Final answer:
The word for a virus that infects bacterial cells is a bacteriophage. Bacteriophages use the bacterial cell's machinery to replicate and eventually lyse the cell, releasing new bacteriophages. They can also be used in therapies to treat bacterial infections.
Step-by-step explanation:
The 5-letter word for a virus that infects a bacterial cell is commonly known as a bacteriophage. Bacteriophages bind to the surface receptors of a bacterial cell, and their genome enters the cell without the protein coat. These viruses are highly efficient at taking over the bacterial cell's machinery to produce new virions, replicate, and eventually cause cell lysis, leading to the release of new bacteriophages to infect more bacteria.
Interferons have been found to be particularly useful against viruses, not bacteria. Bacteriophages themselves can be used as a form of therapy to treat bacterial infections by specifically targeting and killing bacterial cells without harming human cells.