Structural analysis of staphylococcal bacteriophage phi 11 attachment sites

Area of Science:

• Microbiology
• Molecular Biology
• Genetics

Background:

• Bacteriophages are viruses that infect bacteria, and their life cycle can involve integration into the host genome.
• Lysogenization is a process where a bacteriophage integrates its DNA into the bacterial chromosome.
• Staphylococcus aureus is a common bacterium, and bacteriophage phi 11 is a specific phage that infects it.

Purpose of the Study:

• To investigate the molecular mechanism of bacteriophage phi 11 lysogenization in Staphylococcus aureus.
• To identify and characterize the DNA sequences involved in the site-specific recombination event during lysogenization.

Main Methods:

• Cloning of DNA segments containing attachment sites from the host chromosome and phage genome.
• Determination of nucleotide sequences of the cloned DNA segments.
• Comparative sequence analysis to identify common regions.

Main Results:

• The DNA segments representing the attachment sites on the Staphylococcus aureus chromosome and the bacteriophage phi 11 genome were successfully cloned and sequenced.
• A very short common sequence of 10 base pairs was identified at the attachment sites.
• The nucleotide sequences of the junctions formed after prophage insertion were also determined.

Conclusions:

• Lysogenization of bacteriophage phi 11 in Staphylococcus aureus is mediated by site-specific recombination.
• The identified 10-base pair common sequence is crucial for the recognition and integration of the phage DNA into the host chromosome.