Genetic map of the Staphylococcal bacteriophage phi11

Area of Science:

• Microbiology
• Molecular Biology
• Genetics

Background:

• Bacteriophages, such as staphylococcal bacteriophage phi 11, are viruses that infect bacteria and play crucial roles in microbial ecosystems and genetic transfer.
• Understanding the genetic organization and functional genes of bacteriophages is essential for various applications, including phage therapy and genetic engineering.

Purpose of the Study:

• To construct a genetic map of the staphylococcal bacteriophage phi 11 using three-factor cross experiments.
• To identify and characterize genes involved in bacteriophage head and tail formation.
• To investigate the genomic contribution of bacteriophage phi 11 to a plasmid-phage hybrid, phi 11 de.

Main Methods:

• Utilized ten sus mutants of bacteriophage phi 11, each representing a distinct complementation group.
• Performed three-factor cross experiments to determine gene order and construct a genetic map.
• Conducted functional studies involving electron microscopic examination of bacterial lysates after prophage induction or infection.

Main Results:

• Established a circular genetic map for bacteriophage phi 11.
• Identified one early gene, five genes involved in tail formation, and three genes involved in head formation.
• Determined that the plasmid-phage hybrid phi 11 de contains most late genes but lacks a continuous phi 11 segment including an early gene and flanking late genes.

Conclusions:

• The genetic map of bacteriophage phi 11 is circular, with distinct genes responsible for essential functions like head and tail morphogenesis.
• The genomic organization of phi 11 de indicates a specific deletion of an early gene and adjacent late genes from the parental phi 11 genome.
• These findings contribute to a deeper understanding of bacteriophage genetics and genome evolution.