91Ó°ÊÓ

When a bacteriophage infects a bacterial or archaeal cell, it can trigger a lytic infection. This type of infection is very aggressive. The virus takes control of the host cell's machinery. It uses the cell to produce copies of itself. During this process, the host cell's normal activities are disrupted. The viral particles accumulate to a point where the host cell can no longer contain them. Eventually, the cell bursts open, a process known as lysis. As a result, new viral particles are released into the surrounding environment. They can then go on to infect new cells and repeat the cycle. Key points about lytic infections:

• Fast and destructive
• Uses the host cell's machinery to make more viruses
• Results in the bursting (lysis) of the host cell, releasing new viruses

Unlike the lytic infection, a lysogenic infection is a more subtle form of viral infection. During this process, the virus does not immediately take over the host cell. Instead, the viral DNA integrates into the host cell's genome. This viral DNA is known as a prophage when it is integrated into the host's DNA. The host cell continues to live and replicate normally, passing on the viral genes to its offspring. The integrated viral DNA can remain dormant for an extended period. However, certain conditions can trigger the prophage to activate and enter the lytic cycle. Key points about lysogenic infections:

• Integration of viral DNA into the host genome
• Viral DNA replicates along with host DNA without harming the cell immediately
• Can remain dormant until activated by specific triggers

A bacteriophage, often referred to as a phage, is a type of virus that specifically infects bacterial and archaeal cells. Bacteriophages have a unique structure and lifecycle tailored to their bacterial hosts. The phage attaches to the surface of a bacterial cell, injecting its genetic material into the host. The lifecycle of a bacteriophage can lead to either a lytic or a lysogenic infection, depending on the viral strategy. Bacteriophages play a crucial role in controlling bacterial populations in various environments. They are also valuable tools in molecular biology research and have potential applications in phage therapy to combat bacterial infections. Key points about bacteriophages:

• Viruses that infect bacteria and archaea
• Can initiate lytic or lysogenic infections
• Important in regulating bacterial populations and research applications