Energetics of the Glycosyl Transfer Reactions of Sucrose Phosphorylase.

ABSTRACT: From its structure and mechanism, sucrose phosphorylase is a specialized glycoside hydrolase that uses phosphate ions instead of water as the nucleophile of the reaction. Unlike the hydrolysis reaction, the phosphate reaction is readily reversible and, here, this has enabled the study of temperature effects on kinetic parameters to map the energetic profile of the complete catalytic process via a covalent glycosyl enzyme intermediate. Enzyme glycosylation from sucrose and α-glucose 1-phosphate (Glc1P) is rate-limiting in the forward (k_cat = 84 s^-1) and reverse direction (k_cat = 22 s^-1) of reaction at 30 °C. Enzyme-substrate association is driven by entropy (TΔS_b ≥ +23 kJ/mol), likely arising from enzyme deso

SUBMITTER: Vyas A 

PROVIDER: S-EPMC10286314 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature