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Updated: Aug 5, 2025
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High-Resolution Comparison of Bacterial Conjugation Frequencies
Published on: January 10, 2019
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Diverse and abundant phages exploit conjugative plasmids
Natalia Quinones-Olvera1,2,3, Siân V Owen1,2,3, Lucy M McCully1,2,3
1Department of Biomedical Informatics, Harvard Medical School, Boston, MA 02115, USA.
Biorxiv : the Preprint Server for Biology
|March 30, 2023
Summary
New plasmid-dependent phages targeting IncP and IncF plasmids are common in wastewater. These phages, mostly non-canonical types, are crucial for understanding bacterial evolution and horizontal gene transfer.
Area of Science:
- Microbiology
- Evolutionary Biology
- Virology
Background:
- Bacteriophages (phages) are critical drivers of bacterial evolution, typically using cell surface structures as receptors.
- Plasmid-dependent phages uniquely utilize plasmid-encoded proteins for infection, making their host range contingent on plasmid mobility.
- Characterization of plasmid-dependent phages is limited despite their biotechnological potential.
Approach:
- Systematic search for novel plasmid-dependent phages targeting IncP and IncF plasmids using a dedicated discovery platform.
- Isolation and characterization of 64 phages from wastewater samples.
- Analysis of phage diversity, host range, genetic makeup, and evolutionary implications.
Key Points:
- Plasmid-dependent phages are abundant and genetically diverse in wastewater, with most being non-canonical types (tectiviruses, ssDNA filamentous, ssRNA phages).
- Plasmid-dependent tectiviruses display varied host ranges linked to holin protein variations.
- Culture-based discovery remains vital as these phages are often missed in metaviromic analyses.
Conclusions:
- Plasmid-dependent phages, particularly tectiviruses, are prevalent and understudied, impacting bacterial evolution.
- The discovery of a tailed IncF plasmid-dependent phage and related genes highlights the adaptable use of type 4 pilus structures by phages.
- These phages play a significant, under-appreciated role in regulating horizontal gene transfer mediated by conjugative plasmids.
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