[A comparative study of the formation of 2-keto-D-gluconic acid by free and immobilized cells of Pseudomonas putida].

The effect of glucose, oxygen and 2-keto-D-gluconic acid (2KG) concentrations on the 2KG production by free and immobilized cells of Pseudomonas putida was studied. The effect of these factors was found to be similar in case of both free and immobilized cells, but the rate of the 2KG production by the free cells was a little higher as compared to the immobilized cells.

[Effect of the medium composition on the accumulation of 2-keto-D-gluconic acid in Pseudomonas putida cultures].

The effect of the composition of the culture medium and the age of the culture on the activities of the enzymes involved in accumulation of 2-ketogluconic acid by Pseudomonas putida was studied. The activities of glucose and gluconate dehydrogenases that are responsible for direct oxidation of glucose to 2-ketogluconic acid, were 2-3 times higher during the active growth of the culture than in the stationary phase. The activities of 2-ketogluconokinase and 2-keto-6-phosphogluconate reductase, enzymes converting 2-ketogluconic acid, increased 2-4-fold on the glucose exhausting.