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DETACHMENT OF BACTERIOPHAGE FROM ITS CARRIER PARTICLES
1Department of Bacteriology and Immunology, Washington University Medical School, St. Louis.
The Journal of General Physiology
|October 30, 2009
Summary
Bacteriophages, the active agents in lytic broth filtrate, are carried by particles of varying sizes. These phages can detach from larger particles and adsorb onto smaller ones, indicating they are not intrinsically part of the particles themselves.
Area of Science:
- Microbiology
- Biophysics
Background:
- Bacteriophages are viruses that infect bacteria and are utilized in phage therapy.
- Understanding phage behavior in broth filtrates is crucial for optimizing their application.
Purpose of the Study:
- To characterize the physical properties of bacteriophages in lytic broth filtrate.
- To investigate the relationship between bacteriophages and the particles they are associated with.
Main Methods:
- Particle size determination using diffusion rate calculations.
- Fractionation of particles via ultrafiltration.
- Analysis of phage adsorption and desorption dynamics.
Main Results:
- Phage particles in lytic broth filtrate exhibit a wide size range, from 0.6 to 11.4 mmicro in radius, with an average radius of 4.4 mmicro.
- Ultrafiltration allowed for partial separation of particles based on size.
- The active phage agent is adsorbed onto particles and can be redistributed between particles of different sizes.
Conclusions:
- Bacteriophages are transported by particles in broth filtrate, rather than being integral components of these particles.
- Phage-particle interactions are dynamic and can be manipulated experimentally.
- These findings have implications for the formulation and delivery of phage-based agents.
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