BIOCHEMICAL AND GENETIC GROUPING OF ISOLEUCINE-VALINE MUTANTS OF PSEUDOMONAS AERUGINOSA.

Pearce, L. E. (University of Otago, Dunedin, New Zealand), and J. S. Loutit. Biochemical and genetic grouping of isoleucine-valine mutants of Pseudomonas aeruginosa. J. Bacteriol. 89:58-63. 1965.-Isoleucine- and valine-requiring mutants of Pseudomonas aeruginosa, induced with ultraviolet and ethyl-methane-sulfonate, were isolated. The feeding properties and growth requirements of 56 of these mutants were examined, and evidence was found for at least four phenotypic groups, A, B, C, and D, controlling the biosynthesis of isoleucine and valine. Preliminary genetic mapping by use of bacteriophage-mediated transduction showed linkage between the mutant loci within groups A, B, and C. There was also evidence of linkage between the genes controlling groups A and B and some slight evidence of linkage between the other groups. There was insufficient evidence to suggest the arrangement of the genes.