Transglycosylic reactions of nucleotides of deoxy sugars. Biosynthesis of deoxy analogues of alpha,alpha'-trehalose.

The biosynthesis of alpha,alpha'-trehalose was investigated in a reaction catalyzed with yeast UDP-Glc :glucose-6-phosphate 1-glucosyl transferase. It was revealed that the hydroxyls at positions C-2, C-3, C-4 and C-6 are not essential for preserving its substrate properties in this reaction. The affinity of the enzyme and the rate of hexose incorporation into trehalose decreases in following sequence: UDP-glucose, UDP-2-deoxy-D-glucose, UDP-6-deoxy-d-glucose, UDP-4-deoxy-D-glucose and UDP-3-deoxy-D-glucose.