ABSTRACT
Figure 3.2 Catalysis of phosphorylase.The second well-studied phosphorylase-type enzyme is sucrose phosphorylase, which catalyzes the reversible phosphorolysis of sucrose into Glc-1-P and fructose in the presence of inorganic phosphate (Fig. 3.3) [7,8]. Therefore, this enzyme has been used with Glc-1-P and fructose for the synthesis of sucrose. Sucrose phosphorylase is found in bacterial cells and is considered to be involved in the metabolism of extracellular sucrose. The phosphorolysis reaction proceeds via a ping-pong bi-bi mechanism and the enzyme transfers α-glucosides even in the absence of inorganic phosphate [9]. Taking into consideration the reaction mechanism, sucrose phosphorylase is an α-glucosyl transferase that also transfers glucose to phosphate [10-12]. This enzyme shows strict substrate specificity with only sucrose, Glc-1-P, and α-d-glucosyl fluoride as a glycosyl donor. However, broad acceptor specificity was found in different studies. Using this enzyme in a transglucosyl manner, several α-glucosides have been synthesized in one step from sucrose and various glycosyl acceptors.
