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Updated: Jul 3, 2026
06:10
Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
Characterization of the mutant lytic state in lambda expression systems.
N Padukone1, S W Peretti, D F Ollis
1Department of Chemical Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA.
Biotechnology and Bioengineering
|February 20, 1992
Summary
Bacteriophage lambda
Area of Science:
- Molecular Biology
- Biotechnology
- Microbiology
Background:
- Bacteriophage lambda's lysogeny and lysis phases offer potential for recombinant expression systems.
- Mutations in lambda vectors enhance product gene stability and beta-galactosidase production.
- Previous systems experienced partial lysis despite genetic modifications.
Purpose of the Study:
- Investigate phage-host cell interactions in productive expression systems.
- Determine the cause of partial lysis in engineered lambda systems.
- Analyze cell growth and morphology changes during induced lytic cycles.
Main Methods:
- Detailed study of the suppressor-free JM105(NM1070) bacteriophage lambda system.
- Monitoring of cell growth, volume, and morphology post-induction.
- Analysis of lambda DNA copy number and endolysin accumulation.
Main Results:
- High beta-galactosidase production (15% of total cell protein) linked to high-copy number lambda DNA.
- Partial lysis observed due to low-level natural suppression of the amber mutation in gene S, causing endolysin accumulation.
- Cells showed a slight increase in number and a 25-fold increase in volume during recombinant protein production.
Conclusions:
- High-copy number lambda DNA drives high recombinant protein yield.
- Endolysin accumulation from partial suppression of amber mutations causes lysis.
- Engineered bacteriophage lambda systems exhibit significant cell volume increase during production.
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