A new view into prokaryotic cell biology from electron cryotomography

Electron cryotomography (ECT) enables intact cells to be visualized in 3D in an essentially native state to 'macromolecular' ( ∼ 4 nm) resolution, revealing the basic architectures of complete nanomachines and their arrangements in situ. Since its inception, ECT has advanced our understanding of many aspects of prokaryotic cell biology, from morphogenesis to subcellular compartmentalization and from metabolism to complex interspecies interactions. In this Review, we highlight how ECT has provided structural and mechanistic insights into the physiology of bacteria and archaea and discuss prospects for the future.

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Acknowledgements

The authors apologize that they could not discuss all of the work in this burgeoning field. The authors thank members of the Jensen laboratory for helpful comments on the manuscript, and J. Ding and Y.-W. Chang for producing the accompanying movie. The authors also thank L. Sockett (University of Nottingham) for the gift of the Bdellovibrio bacteriovorus strain imaged in figure 1 and shown in the accompanying movie. Microbial electron cryotomography (ECT) in the Jensen laboatory is supported, in part, by the Howard Hughes Medical Institute, the US National Institutes of Health (grants RO1 GM101425 and RO1 GM094800), the Beckman Institute at Caltech, Caltech's Center for Environmental Microbial Interactions, and gifts to Caltech from the Gordon and Betty Moore Foundation and the Agouron Institute.

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Authors and Affiliations

  1. Howard Hughes Medical Institute; Division of Biology and Biological Engineering, California Institute of Technology, Catherine M. Oikonomou, Yi-Wei Chang & Grant J. Jensen
  2. Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, 91125, California, USA Catherine M. Oikonomou, Yi-Wei Chang & Grant J. Jensen
  1. Catherine M. Oikonomou