FtsZ-spirals and -arcs determine the shape of the invaginating septa in some mutants of Escherichia coli

Mol Microbiol. 1996 Oct;22(2):231-7. doi: 10.1046/j.1365-2958.1996.00100.x.


The essential cell division protein FtsZ forms a dynamic ring structure at the future division site. This Z-ring contracts during cell division while maintaining a position at the leading edge of the invaginating septum. Using immunofluorescence microscopy we have characterized two situations in which non-ring FtsZ structures are formed. In ftsZ26 (temperature sensitive, Ts) mutant cells, FtsZ-spirals are formed and lead to formation of spirally invaginating septa, which in turn cause morphological abnormalities. In rodAoul mutant cells, which grow as spheres instead of rods, FtsZ-arcs are formed where asymmetric septal invaginations are initiated. The FtsZ-arcs later mature into complete FtsZ-rings. Our data show that Z-spirals and Z-arcs can contract and that in doing so, they determine the shape of the invaginating septa. These results also strongly suggest that in normal cell division, FtsZ is positioned to a single nucleation site on the inner membrane, from which it polymerizes bidirectionally around the cell circumference to form the Z-ring.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Bacterial Proteins / analysis*
  • Bacterial Proteins / chemistry
  • Cell Division
  • Cytoskeletal Proteins*
  • Escherichia coli / chemistry
  • Escherichia coli / cytology*
  • Escherichia coli / genetics
  • GTP-Binding Proteins / analysis*
  • GTP-Binding Proteins / chemistry
  • Microscopy, Electron, Scanning
  • Microscopy, Fluorescence
  • Mutation
  • Phenotype
  • Temperature


  • Bacterial Proteins
  • Cytoskeletal Proteins
  • FtsZ protein, Bacteria
  • GTP-Binding Proteins