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Updated: Jul 11, 2026
06:10
Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
Subclassification and targeted characterization of prophage-encoded two-component cell lysis cassette
K V Srividhya1, S Krishnaswamy
1Centre of Excellence in Bioinformatics, School of Biotechnology, Madurai Kamaraj University, Madurai 625 021, India.
Journal of Biosciences
|October 5, 2007
Summary
Bacteriophage lysis involves holin and lysozyme. Researchers identified 47 prophages with lysis genes, including holin (essd) and endolysin (ybcS) from DLP12, crucial for bacterial evolution.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Bacteriophage-induced cell lysis is mediated by holin-lysozyme systems.
- Prophages, integrated bacteriophages, contribute to bacterial genome evolution.
- A prophage database identified 47 prophages associated with putative cell lysis genes.
Purpose of the Study:
- To characterize the two-component cell lysis cassette from the defective lambdoid prophage DLP12.
- To investigate the structure-function relationship of holin (essd) and endolysin (ybcS) proteins.
- To understand the role of prophage-encoded lysis proteins in bacterial evolution.
Main Methods:
- Database analysis of prophages and associated lysis genes.
- Bioinformatic analysis of holin and endolysin protein structures.
- Gene expression, protein overexpression, and purification in Escherichia coli.
- Biochemical assays to determine endolysin lytic activity.
Main Results:
- Identified 47 prophages with putative lysis genes, clustering into four subgroups.
- The DLP12 prophage encodes holin (essd) and endolysin (ybcS) similar to functional bacteriophage lysis genes.
- Holin essd exhibits characteristics of class II holins, including a dual start motif and transmembrane regions.
- Endolysin ybcS possesses an N-terminal SAR domain and demonstrates lytic activity against bacterial cell wall substrates.
Conclusions:
- The characterized holin and endolysin from DLP12 are functional components of a cell lysis cassette.
- These findings highlight the potential contribution of cryptic prophage proteins to bacterial evolution.
- Further structure-function studies of prophage-encoded proteins are essential for understanding bacterial adaptation.
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