Morphological, host range, and genetic characterization of two coliphages.

Area of Science:

• Microbiology
• Virology
• Genetics

Background:

• Coliphages are viruses that infect bacteria, specifically Escherichia coli.
• Understanding phage characteristics is crucial for potential applications in biotechnology and medicine.

Purpose of the Study:

• To characterize two coliphages, AR1 and LG1, based on their morphology, host range, and genetic properties.
• To assess the potential of these phages as biocontrol or diagnostic agents.

Main Methods:

• Transmission electron microscopy for morphological analysis.
• Host range testing on various Escherichia coli serotypes and other enterobacteria.
• Genome size determination and restriction endonuclease analysis.
• Southern hybridization for genetic relatedness assessment.

Main Results:

• Both AR1 and LG1 belong to the Myoviridae family, with distinct head and tail dimensions.
• Phages demonstrated broad infectivity against multiple E. coli serotypes and some other enterobacteria like Proteus mirabilis, Shigella dysenteriae, and Salmonella.
• Genome sizes were 150 kb for AR1 and 49.5 kb for LG1.
• AR1 shares genetic similarities with phage T4, indicated by restriction enzyme digestion and Southern hybridization.

Conclusions:

• AR1 and LG1 are well-characterized coliphages with significant potential for practical applications.
• Their wide host ranges suggest utility as biocontrol agents against E. coli in food and animal husbandry.
• These phages could also serve as diagnostic tools for detecting E. coli prevalence.