RESPIRATORY ACTIVITY OF CELL-FREE EXTRACTS FROM AZOTOBACTER

Abstract

Cell-free extracts of A. vinelandii having the ability to oxidize acetate, pyruvate, and the acids of the citric acid cycle were prepared by wet crushing with a bacterial mill, grinding with alumina, and irradiation by ultrasonic waves. The oxidation of acids of the citric acid cycle proceeded without any demonstrable lag period although the parent cell suspensions required varying lag periods or were inactive on these substrates. The clear cut demonstration of the "sparking" effect in the oxidation of acetate and pyruvate by these extracts and the stimulation found with Coenzyme A suggest that the primary pathway of oxidation of A. vinelandii is via the tricarboxylic acid cycle.