Isolation of the bacteriophage lambda receptor from Escherichia coli

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Background:

• Bacteriophages, like phage lambda, are viruses that infect bacteria.
• Bacterial outer membranes play crucial roles in cell-surface interactions.
• Understanding phage-host interactions is vital for controlling bacterial infections.

Purpose of the Study:

• To identify and characterize the factor responsible for phage lambda inactivation in Escherichia coli.
• To determine the location and function of this factor in phage lambda adsorption.

Main Methods:

• Extraction of inactivating factors from Escherichia coli.
• Fractionation and partial purification of the protein factor.
• Testing the effect of the purified factor on phage lambda viability and DNA integrity.

Main Results:

• A protein factor inactivating phage lambda was successfully extracted from E. coli.
• This protein was localized to the outer membrane of the bacterial envelope.
• The factor was present in phage-sensitive strains but absent in resistant strains, indicating its role as the lambda receptor.
• Purified receptor caused phage inactivation and deoxyribonucleic acid release.

Conclusions:

• The identified protein is the lambda receptor, crucial for phage lambda adsorption to E. coli.
• The lambda receptor mediates the initial step in phage infection by binding the phage.
• This interaction leads to phage inactivation and subsequent release of phage genetic material.