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Updated: Jun 1, 2026
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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
Single-phage profiling illuminates viral individuality during bacterial cell fate determination
Ehsan Homaee1,2, Wenqing Zhu1,3,4, Tianyou Yao1
1Department of Physics, University of Illinois Urbana-Champaign, Urbana, IL, USA.
Nature Communications
|May 30, 2026
Summary
Bacteriophage lambda infection in E. coli reveals that individual phage transcription dictates cell fate. Consensus phage activity is required for cell dormancy (lysogeny), while lytic cells can harbor dormant phages.
Area of Science:
- Microbiology and Virology
- Systems Biology
- Molecular Genetics
Background:
- Bacteriophage infection presents a choice between host cell lysis or viral dormancy (lysogeny).
- This decision drives cellular heterogeneity within genetically identical populations.
- Individual viral transcriptional activity within a cell has been empirically challenging to study.
Purpose of the Study:
- To investigate the transcriptional activity of individual bacteriophages during infection.
- To understand how single-phage behavior contributes to whole-cell fate decisions (lysis vs. lysogeny).
- To explore the role of intracellular viral replication in determining host cell fate.
Main Methods:
- Utilized parallel sequential fluorescence in situ hybridization (par-seqFISH) for high-resolution transcript profiling.
- Employed spatial clustering of phage-encoded transcripts within individual Escherichia coli cells.
- Analyzed synchronized infections of E. coli with bacteriophage lambda.
Main Results:
- Whole-cell transcription kinetics correlate with the lysis/lysogeny fate decision.
- Intracellular viral replication is essential for the divergence of cell fate decisions.
- Single-phage analysis revealed variability in viral activity; lytic cells can contain phages with lysogenic activity.
Conclusions:
- Consensus among coinfecting phages appears necessary for establishing cell dormancy (lysogeny).
- Individual phage transcriptional individuality exists, even within the same infected cell.
- Understanding whole-cell behavior requires examining the activity of distinct genetic circuit copies.
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