RADIOBIOLOGICAL STUDIES ON PHAGE INDUCTION IN LYSOGENIC STRAINS (II)

Observations on phage output and on anaerobic lysis of lysogenic strains of Bacillus megatherium.

The phenomenon of lysogenicity is an interesting aspect of the bacteriumbacteriophage relationship, for this is an instance of host cells capable of carrying virus through an infinite succession of subcultures, even through cycles of sporulation (den Dooren de Jong, 1930, 1932). Unlike other bacterium-bacteriophage systems, infection of the host does not inevitably terminate in its destruction;...

Induction of the lysogenic phage encoding cholera toxin in naturally occurring strains of toxigenic Vibrio cholerae O1 and O139.

In toxigenic Vibrio cholerae, the CTX genetic element which carries the genes for cholera toxin (CT) is the genome of a lysogenic bacteriophage (CTXPhi). Clinical and environmental strains of V. cholerae O1 or O139 and stools that were culture positive for cholera were analyzed to study the induction and transmission of CTXPhi. To our knowledge, this is the first report of the examination of CT...

Appearance of New Phage Types and New Lysogenic Strains after Adaptation of Lysogenic B. Megatherium to Ammonium Sulfate Culture Medium

1. Lysogenic B. megatherium 899a was adapted to growth in a minimal ammonium sulfate medium (ASCM). 2. Adaptation took place slowly and the following changes in the culture occurred: (a) The growth rate increased from 0.5 to 1.5-2.0/hr. (b) The culture changed from diffuse to mucoid. (c) The total phage titer, and the gelatinase concentration decreased to 1/100 or less. (d) The types of phage p...

Studies on Bacteriophage Typing of Staphylococci Isolated from Bovine Milk : Ii. Some Observations on the Lysogenic Strains

Studies on Bacteriophage Typing of Staphylococci Isolated from Bovine Milk : Ii. Some Observations on the Lysogenic Strains