Inducible Uptake System for β-Carboxy- cis, cis -muconate in a Permeability Mutant of Pseudomonas putida

Open Access
Publisher Website
Google Scholar
Abstract
A procedure for the large-scale enzymatic synthesis of β-carboxymuconate is described. When used as a growth substrate, β-carboxymuconate selected for mutant strains of Pseudomonas putida that were permeable to polycarboxylic acid intermediates of the β-ketoadipate pathway. One mutant organism, strain PRS2110, was investigated in detail. It differed from the parental strain in that it possessed a β-carboxymuconate uptake system that was formed when the compound was supplied exogenously to the cells. The uptake system was not induced by β-carboxymuconate supplied endogenously during growth with p -hydroxybenzoate. These observations suggested that β-carboxymuconate was contained within a physical compartment of enzymes during growth with p -hydroxybenzoate. Support for this hypothesis came from the demonstration that enzymes of the β-ketoadipate pathway were held together by weak chemical interactions during the chromatography of crude extracts of benzoategrown P. putida on diethylaminoethyl-cellulose columns.