Bacterium infection and bacteriophages Bacterium infection and bacteriophages Bacteriophages, also known as phages, are viruses that attack bacteria. Phages are among the most complex viruses.
Many phages have a tail attached to the head.
The phage may use fibers extending from the tail to attach to a bacterium. A viral reproductive cycle can be lytic or temperate. When the virus infects a susceptible host cell, it forces the host to use its metabolic machinery to replicate viral particles. The virus attaches to receptors on the host cell wall. The nucleic acid of the virus moves through the plasma membrane and into the cytoplasm of the host cell.