Enzymatic characterization of sucrose phosphorylase from Bifidobacterium dentium: The initial enzyme in the cascade reaction

Abstract

Sucrose phosphorylase (SPase) catalyzes the conversion of sucrose to ⍺-Glucose 1-phosphate (G-1-P) and fructose. G-1-P functions as a glycosyl donor and is an initial substrate for biosynthesis cascades. This study characterized the enzymatic properties of a novel SPase from Bifidobacterium dentium (BdSP) and explored its potential as an initial enzyme in cascade reactions. BdSP displayed 91–93% homology with the SPase from Bifidobacterium species. Recombinant BdSP was characterized as a dimer with optimal temperatures of 55 °C and 60 °C and pH of 7.0 and 5.0 for the phosphorolysis and synthesis reactions, respectively. The melting temperature of BdSP was 68.91 °C, and its half-life was 235.1 min at 65 °C. Kinetic studies demonstrated that BdSP can produce G-1-P from sucrose more efficiently than other SPases, with a production rate of 68% at 55 °C for 2 h. Furthermore, the cascade reaction of BdSP and cellobiose phosphorylase from Clostridium thermocellum YM4 (CtCBP) reached an effective production of cellobiose (80.4%) at 55 °C for 18 h.