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Published on: October 14, 2011
Prophage-Cured Derivatives of Streptococcus lactis and Streptococcus cremoris
1National Institute for Research in Dairying, Shinfield, Reading, Berkshire RG2 9AT, England.
Applied and Environmental Microbiology
|November 1, 1980
Summary
Prophage curing in Streptococcus lactis and cremoris created phage indicators. Reintroducing phages confirmed the lysogenic state in these lactic streptococci, a significant finding.
Area of Science:
- Microbiology
- Bacteriology
- Molecular Biology
Background:
- Bacteriophages are viruses that infect bacteria.
- Lysogeny is a state where a bacteriophage integrates its genome into the host bacterium's genome.
- Lactic streptococci are important bacteria in dairy fermentation.
Purpose of the Study:
- To achieve prophage curing in Streptococcus lactis and Streptococcus cremoris.
- To demonstrate the lysogenic state in lactic streptococci.
- To develop indicator strains for temperate bacteriophages.
Main Methods:
- Prophage curing using specific induction methods.
- Testing cured strains for sensitivity to temperate bacteriophages.
- Relysogenization experiments to re-establish the lysogenic state.
Main Results:
- Successful isolation of prophage-cured Streptococcus lactis and Streptococcus cremoris strains.
- Cured derivatives effectively detected the presence of their corresponding temperate bacteriophages.
- Demonstration of the lysogenic cycle through successful relysogenization.
Conclusions:
- Prophage curing provides a method to generate indicator strains for bacteriophages in lactic streptococci.
- This study provides the first formal evidence of the lysogenic state in lactic streptococci.
- The findings have implications for understanding phage-host interactions in dairy starter cultures.
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