Sunday, March 4, 2012

Reproduction of Bactriophage (Lytic and Lysogenic Cycle)

Information taken from:  http://student.ccbcmd.edu/courses/bio141/lecguide/unit3/index.html#charvir
Note: this post is very poorly written...



Lytic Cycle:
1) Adsorption: the virus attaches to the surface of the host cell
2) Entry: the virus injects its nucleic acid into the bacterial cell
3) Replication: Viral DNA is transcribed and then translated by the host cell.
4) Assembly: The protein parts are then assembled to form new viruses
5) Lysis and Release: the host cell then breaks open, and the viruses are now able to infect other cells

Lysogenic Cycle:
1) Adsorption: the virus attaches to the surface of the host cell
2) Entry
3) Integration: the virus inserts its DNA into the host cell's genome, forming a provirus
4) At this point, whenever the virus undergoes mitosis, the provirus would be replicated as well
5) Spontaneous induction: at some point, the provirus would break out of the host chromosome
6) In each of the infected cells, 3) 4) 5) from the lytic cycle would occur

Advantages/ Disadvantages:
- Lytic cycle is fast is slow, whereas lysogenic is slow
- With the lysogenic cycle, a virus can reproduce more offspring, since the viral DNA is passed onto future generations of the host cell