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Updated: Jul 20, 2026
06:10
Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
Summary
Researchers characterized unstable coliphage 18 using gentle techniques. Electron microscopy revealed its structure, while DNA analysis distinguished it from related phages, detailing its genome size and composition.
Area of Science:
- Bacteriology
- Molecular Biology
- Virology
Background:
- Coliphage 18 is a noninducible bacteriophage that is morphologically similar to P2 but exhibits heteroimmunity.
- Its instability presents challenges for detailed study and characterization.
Purpose of the Study:
- To characterize the morphology and genetic material of coliphage 18.
- To differentiate coliphage 18 from related phages like P2, 299, and 186.
Main Methods:
- Gentle lysis and mounting techniques for electron microscopy.
- Restriction endonuclease digestion of phage 18 DNA using BamHI.
- DNA melting point and buoyant density measurements.
Main Results:
- Electron microscopy revealed a contractile tail (130 nm) and isometric head (50 nm capsid diameter).
- BamHI digestion produced a unique restriction pattern distinct from P2, 299, and 186 phages.
- Genome size was determined to be 33.5 kb, with a G+C content of 55.0% and a buoyant density of 1.715 g/cm³.
Conclusions:
- Coliphage 18 possesses distinct morphological and genomic features differentiating it from related phages.
- Established gentle isolation and characterization methods facilitate the study of unstable phages.
- Detailed genomic and physical properties of coliphage 18 were elucidated.
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