Abstract
1. We have obtained various kinds of virulent mutant from temperate phage s2 liberated from lysogenic strain, S. typhimurium 4066. Three strains of the virulent mutant of which virulence grade is variant and which can be clearly differentiated on the plaque were taken for study.
2. In order to examine the arrangement of four loci (tu, v2, vw, vs) upon the chromosome of phage, a recombination test by single cell burst experiment among each phage has been carried out and the recombinant value has been calculated as below: tu×vs: 8.95, tu×vw: 8.32, V2×vs: 1.35. Accordingly, linkage map of S. typhimurium 4066 phage which tu, v2, vw, vs, were arranged upon one line at certain intervals was drawn.
3. From the result of above experiment, we studied a genetic observation on virulent mutation of temperate phage.
