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Bacterial morphogenesis and the enigmatic MreB helix

Nature Reviews Microbiology volume 13, pages 241–248 (2015)Cite this article

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Abstract

Work over the past decade has highlighted the pivotal role of the actin-like MreB family of proteins in the determination and maintenance of rod cell shape in bacteria. Early images of MreB localization revealed long helical filaments, which were suggestive of a direct role in governing cell wall architecture. However, several more recent, higher-resolution studies have questioned the existence or importance of the helical structures. In this Opinion article, I navigate a path through these conflicting reports, revive the helix model and summarize the key questions that remain to be answered.

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Figure 1: The helical filament and dynamic patch models for MreB localization.
Figure 2: General interrelationships among cell shape, MreB filaments and the cell wall synthesis machinery.
Figure 3: Revised model for the role of MreB in shape determination.

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Acknowledgements

Work on cell wall synthesis in the Errington laboratory is supported by grant BB/G015902/1 from the UK Biotechnology and Biological Sciences Research Council. The author thanks W. Vollmer, L. J. Wu and K. Gerdes for helpful discussions and comments on the manuscript.

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  1. Jeff Errington is at the Centre for Bacterial Cell Biology, Medical Faculty, Newcastle University, Richardson Road, Newcastle-upon-Tyne NE2 4AX, UK.,

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Correspondence to Jeff Errington.

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Errington, J. Bacterial morphogenesis and the enigmatic MreB helix. Nat Rev Microbiol 13, 241–248 (2015). https://doi.org/10.1038/nrmicro3398

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