Effect of oxyanions on the glucose isomerase catalysed equilibrium: 1. Complexes of d-glucose and d-fructose with germanate

The complexing parameters of d-glucose and d-fructose with germanate, derived from various forms of germanium dioxide, have been studied under the conditions pertaining to the d-glucose isomerase (d-xylose isomerase, d-xylose ketol-isomerase, EC 5.3.1.5) reaction. The interaction of germanate with d-glucose and d-fructose at various pH values has been investigated by means of optical rotation methods. The effects of temperature and concentration on the extent of complex formation are reported. The results are used to predict suitable conditions for the enhancement of d-fructose yield in the reaction of d-glucose with this enzyme.