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Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
STUDIES ON THE PURIFICATION OF BACTERIOPHAGE
G Kalmanson1, J Bronfenbrenner
1Department of Bacteriology and Immunology, Washington University School of Medicine, St. Louis.
The Journal of General Physiology
|October 30, 2009
Summary
Researchers developed a method to concentrate and purify bacteriophage, revealing its protein nature and variable particle sizes. This purified bacteriophage can stimulate antibody production, offering insights into phage structure and function.
Area of Science:
- Microbiology
- Virology
- Biochemistry
Background:
- Bacteriophage purification is crucial for studying their structure and function.
- Previous methods were insufficient for obtaining pure, active bacteriophage preparations.
- Understanding bacteriophage composition is key to their application in therapy and research.
Purpose of the Study:
- To develop a simple and effective method for concentrating and purifying bacteriophage.
- To characterize the physical and chemical properties of purified bacteriophage.
- To investigate the size distribution and molecular weight of bacteriophage particles.
Main Methods:
- Utilized reinforced collodion membranes for selective retention of bacteriophage.
- Employed a synthetic medium with ammonia for bacteriophage proliferation and purification.
- Concentrated bacteriophage using suction and purified via extensive washing.
- Determined nitrogen content and protein color tests for purified bacteriophage.
- Measured diffusion rates and ultrafiltration through collodion membranes to assess particle size.
Main Results:
- A method was established to concentrate and purify bacteriophage, yielding an active agent.
- Purified bacteriophage is labile, losing activity upon drying, and contains protein.
- Calculated molecular weights ranged from approximately 25,000 to 36,000,000, with particle radii from 2 to 22 millimicra.
- Staphylococcus bacteriophage purification yielded similar results regarding particle size distribution.
- The active principle exists as particles of varying sizes, with smaller particles exhibiting full bacteriophage properties.
Conclusions:
- The developed method effectively concentrates and purifies bacteriophage.
- Bacteriophage consists of proteinaceous material with a wide range of particle sizes.
- Larger particles are likely aggregates or inactive colloids with adsorbed active phage.
- Purified bacteriophage acts as an antigen, stimulating antibody production.
- Further research into bacteriophage structure and antigenicity is warranted.
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