Characterization of a benzoate permease mutant of Pseudomonas putida

A spontaneous mutant of Pseudomonas putida (PRS 2017) has been isolated which is incapable of growth on benzoate, does not induce the enzymes of the catechol branch of the beta-ketoadipate pathway when grown in the presence of benzoate, cannot accumulate radioactively labeled benzoate, yet grows well with mandelate as sole source of carbon and energy. This strain apparently lacks a benzoate permease, which in the wild type shows a Km of about 0.1 mM for benzoate, is inducible, and is not under the control of the regulatory system which governs the induction of the enzymes of the catechol branch of the beta-ketoadapate pathway. The lesion in PRS2017 is apparently single site and maps near other genes governing benzoate dissimilation.