Temperate virus

Temperate Virus

A temperate virus is a type of virus that can exist in two different states within a host cell. These states are the lysogenic cycle and the lytic cycle. The temperate virus is unique in its ability to switch between these two cycles, depending on environmental conditions and the health of the host cell.

Lysogenic Cycle

In the lysogenic cycle, the temperate virus integrates its genetic material into the host cell's DNA. This process is facilitated by an enzyme known as integrase. Once integrated, the viral DNA, now referred to as a prophage, remains dormant within the host cell. The prophage is replicated along with the host cell's DNA whenever the cell divides, effectively spreading the virus without causing immediate harm to the host.

Lytic Cycle

In contrast, the lytic cycle involves the active replication of the virus within the host cell, leading to the eventual destruction of the cell. The temperate virus uses the host cell's machinery to replicate its own genetic material and produce new viral particles. Once the replication process is complete, the newly formed viruses burst out of the host cell, causing its death. This process is known as lysis.

Switching Between Cycles

The ability of a temperate virus to switch between the lysogenic and lytic cycles is a key aspect of its survival strategy. This switch is often triggered by environmental factors or the health of the host cell. For example, if the host cell is under stress or damaged, the virus may switch from the lysogenic to the lytic cycle to ensure its own survival.

Examples of Temperate Viruses

One of the most well-known examples of a temperate virus is the bacteriophage lambda, which infects Escherichia coli bacteria. Other examples include the herpes simplex virus, which can cause cold sores and genital herpes in humans, and the Epstein-Barr virus, which is associated with several types of cancer.

See Also

• Virus
• Lysogenic cycle
• Lytic cycle
• Bacteriophage
• Herpes simplex virus
• Epstein-Barr virus