Viruses lysogeny

The lytic growth cycle Lysogeny 11 The human immunodeficiency virus... 

Marie, D., Bmssaard, C. P. D., Thyrhaug, R., Bratbak, G., and VarJot, D. (1999). Enumeration of marine viruses in culture and natural samples by flow cytometry. Appl. Environ. Microbiol. 65, 45—52. McDaniel, L., and Capone, D. G. (1985). A comparison of procedures for the separation of aquatic bacteria from sediments for subsequen direct enumeration. J. Microbiol. Methods 3, 291—302. McDaniel, L., Houchin, L. A., Williamson, S. J., and Pard, J. H. (2002). Lysogeny in marine Synechococcus. Nature 415, 496. 

Weinbauer, M. G., Brettar, I., and Hofle, M. G. (2003). Lysogeny and virus-induced mortality of bacterioplankton in surface, deep, and anoxic marine waters. Limnol. Oceanogr. 48, 1457—1465. 

Viruses do not always lyse their host cells, however. A separate process called lysogeny involves the incorporation of the viral DNA into the host chromosome. Simian virus 40 (SV40) is an example of a DNA virus. It appears to be... 

Reflect and Apply Some viruses can undergo lysis or lysogeny even in the same host. What might be a reason for this Under what conditions might the virus favor the one strategy over the other ... 

Viruses can often switch from one pathway to another, based on the condition of the host cells. If the host is healthy, there is sufficient material to allow the virus to replicate and to produce new virions. If the host cell is starved or unhealthy, there may be insufficient energy and material to do so. In this case, lysogeny allows the DNA to incorporate in the host cell, where it can wait until the cell s health improves. 

Dybwig K, Maniloff J. Integration and lysogeny by an enveloped mycoplasma virus. J Gen Virol. 1983 64 1781-5. 

Lysogeny allows temperate viruses to survive and replicate within a limited population of cells that are protected from further infection. On the other hand, the survival of virulent bacteriophages depends on the continuous availability of susceptible bacteria, e.g. in sewage. 

Lysogeny The process whereby viral DNA is incorporated into the bacterial genome, resulting in transmission of the virus upon reproduction. 

Lysogeny The ability of temperature bacteriophages to persist in a bacterium by the integration of the viral DNA into the host chromosome and without the replication of new viruses or cell lysis. 

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