Lytic cycle
From Wikipedia, the free encyclopedia
Jump to: navigation, search ...
Lytic cycle
The lytic cycle is one of the two cycles of viral reproduction, the other being the lysogenic cycle. These cycles should not, however, be seen as discrete and separate, but rather as somewhat interchangeable.
Lytic cycle
The development of a bacteriophage, either after infection of a host bacterium or after induction of a prophage, resulting in production and release of free progeny phage particles, and lysis of the host cell.
lytic cycle
(lit-ik)
A type of viral replication cycle resulting in the release of new phages by death or lysis of the host cell.
The lytic cycle is one in which the virus takes over operation of the bacterium immediately upon entering it, with the production of new viruses and their subsequent release destroying the bacterium.
Mechanistically, these enzymes are very well characterized: they share a common catalytic cycle that involves formation of a two-electron oxidized intermediate (Compound I) followed by reduction of Compound I by substrate.
The lytic cycle occurs when the viral DNA immediately takes over the host cell (remember that viruses are obligate intracellular parasites) and begins making new viruses.
Lysogeny
In some cases, though, the events of the lytic cycle are not completed. E. coli infected by a DNA bacteriophage may resume its normal existence, including reproducing itself.
Where has the virus gone?
that functions as a cofactor in dehydrogenase enzymes; linked covalently to specific lysine residues in enzyme proteins, it can exist as the reduced open-chain form or the closed-ring disulfide form, undergoing interconversion in a catalytic cycle.
 See also: Enzyme, Trans, Lysis, Cell, Bacteria
|
