Studies on Oxidative Fermentation

Part XXI. Catabolism of 5-Ketogluconate by Gluconobacter liquefaciens. II

Abstract

Oxidation pathways of 5-ketogluconic acid by resting cells of Gluconobacter liquefaciens were further investigated. Arsenite inhibited the oxidation of this compound. The amount of carbonyl compounds in the oxidation products of 5-ketogluconic acid was increased by addition of 10^-3M arsenite. Pyruvic and α-ketoglutaric acids were identified among these carbonyl compounds. Members of the tricarboxylic acid cycle were oxidized actively by resting cells or cell-free extracts of this organism. These results suggested the presence of the tricarboxylic acid cycle in the terminal oxidation of 5-ketogluconic acid by this organism.