bakteriofág

Bakteriofág, often shortened to phage, is a type of virus that infects and replicates within bacteria and archaea. The term "bacteriophage" literally means "bacteria eater." Phages are ubiquitous, found in all environments where bacteria exist, including soil, water, and even the human gut. They are highly specific, typically infecting only certain strains of bacteria.

The life cycle of a bacteriophage generally involves two main pathways: the lytic cycle and the lysogenic cycle. In the lytic cycle, the phage attaches to a host bacterium, injects its genetic material, and hijacks the bacterial machinery to produce new phage particles. Eventually, the host cell is lysed, releasing the newly formed phages to infect other bacteria. In the lysogenic cycle, the phage's genetic material integrates into the bacterial chromosome, becoming a prophage. This integrated phage DNA is replicated along with the bacterial DNA during cell division. Under certain conditions, the prophage can enter the lytic cycle.

Bacteriophages have been explored for various applications, most notably as a potential alternative to antibiotics in phage therapy. This approach leverages the specificity of phages to target and eliminate pathogenic bacteria without harming beneficial microbes. Research is ongoing to overcome challenges related to phage resistance and delivery for widespread clinical use. Phages are also valuable tools in molecular biology research, used for genetic engineering and as model systems to study viral replication and gene expression.