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Updated: Oct 21, 2025
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From Constructs to Crystals – Towards Structure Determination of β-barrel Outer Membrane Proteins
Published on: July 4, 2016
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Structural characterization of hexameric shell proteins from two types of choline-utilization bacterial
Jessica M Ochoa1, Oscar Mijares2, Andrea A Acosta2
1UCLA Molecular Biology Institute, University of California Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA.
Acta Crystallographica. Section F, Structural Biology Communications
|September 2, 2021
Summary
Bacterial microcompartments optimize metabolism using protein shells. Researchers characterized six shell protein structures from choline-utilizing microcompartments, revealing shared electrostatic properties.
Area of Science:
- Biochemistry
- Structural Biology
- Microbiology
Background:
- Bacterial microcompartments (BMCs) are protein shells optimizing metabolic pathways.
- Their shells, formed by thousands of hexameric protein subunits, enclose enzymes.
- The structure of BMCs involved in choline metabolism using glycyl radical enzymes remains poorly understood.
Purpose of the Study:
- To characterize the protein shell structures of type I and type II choline-utilization BMCs.
- To identify conserved features among shell proteins involved in choline metabolism.
Main Methods:
- X-ray crystallography was used to determine the structures of six hexameric shell proteins.
- Bioinformatic analyses, including sequence and electrostatic surface property comparisons, were performed.
Main Results:
- Six distinct hexameric shell protein structures from choline-utilizing BMCs were resolved.
- Analysis revealed conserved electrostatic surface properties across different types of shell proteins.
- These findings provide insights into the assembly and function of these BMCs.
Conclusions:
- The structural and electrostatic data advance our understanding of choline-metabolizing BMCs.
- Conserved features suggest common principles in BMC shell formation and function.
- Further research can leverage these structures to investigate BMC-mediated metabolic processes.
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