Genetic serologic, and biochemical studies on viral infection and lysogenization

摘要

Salmonella phage c15 undergoes a two-way host-controlled variation.nFhage e15 [A] plates with low EOP on strain I-1 and vice versa. Be sides multiplicity activation (MA), a thermolabile factor responsible for phage growth restriction has been found. Experiments with p32_ labeled phages show that the DNA of the restricted phage is degraded rapidly after injection of the nonpermissive host, and that this degradation is prevented by heating the host cells prior to infection. Most probable explanation would be that thermolabile, DNA destroying, and MA-responsible factors are identical with each other.nChemical, serological, virological, and genetic studies have re vealed the followings: Salmonella senftenberg 87Aa' with G-antigen 3 alone has galactosyl-mannosyl-rhamnose as serological determinant; specificity of group E Salmonellas is determined by mannosyl-rham-nose; another cross reaction between El strains- and 87Aa' is also attributed to the resemblance in chemical structures; 87Aa' is suspected to carry defective prophase e15 lacking conversion genes. Receptors for e15 and C341 are suggested to be related to galactosyl and acetyl-galactosyl structure, respectively.