Hyphal compartmentalization and sporulation in Streptomyces require the conserved cell division protein SepX

Nat Commun. 2022 Jan 10;13(1):71. doi: 10.1038/s41467-021-27638-1.


Filamentous actinobacteria such as Streptomyces undergo two distinct modes of cell division, leading to partitioning of growing hyphae into multicellular compartments via cross-walls, and to septation and release of unicellular spores. Specific determinants for cross-wall formation and the importance of hyphal compartmentalization for Streptomyces development are largely unknown. Here we show that SepX, an actinobacterial-specific protein, is crucial for both cell division modes in Streptomyces venezuelae. Importantly, we find that sepX-deficient mutants grow without cross-walls and that this substantially impairs the fitness of colonies and the coordinated progression through the developmental life cycle. Protein interaction studies and live-cell imaging suggest that SepX contributes to the stabilization of the divisome, a mechanism that also requires the dynamin-like protein DynB. Thus, our work identifies an important determinant for cell division in Streptomyces that is required for cellular development and sporulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Biological Phenomena
  • Cell Division / physiology*
  • Cell Wall
  • Hyphae / cytology
  • Hyphae / genetics
  • Hyphae / growth & development
  • Hyphae / metabolism*
  • Life Cycle Stages
  • Spores, Bacterial / genetics
  • Spores, Bacterial / metabolism*
  • Streptomyces / cytology
  • Streptomyces / genetics
  • Streptomyces / growth & development
  • Streptomyces / metabolism*


  • Bacterial Proteins

Supplementary concepts

  • Streptomyces venezuelae