TO INVESTIGATE THE VARIETY OF BACTERIAL MUTANTS OCCURING SPONTANEOUSLY AND PRODUCED BY VARIOUS RADIATIONS AND CHEMCALS
Final technical rept. 1 Oct 1961-30 Sep 1962
TRINITY COLL DUBLIN (IRELAND)
Pagination or Media Count:
An account of studies on strains of Salmonella typhimrium which show instability at particular loci is given. The more extensive study was on the locus that suppresses the requirement for leucine of strain leu 151. Instability was shown to occur at different sites in this suppressor locus in different strains. The site of instability can undergo forward and backward mutation the instability being retained at the site through these successive mutations. The instability can change from one locus to another, but it is not always accompanied by the loss of instability from the suppressor of leucine requirement. These and related observations are interpreted in terms of units that attach to the loci. By analogy with controlling episomes in maize, they are called controlling episomes.