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Updated: Sep 5, 2025
10:41
Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance
Published on: January 3, 2012
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Delivery, structure, and function of bacterial genotoxins.
1Department of Microbiology and Immunology, Cornell University, Ithaca, NY, USA.
Virulence
|July 7, 2022
Summary
Bacterial genotoxins cause DNA breaks in host cells, potentially leading to cancer. This review examines how cytolethal distending toxin (CDT), typhoid toxin, and colibactin reach the cell nucleus to perform their genotoxic functions.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Bacterial genotoxins are virulence factors causing DNA damage in host cells.
- Unresolved DNA damage can lead to apoptosis, senescence, and cancer.
- Key genotoxins include cytolethal distending toxin (CDT), typhoid toxin, and colibactin.
Purpose of the Study:
- To review the mechanisms of nuclear delivery for bacterial genotoxins.
- To discuss the structural and functional genotoxic actions of these toxins.
Main Methods:
- Literature review focusing on genotoxin mechanisms.
- Analysis of nuclear translocation pathways.
- Examination of DNA damage induction processes.
Main Results:
- CDT, typhoid toxin, and colibactin employ distinct strategies for nuclear entry.
- These toxins induce DNA breaks (SSBs and DSBs) and interstrand cross-links.
- Genotoxicity contributes to host cell dysfunction and potential oncogenesis.
Conclusions:
- Understanding genotoxin mechanisms is crucial for combating bacterial pathogenesis and related diseases.
- Targeting nuclear delivery or DNA repair inhibition could be therapeutic strategies.
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