Lysogenic cycle, compared to lytic cycle

Lysogeny, or the lysogenic cycle, is one of two methods of viral reproduction (the lytic cycle is the other). Lysogeny is characterized by the fusion of the nucleic acid of a bacteriophage with that of a host bacterium. The newly integrated genetic material, called a prophage can be transmitted to daughter cells at each subsequent cell division, and a later event (such as UV radiation) can release it, causing proliferation of new phages via the lytic cycle. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... The lytic cycle is one of the two cycles of viral reproduction, the other being the lysogenic cycle. ... An artists rendering of an Enterobacteria phage T4. ... A phage genome inserted as part of the linear structure of the DNA chromosome of a bacterium. ... For other uses, see Ultraviolet (disambiguation). ...

Mixed cycles

Following are some types of viruses that replicate by the lysogenic cycle, but also partly by the lytic cycle.

Bacteriophages

Some DNA phages, called temperate phages, only lyse a small fraction of bacterial cells; in the remaining majority of the bacteria, the phage DNA becomes integrated into the bacterial chromosome and replicates along with it. In this lysogenic state, the information contained in the viral nucleic acid is not expressed. The model organism for studying lysogeny is the lambda phage. Roughly 50-60 nucleotides are taken out of the lysogenic pathway and used. The structure of part of a DNA double helix Deoxyribonucleic acid, or DNA, is a nucleic acid molecule that contains the genetic instructions used in the development and functioning of all known living organisms. ... A bacteriophage (from bacteria and Greek phagein, to eat) is a virus that infects bacteria. ... Enterobacteria phage λ (lambda phage) is a temperate bacteriophage that infects Escherichia coli. ...

Herpes simplex virus

The Herpes simplex virus first enters the lytic cycle after infecting a human, then the lysogenic cycle before travelling to the nervous system where it resides in the nerve fibers as an episomal element. After a long period of time (months to years) in a latent stage, the herpes virus is often reactivated to the lytic stage, during which it may cause disease symptoms similar to those experienced during the initial infection. Species Herpes simplex virus 1 (HSV-1) Herpes simplex virus 2 (HSV-2) This article is about the virus. ... Figure 1: Illustration of a bacterium with plasmids enclosed showing chromosomal DNA and plasmids. ...

Lysogenic conversion

In some interactions between lysogenic phages and bacteria, lysogenic conversion may occur. It is when a temperate phage induces a change in the phenotype of the bacteria infected that is not part of a usual phage cycle. Changes can often involve the external membrane of the cell by making it impervious to other phages or even by increasing the pathogenic capability of the bacteria for a host. This article or section does not cite its references or sources. ... Individuals in the mollusk species Donax variabilis show diverse coloration and patterning in their phenotypes. ... Phyla Actinobacteria Aquificae Chlamydiae Bacteroidetes/Chlorobi Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Lentisphaerae Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Verrucomicrobia Bacteria (singular: bacterium) are unicellular microorganisms. ...

Examples:

• Corynebacterium diphtheriae produces the toxin of diphtheria only when it is infected by the phage β. In this case, the gene that codes for the toxin is carried by the phage, not the bacteria.
• Vibrio cholerae is a non-toxic strain that can become toxic, producing cholera toxin, when it is infected with the phage CTXφ.
• Clostridium botulinum causes botulism.
• Streptococcus pyogenes causes scarlet fever.
• Shiga toxin
• Tetanus

Extra genes present in prophage genomes which do not have a phage function but (may) act as fitness factors for the lysogen are termed "morons".^[1] Binomial name Kruse, 1886 Corynebacterium diphtheriae is a pathogenic bacterium that causes diphtheria. ... An artists rendering of an Enterobacteria phage T4. ... Binomial name Vibrio cholerae Pacini 1854 Vibrio cholerae is a gram negative bacterium with a curved-rod shape that causes cholera in humans. ... Drawing of Death bringing the cholera, in Le Petit Journal. ... Binomial name van Ermengem, 1896 Clostridium botulinum is a bacterium that produces the toxin botulin, the causative agent in botulism. ... Botulism (Latin, botulus, sausage) is a rare, but serious paralytic illness caused by a nerve toxin, botulin, that is produced by the bacterium Clostridium botulinum. ... Binomial name Streptococcus pyogenes Rosenbach 1884 Streptococcus pyogenes is a Gram-positive coccus that grows in long chains depending on the culture method. ... Shiga toxins are a family of related toxins with two major groups, Stx1 and Stx2, whose genes are considered to be part of the genome of lambdoid prophages. ... Tetanus is a medical condition that is characterized by a prolonged contraction of skeletal muscle fibers. ... A lysogen or lysogenic phage is a phage that does not go into a lytic cycle but instead either integrates into the host bacterias chromosome or lives as a stable plasmid within the host cell. ...

References

1. ^ Canchaya C, Proux C, Fournous G, Bruttin A, Brüssow H (2003). "Prophage genomics". Microbiol. Mol. Biol. Rev. 67 (2): 238-76. PMID 12794192.