Trehalose Phosphate Synthesis in Streptomyces hygroscopicus: Purification of Guanosine Diphosphate d -Glucose: d -Glucose-6-Phosphate 1-Glucosyl-Transferase

Abstract

Guanosine diphosphate d -glucose: d -glucose-6-phosphate 1-glucosyl-transferase was purified approximately 100-fold from extracts of Streptomyces hygroscopicus . The purified enzyme catalyzed the transfer of glucose from guanosine diphosphate- d -glucose to glucose-6-phosphate to form trehalose phosphate and guanosine diphosphate. The enzyme was specific for these two substrates and was stimulated by the addition of magnesium ions. The product was characterized as α-α-trehalose-6-phosphate by its physical and chemical properties. The enzyme was present in a large number of Streptomyces species, suggesting that this group of organisms synthesized trehalose phosphate in a unique manner. This enzyme was not detected in fungi, since these organisms utilized uridine diphosphate- d -glucose as the glucosyl donor.