coliphages

Coliphages are viruses that infect bacteria, specifically those belonging to the genus Escherichia (E. coli). The name "coliphage" is derived from "E. coli" and the Greek word "phagein," meaning "to eat," reflecting their ability to lyse or destroy host bacteria. They are a type of bacteriophage, a broad category of viruses that target bacteria.

Coliphages are ubiquitous in the environment, commonly found in soil, sewage, and the intestinal tracts of animals, including humans. Their presence in water sources is often used as an indicator of fecal contamination, as E. coli is a common inhabitant of mammalian intestines.

Structurally, coliphages vary widely but often possess a distinct head-tail morphology. The head contains the viral genetic material (DNA or RNA), and the tail is used for attachment to and injection of this genetic material into the host bacterium.

The life cycle of a coliphage typically involves adsorption to the bacterial cell surface, penetration of the bacterial cell wall, replication of viral genetic material and proteins within the host, assembly of new phage particles, and finally, lysis of the host cell, releasing progeny phages to infect new bacteria.

Coliphages have significant applications in various fields. They are used as indicators of microbial water quality and in the development of phage therapy, an alternative or adjunct to antibiotics for treating bacterial infections. Research into coliphage biology also contributes to our understanding of viral evolution and gene expression.