The bacterial cytoskeleton: in vivo dynamics of the actin-like protein Mbl of Bacillus subtilis

Dev Cell. 2003 Jan;4(1):19-28. doi: 10.1016/s1534-5807(02)00403-3.


Mbl is a bacterial actin homolog that controls cell morphogenesis in Bacillus subtilis. A functional GFP-Mbl fusion protein was used to examine the behavior of the helical cables formed by Mbl protein in live B. subtilis cells. The cables undergo dynamic changes during cell cycle progression. They are stable but not rigid while elongating in parallel with cell growth, and they require septum formation to divide/cleave. Fluorescence recovery after photobleaching (FRAP) analysis showed that the cables are continuously remodeled during cell elongation. Turnover occurs along the length of the helical Mbl filaments, with no obvious polarity and a recovery half-time of about 8 min. These findings have important implications for the nature of bacterial cell wall architecture and synthesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism
  • Bacillus subtilis / cytology*
  • Bacillus subtilis / metabolism*
  • Bacterial Proteins / metabolism*
  • Cell Division
  • Cell Polarity
  • Cell Wall / metabolism
  • Cytoskeletal Proteins / metabolism*
  • Cytoskeleton / metabolism*
  • Fluorescence Recovery After Photobleaching
  • Macromolecular Substances
  • Microscopy, Fluorescence


  • Actins
  • Bacterial Proteins
  • Cytoskeletal Proteins
  • Macromolecular Substances
  • mbl protein, Bacillus subtilis