1. Physics of Living Systems
  2. Computational and Systems Biology
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Many-molecule encapsulation by an icosahedral shell

  1. Jason D Perlmutter
  2. Farzaneh Mohajerani
  3. Michael F Hagan  Is a corresponding author
  1. Brandeis University, United States
Research Article
  • Cited 20
  • Views 2,554
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Cite this article as: eLife 2016;5:e14078 doi: 10.7554/eLife.14078


We computationally study how an icosahedral shell assembles around hundreds of molecules. Such a process occurs during the formation of the carboxysome, a bacterial microcompartment that assembles around many copies of the enzymes ribulose 1,5-bisphosphate carboxylase/oxygenase and carbonic anhydrase to facilitate carbon fixation in cyanobacteria. Our simulations identify two classes of assembly pathways leading to encapsulation of many-molecule cargoes. In one, shell assembly proceeds concomitantly with cargo condensation. In the other, the cargo first forms a dense globule; then, shell proteins assemble around and bud from the condensed cargo complex. Although the model is simplified, the simulations predict intermediates and closure mechanisms not accessible in experiments, and show how assembly can be tuned between these two pathways by modulating protein interactions. In addition to elucidating assembly pathways and critical control parameters for microcompartment assembly, our results may guide the reengineering of viruses as nanoreactors that self-assemble around their reactants.

Article and author information

Author details

  1. Jason D Perlmutter

    Martin Fisher School of Physics, Brandeis University, Waltham, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Farzaneh Mohajerani

    Martin Fisher School of Physics, Brandeis University, Waltham, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Michael F Hagan

    Martin Fisher School of Physics, Brandeis University, Waltham, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Nir Ben-Tal, Tel Aviv University, Israel

Publication history

  1. Received: December 27, 2015
  2. Accepted: May 10, 2016
  3. Accepted Manuscript published: May 11, 2016 (version 1)
  4. Version of Record published: June 28, 2016 (version 2)
  5. Version of Record updated: July 12, 2016 (version 3)


© 2016, Perlmutter 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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Further reading

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