Sucrose phosphorylase: a powerful transglucosylation catalyst for synthesis of alpha-D-glucosides as industrial fine chemicals

Sucrose phosphorylase is a bacterial transglucosidase that catalyzes conversion of sucrose and phosphate into alpha-D-glucose-1-phosphate and D-fructose. The enzyme utilizes a glycoside hydrolase-like double displacement mechanism that involves a catalytically competent P-glucosyl enzyme intermediate. In addition to reaction with phosphate, glucosylated sucrose phosphorylase can undergo hydrolysis to yield alpha-D-glucose or it can decompose via glucosyl transfer to a hydroxy group in suitable acceptor molecules, giving new alpha-D-glucosidic products. The glucosyl acceptor specificity of sucrose phosphorylase is reviewed, focusing on applications of the enzyme in glucoside synthesis. Polyhydroxylated compounds such as sugars and sugar alcohols are often glucosylated efficiently. Aryl alcohols and different carboxylic acids also serve as acceptors for enzymatic transglucosylation. The natural osmolyte 2-O-(alpha-D-glucopyranosyl)-sn-glycerol (GG) was prepared by regioselective glucosylation of glycerol from sucrose using the phosphorylase from Leuconostoc mesenteroides. An industrial process for production of GG as active ingredient of cosmetic formulations has been recently developed. General advantages of sucrose phosphorylase as a transglucosylation catalyst lie in the use of sucrose as a high-energy glucosyl donor and the usually weak hydrolase activity of the enzyme towards substrate and product.