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Updated: Jun 15, 2025

Author Spotlight: Investigating Bacteriophage-Induced Immune Responses in Gnotobiotic Mice
Published on: January 26, 2024
The role of TIR domain-containing proteins in bacterial defense against phages
Shuangshuang Wang1,2,3, Sirong Kuang1,2,3, Haiguang Song1,2,3
1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
Abstract:
Toll/interleukin-1 receptor (TIR) domain-containing proteins play a critical role in immune responses in diverse organisms, but their function in bacterial systems remains to be fully elucidated. This study, focusing on Escherichia coli, addresses how TIR domain-containing proteins contribute to bacterial immunity against phage attack. Through an exhaustive survey of all E. coli genomes available in the NCBI database and testing of 32 representatives of the 90% of the identified TIR domain-containing proteins, we found that a significant proportion (37.5%) exhibit antiphage activities. These defense systems recognize a variety of phage components, thus providing a sophisticated mechanism for pathogen detection and defense. This study not only highlights the robustness of TIR systems in bacterial immunity, but also draws an intriguing parallel to the diversity seen in mammalian Toll-like receptors (TLRs), enriching our understanding of innate immune mechanisms across life forms and underscoring the evolutionary significance of these defense strategies in prokaryotes.
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