The genetic control of dissimilatory pathways in Pseudomonas putida.

WE shall present here an analysis of the linkage relationhsips among structural genes that control steps of the /3-ketoadipate pathway and two other dissimilatory pathways in a fluorescent pseudomonad, Pseudomonas putida. The convergent branches of the p-ketoadipate pathway (Figure 1 ) , which exists in many taxonomic groups of aerobic bacteria, provide a means for the conversion of certain aromatic and hydroaromatic compounds to intermediates of the tricarboxylic acid cycle. The initial points of metabolic convergence are two diphenolic intermediates, catechol and protocatechuic acid: each primary substrate is oxidized to one of these intermediates through a special reactionsequence. We shall designate such peripheral sequences by their primary substrates: thus, the mandelate sequence comprises the set of reactions by which mandelic acid is oxidized to catechol. Catechol and protocatechuic acid are further metabolized through parallel, convergent sequences to the end-lactone of p-keto-