KINETIC-MODEL OF DISACCHARIDE OXIDATION BY AGROBACTERIUM-TUMEFACIENS

Disaccharides were microbially transformed to their corresponding 3-ke to-derivatives by resting cells of Agrobacterium tumefaciens NCPPB 396 . The kinetics and yield of this highly specific oxidation depend on s everal factors. The oxygen concentration especially has a major influe nce on the production of 8-keto-derivatives and was investigated kinet ically with respect to low stationary oxygen concentrations in solutio n. Experiments showed unconventional results that conflicted with norm al Michaelis-Menten kinetics. Akinetic model was developed and the kin etic constants were calculated. The model and experimental data for su crose, maltose, isomaltulose (palatinose), and leucrose are in good ag reement with each other. Initial reaction rates with different sugars using constant oxygen concentrations resulted in a Michaelis-Menten ty pe function. The complete kinetics, including the effect of disacchari de and oxygen concentrations, are presented. (C) 1995 John Wiley & Son s, Inc.