A septal cell envelope synthesis machinery, the divisome, builds instead of the cell wall structures during cytokinesis. In recent years, a growing body of knowledge has emerged regarding the cell wall synthesizing complexes of Mycobacteriales., focusing particularly on three model species: Corynebacterium glutamicum, Mycobacterium smegmatis, and Mycobacterium tuberculosis.

Publication types

  • Review

MeSH terms

  • Arabinose / metabolism
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Cell Wall* / metabolism
  • Corynebacterium glutamicum / genetics
  • Corynebacterium glutamicum / growth & development
  • Corynebacterium glutamicum / metabolism
  • Galactans* / metabolism
  • Mycobacterium smegmatis / genetics
  • Mycobacterium smegmatis / growth & development
  • Mycobacterium smegmatis / metabolism
  • Mycobacterium tuberculosis / genetics
  • Mycobacterium tuberculosis / metabolism
  • Mycolic Acids* / metabolism
  • Peptidoglycan / metabolism


  • Mycolic Acids
  • Galactans
  • arabinogalactan
  • Peptidoglycan
  • Arabinose
  • Bacterial Proteins