PomX, a ParA/MinD ATPase activating protein, is a triple regulator of cell division in Myxococcus xanthus
Cell division site positioning is precisely regulated but the underlying mechanisms are incompletely understood. In the social bacterium Myxococcus xanthus, the ~15 MDa tripartite PomX/Y/Z complex associates with and translocates across the nucleoid in a PomZ ATPase-dependent manner to directly position and stimulate formation of the cytokinetic FtsZ-ring at midcell, and then undergoes fission during division. Here, we demonstrate that PomX consists of two functionally distinct domains and has three functions. The N-terminal domain stimulates ATPase activity of the ParA/MinD ATPase PomZ. The C-terminal domain interacts with PomY and forms polymers, which serve as a scaffold for PomX/Y/Z complex formation. Moreover, the PomX/PomZ interaction is important for fission of the PomX/Y/Z complex. These observations together with previous work support that the architecturally diverse ATPase activating proteins of ParA/MinD ATPases are highly modular and use the same mechanism to activate their cognate ATPase via a short positively charged N-terminal extension.
All data supporting this study are available within the article and supporting files. Source data files have been provided for Figures 1, 2, 3, 4, 5 and 6.
Article and author information
Deutsche Forschungsgemeinschaft (TRR 174)
- Erwin Frey
- Lotte Sogaard-Andersen
Max Planck Gesellschaft (NA)
- Lotte Sogaard-Andersen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Gisela Storz, National Institute of Child Health and Human Development, United States
- Received: December 30, 2020
- Accepted: March 17, 2021
- Accepted Manuscript published: March 18, 2021 (version 1)
- Version of Record published: March 24, 2021 (version 2)
© 2021, Schumacher et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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