title: Adaptation of Alcaligenes eutrophus B9 and Pseudomonas sp. B13 to 2-Fluorobenzoate as Growth Substrate.
abstract: Alcaligenes eutrophus B9 and Pseudomonas sp. B13 could be adapted to 2-fluorobenzoate as the sole source of carbon and energy. The ability of the A. eutrophus B9 to use this new substrate is clearly based on the defective dihydrodihydroxybenzoate dehydrogenase. Nontoxic 6-fluoro-3,5-cyclohexadiene-1,2-diol-1-carboxylic acid is accumulated instead of 3-fluorocatechol. About 84% of the substrate is dioxygenated to catechol and utilized via the 3-oxoadipate pathway. During continuous adaptation of Pseudomonas sp. B13 regioselectivity of dioxygenation of 2-fluorobenzoate is drastically changed in favor of a 1,2-attack. Consequently, approximately 97% of the substrate is utilized via catechol. A three- to fourfold overproduction of key enzymes of the 3-oxoadipate pathway compensates for the slower turnover rates of the fluorinated substrates.
authors.affiliation: Institut für Mikrobiologie der Gesellschaft für Strahlen-und Umweltforschung, D-3400 Göttingen, West Germany.
authors.forename: K H
authors.initials: KH
authors.lastname: Engesser
authors.forename: E
authors.initials: E
authors.lastname: Schmidt
authors.forename: H J
authors.initials: HJ
authors.lastname: Knackmuss