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Intergration of the receptor for bacteriophage lambda in the outer membrane of Escherichia coli: coupling with cell
Abstract:
Induction of the synthesis of the receptor for phage lambda is obtained by adding maltose and adenosine 3'-5'-cyclic monophosphate to glucose grown cells of Escherichia coli. Bacteria induced for a short period of time were infected with a high multiplicity of phage lambda , and examined under the electron microscope. Only a fraction of the bacteria were seen to have adsorbed a large number of phage particles. The majority of such bacteria had a constriction indicating formation of a septum, and, in this case, the density of adsorbed particles was highest in the vicinity of the constriction. When found on bacteria showing no sign of septum formation, the adsorbed particles were asymmetrically distributed, one pole of the bacteria being more heavily covered with phage particles than the other. Such asymetrically covered bacteria are believed to have originated from cells which divided during the induction period. The results suggest that the receptor for phage lambda, a protein of the outer membrane, is integrated in the cell envelope during the last quarter of each generation and that the integration process is initiated in the vicinity of the forming septum.
Insights
Synthesis of the phage lambda receptor in Escherichia coli is induced by maltose and cyclic AMP. This outer membrane protein integrates into the cell envelope near the septum during the cell cycle.
Area of Science:
- Microbiology
- Molecular Biology
- Cell Biology
Background:
- The receptor for phage lambda is a key outer membrane protein in Escherichia coli.
- Understanding its synthesis and integration is crucial for bacterial genetics and phage-host interactions.
Purpose of the Study:
- To investigate the timing and location of phage lambda receptor integration into the Escherichia coli cell envelope.
- To elucidate the relationship between receptor synthesis and cell division.
Main Methods:
- Induction of receptor synthesis using maltose and cyclic AMP in glucose-grown E. coli.
- Infection with phage lambda and subsequent electron microscopy analysis.
- Observation of phage particle adsorption patterns in relation to cell septum formation.
Main Results:
- Phage lambda particles preferentially adsorbed to areas near the cell septum.
- Asymmetrical phage distribution was observed on bacteria without septa, suggesting integration during division.
- The phage lambda receptor is an outer membrane protein.
Conclusions:
- The phage lambda receptor integrates into the cell envelope during the final quarter of the cell cycle.
- Receptor integration is initiated near the forming septum.
- This process is linked to cell division in Escherichia coli.