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Cited by 4Bacterial Genetics and BiotechnologyAdvanced Electron Microscopy Techniques and ApplicationsAntibiotic Resistance in Bacteria

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Structure of the conjugation surface exclusion protein TraT

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Chen, Nicolas, Bukys, Alfredas, Lundgren, Camilla A. K., Deme, Justin C., El Sayyed, Hafez, Kapanidis, Achillefs N., Lea, Susan M., Berks, Ben C.·2025·Communications Biology
DOI 10.1038/s42003-025-09102-8PMC PMC12258729

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Abstract

Conjugal transfer of plasmids between bacteria is a major route for the spread of antimicrobial resistance. Many conjugative plasmids encode exclusion systems that inhibit redundant conjugation. In incompatibility group F (IncF) plasmids surface exclusion is mediated by the outer membrane protein TraT. Here we report the cryoEM structure of the TraT exclusion protein complex from the canonical F plasmid of Escherichia coli . TraT is a hollow homodecamer shaped like a chef’s hat. In contrast to most outer membrane proteins, TraT spans the outer membrane using transmembrane α-helices. We develop a microscopy-based conjugation assay to probe the effects of directed mutagenesis on TraT. Our analysis provides no support for the idea that TraT has specific interactions with partner proteins. Instead, we infer that TraT is most likely to function by physical interference with conjugation. This work provides structural insight into a natural inhibitor of microbial gene transfer.

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Metadata

Authors
Chen, N., Bukys, A., Lundgren, C. A. K., Deme, J. C., El Sayyed, H., Kapanidis, A. N., Lea, S. M., & Berks, B. C.
Affiliations
  • University of Oxford (GB)
  • National Cancer Institute (US)
  • St. Jude Children's Research Hospital (US)
Corresponding author
  • Lea, Susan M.
  • Berks, Ben C.
ORCID
Venue
Communications Biology
Publisher
Springer Science and Business Media LLC
Published
2025-11-26
Volume
8
Issue
1
Pages
1702-1702
ISSN
2399-3642 (ISSN-L)
DOI
10.1038/s42003-025-09102-8
PMC
PMC12258729
OpenAlex
W4416718874
Cited by
4
References
1
Citations by year
2026: 4
FWCI
2.35
Type
journal article
Language
en
Open access
Licence
Locations
  • Communications Biology (publishedVersion, cc-by)
  • bioRxiv (Cold Spring Harbor Laboratory) (acceptedVersion, cc-by)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (submittedVersion, cc-by)
  • PubMed Central (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • Wellcome Trust (226662/Z/22/Z)
  • Merton College, University of Oxford
  • University of Oxford
  • Directorate for Biological Sciences
  • Biotechnology and Biological Sciences Research Council (BB/S007474/1)
  • Clarendon Fund
  • H2020 European Research Council (833713)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Bacterial Genetics and Biotechnology
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Structural Biology › Advanced Electron Microscopy Techniques and Applications
  • Health Sciences › Medicine › Microbiology (medical) › Antibiotic Resistance in Bacteria
Keywords
traT, IncF plasmids, F plasmid, Escherichia coli, outer membrane proteins, transmembrane helices, conjugation inhibition, plasmid conjugation, antimicrobial resistance dissemination, cryo-EM structure

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