A Unified Model for Treadmilling and Nucleation of Single-Stranded FtsZ Protofilaments.

Thumbnail Image



Journal Title

Journal ISSN

Volume Title

Repository Usage Stats


Citation Stats


Bacterial cell division is tightly coupled to the dynamic behavior of FtsZ, a tubulin homolog. Recent experimental work in vitro and in vivo has attributed FtsZ's assembly dynamics to treadmilling, in which subunits add to the bottom and dissociate from the top of protofilaments. However, the molecular mechanisms producing treadmilling have yet to be characterized and quantified. We have developed a Monte Carlo model for FtsZ assembly that explains treadmilling, and also explains assembly nucleation by the same mechanisms. A key element of the model is a conformational change from R (relaxed), which is highly favored for monomers, to T (tense), which is favored for subunits in a protofilament. This model was created in MATLAB. Kinetic parameters were converted to probabilities of execution during a single, small time step. These were used to stochastically determine FtsZ dynamics. Our model is able to accurately describe the results of several in vitro and in vivo studies for a variety of FtsZ flavors. With standard conditions, the model FtsZ polymerized and produced protofilaments that treadmilled at 23 nm/s, hydrolyzed GTP at 3.6-3.7 GTP min-1 FtsZ-1, and had an average length of 30-40 subunits, all similar to experimental results. Adding a bottom capper resulted in shorter protofilaments and higher GTPase, similar to the effect of the known bottom capper protein MciZ. The model could match nucleation kinetics of several flavors of FtsZ using the same parameters as treadmilling and varying only the R to T transition of monomers.






Published Version (Please cite this version)


Publication Info

Corbin, Lauren C, and Harold P Erickson (2020). A Unified Model for Treadmilling and Nucleation of Single-Stranded FtsZ Protofilaments. Biophysical journal, 119(4). pp. 792–805. 10.1016/j.bpj.2020.05.041 Retrieved from https://hdl.handle.net/10161/22297.

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.



Harold Paul Erickson

James B. Duke Distinguished Professor Emeritus

Recent research has been on cytoskeleton (eukaryotes and bacteria); a skirmish to debunk the irisin story; a reinterpretation of proposed multivalent binders of the coronavirus spike protein. I have also published an ebook on "Principles of Protein-Protein Association" suitable for a course module or individual learning.

Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.