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Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
Following cell-fate in E. coli after infection by phage lambda
1Department of Physics, University of Illinois at Urbana-Champaign, USA. lzeng@illinois.edu
Journal of Visualized Experiments : Jove
|October 26, 2011
Summary
Researchers developed a method to fluorescently label bacteriophages (phages) for real-time observation of bacterial cell-fate determination. This technique allows detailed analysis of phage lambda and E. coli interactions, revealing lysis or lysogeny outcomes.
Area of Science:
- Microbiology
- Molecular Biology
- Systems Biology
Background:
- The bacteriophage (phage) lambda and E. coli system is a model for understanding cell-fate decisions.
- Phage infection leads to either a lytic (virulent) or lysogenic (dormant) pathway.
Purpose of the Study:
- To detail a procedure for creating fluorescent phages and observing bacterial infection dynamics in real-time.
- To enable the study of individual phage-cell interactions and their outcomes.
Main Methods:
- Development of hybrid phages co-expressing wild-type and YFP-fusion capsid proteins.
- Purification, DAPI-labeling, and quality control of fluorescent phage stocks.
- Microscopic observation of phage-infected E. coli over 4 hours with time-lapse imaging in multiple channels.
Main Results:
- Real-time tracking of ~100 individual phage-E. coli infections per experiment.
- Distinguishing between lytic (green fluorescence, cell lysis) and lysogenic (red fluorescence, cell growth) pathways.
- Automated and manual analysis to identify infection parameters and outcomes.
Conclusions:
- The described method provides a powerful tool for dissecting phage-host interactions at the single-cell level.
- Enables quantitative analysis of cell-fate determination in microbial systems.
- Facilitates deeper understanding of viral life cycles and host responses.
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