Question

Describe the temporal sequence of the bacteriophage life cycle.

Short answer

Question: Briefly describe the temporal sequence of the bacteriophage life cycle, mentioning the key stages involved. Answer: The bacteriophage life cycle consists of five key stages: 1) Attachment, where the bacteriophage binds to a specific receptor on the bacterial host cell; 2) Injection of genetic material into the host cell; 3) Replication of the viral genetic material using the host cell's biochemical machinery; 4) Assembly of the individual viral components into new, complete bacteriophages; and 5) Release of the bacteriophages from the host cell generally through cell lysis.

Step-by-step solution

Attachment

The bacteriophage first attaches to the surface of the host bacterial cell using its tail fibers. Binding to a specific receptor site on the bacterial cell wall ensures that the bacteriophage only infects the target bacterial species.

Injection of Genetic Material

Once attached, the bacteriophage injects its genetic material, either DNA or RNA, into the host cell. This involves using the bacteriophage's tail structure to achieve a connection with the bacterial cell membrane, which then acts as a conduit for the passage of genetic material.

Genetic Material Replication

Within the host cell, the viral genetic material takes control of the bacterial cell's biochemical machinery, forcing it to produce nucleotides and proteins required for the replication of the bacteriophage's genetic material. This process is essentially hijacking the host cell for the purposes of creating new viral particles.

Viral Assembly

Once enough viral components have been synthesized, the next step is the assembly of these individual parts into new, complete bacteriophages. This might involve the formation of a capsid around the viral genetic material, as well as the development of tail fibers and other structural components necessary for infectivity.

Release of Bacteriophages

Finally, the newly assembled bacteriophages are released from the host cell. This generally occurs through cell lysis, in which the host cell's membrane is ruptured, allowing the new viral particles to escape and infect other bacterial cells. This process might be facilitated by the production of specific enzymes that weaken the bacterial cell wall, thus leading to cell lysis and the release of the new bacteriophages.