Timing of Z-ring localization in Escherichia coli

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • R Tsukanov - , Ben-Gurion University of the Negev (Author)
  • G Reshes - (Author)
  • G Carmon - (Author)
  • E Fischer-Friedrich - , Weizmann Institute of Science (Author)
  • N S Gov - (Author)
  • I Fishov - (Author)
  • M Feingold - (Author)

Abstract

Bacterial cell division takes place in three phases: Z-ring formation at midcell, followed by divisome assembly and building of the septum per se. Using time-lapse microscopy of live bacteria and a high-precision cell edge detection method, we have previously found the true time for the onset of septation, τ(c), and the time between consecutive divisions, τ(g). Here, we combine the above method with measuring the dynamics of the FtsZ-GFP distribution in individual Escherichia coli cells to determine the Z-ring positioning time, τ(z). To analyze the FtsZ-GFP distribution along the cell, we used the integral fluorescence profile (IFP), which was obtained by integrating the fluorescence intensity across the cell width. We showed that the IFP may be approximated by an exponential peak and followed the peak evolution throughout the cell cycle, to find a quantitative criterion for the positioning of the Z-ring and hence the value of τ(z). We defined τ(z) as the transition from oscillatory to stable behavior of the mean IFP position. This criterion was corroborated by comparison of the experimental results to a theoretical model for the FtsZ dynamics, driven by Min oscillations. We found that τ(z) < τ(c) for all the cells that were analyzed. Moreover, our data suggested that τ(z) is independent of τ(c), τ(g) and the cell length at birth, L(0). These results are consistent with the current understanding of the Z-ring positioning and cell septation processes.

Details

Original languageEnglish
Pages (from-to)066003
JournalPhysical biology
Volume8
Issue number6
Publication statusPublished - Dec 2011
Peer-reviewedYes
Externally publishedYes

External IDs

Scopus 82955188134
ORCID /0000-0002-2433-916X/work/142250438

Keywords

Keywords

  • Bacterial Proteins/analysis, Cell Cycle, Cytoskeletal Proteins/analysis, Escherichia coli/cytology, Green Fluorescent Proteins/analysis, Microscopy, Fluorescence/methods