Biomaterial Database

Infection by bacteriophage P1 and development of host-controlled restriction and modification and of lysogenic immunity. 1969

E R Werner, and J R Christensen

Shigella dysenteriae cells were infected with phage P1 or P1cl. The outcome of superinfection of these cells with phage T1.Sh or T1.Sh(P1) or P1cl was studied as a function of time after the initial infection. Cells undergoing either a lytic response or a lysogenic response to the primary infection develop the ability to specifically restrict T1.Sh between 30 and 45 min. Between 15 and 30 min, the cells seem to develop the ability to produce T1.Sh(P1) after infection by T1.Sh. However, reasons are given for believing that this apparent time difference is consistent with a simultaneous development of the two capacities (restriction and modification) within the cell. This development occurs between 30 and 45 min. Cells infected with P1cl and superinfected 45 or more min later with T1.Sh(P1) can yield both P1cl and T1. Cells infected with P1 become resistant to infection by P1cl within 5 to 10 min. It is argued that this early immunity is not necessarily different in mechanism from true lysogenic immunity.

UI	MeSH Term	Description	Entries
D008242	Lysogeny	The phenomenon by which a temperate phage incorporates itself into the DNA of a bacterial host, establishing a kind of symbiotic relation between PROPHAGE and bacterium which results in the perpetuation of the prophage in all the descendants of the bacterium. Upon induction (VIRUS ACTIVATION) by various agents, such as ultraviolet radiation, the phage is released, which then becomes virulent and lyses the bacterium.	Integration, Prophage,Prophage Integration,Integrations, Prophage,Prophage Integrations
D005827	Genetics, Microbial	A subdiscipline of genetics which deals with the genetic mechanisms and processes of microorganisms.	Microbial Genetics,Genetic, Microbial,Microbial Genetic
D001435	Bacteriophages	Viruses whose hosts are bacterial cells.	Phages,Bacteriophage,Phage
D012762	Shigella dysenteriae	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that is extremely pathogenic and causes severe dysentery. Infection with this organism often leads to ulceration of the intestinal epithelium.	Bacillus dysenteriae,Bacillus dysentericus,Bacillus shigae,Eberthella dysenteriae,Shigella shigae
D014762	Viral Interference	A phenomenon in which infection by a first virus results in resistance of cells or tissues to infection by a second, unrelated virus.	Interference, Viral,Interferences, Viral,Viral Interferences