The Plasticity of Molecular Interactions Governs Bacterial Microcompartment Shell Assembly

Basil J Greber; Markus Sutter; Cheryl A Kerfeld

doi:10.1016/j.str.2019.01.017

The Plasticity of Molecular Interactions Governs Bacterial Microcompartment Shell Assembly

Structure. 2019 May 7;27(5):749-763.e4. doi: 10.1016/j.str.2019.01.017. Epub 2019 Mar 1.

Authors

Basil J Greber¹, Markus Sutter², Cheryl A Kerfeld³

Affiliations

¹ California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA 94720, USA; Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
² Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; MSU-DOE Plant Research Laboratory and Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA.
³ Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; MSU-DOE Plant Research Laboratory and Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. Electronic address: ckerfeld@lbl.gov.

Abstract

Bacterial microcompartments (BMCs) are composed of an enzymatic core encapsulated by a selectively permeable protein shell that enhances catalytic efficiency. Many pathogenic bacteria derive competitive advantages from their BMC-based catabolism, implicating BMCs as drug targets. BMC shells are of interest for bioengineering due to their diverse and selective permeability properties and because they self-assemble. A complete understanding of shell composition and organization is a prerequisite for biotechnological applications. Here, we report the cryoelectron microscopy structure of a BMC shell at 3.0-Å resolution, using an image-processing strategy that allowed us to determine the previously uncharacterized structural details of the interactions formed by the BMC-T^S and BMC-T^D shell subunits in the context of the assembled shell. We found unexpected structural plasticity among these interactions, resulting in distinct shell populations assembled from varying numbers of the BMC-T^S and BMC-T^D subunits. We discuss the implications of these findings on shell assembly and function.

Keywords: bacterial microcompartments; bioengineering; cryoelectron microscopy; metabolosome; microbiology; modular assembly; permeability; structural biology.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Algorithms
Bacterial Proteins / chemistry*
Cryoelectron Microscopy
Ligands
Metabolome
Myxococcales / chemistry*
Organelles / chemistry
Permeability
Protein Multimerization
Protein Structure, Secondary
Software

Substances

Bacterial Proteins
Ligands

Supplementary concepts

Haliangium ochraceum

Grants and funding

R01 AI114975/AI/NIAID NIH HHS/United States