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Updated: Jun 25, 2026
09:40
Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
Type VI secretion apparatus and phage tail-associated protein complexes share a common evolutionary origin.
Petr G Leiman1, Marek Basler, Udupi A Ramagopal
1Department of Biological Sciences, Purdue University, West Lafayette, IN 47906, USA.
Summary
Pathogenic microbes use protein secretion systems like the Type VI secretion system (T6SS). Researchers found T6SS components resemble bacteriophage tails, suggesting a similar protein and DNA translocation mechanism.
Area of Science:
- Microbiology
- Structural Biology
- Bacteriology
Background:
- Pathogenic microbes utilize diverse protein secretion systems for virulence.
- Gram-negative bacteria employ at least six distinct systems, including the Type VI secretion system (T6SS).
- The structural and functional mechanisms of T6SS components remain largely uncharacterized.
Purpose of the Study:
- To elucidate the structural and functional roles of key Type VI secretion system (T6SS) components.
- To investigate the homology between T6SS proteins and bacteriophage tail proteins.
Main Methods:
- Crystallographic analysis to determine protein structures.
- Biochemical assays to assess protein function.
- Bioinformatic analysis for homology detection.
Main Results:
- Identification of three T6SS components homologous to bacteriophage tail proteins.
- Characterization of a membrane-penetrating needle and associated proteins within the T6SS.
- Structural and functional resemblance between the T6SS extracellular apparatus and bacteriophage tails.
Conclusions:
- The Type VI secretion system (T6SS) functions as a complex machine analogous to bacteriophage tails.
- T6SS facilitates the translocation of proteins and potentially DNA across cell membranes.
- This finding provides insights into the molecular mechanisms of bacterial protein secretion and pathogenesis.
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