Crystal structure of Ruminococcus albus cellobiose 2‐epimerase: Structural insights into epimerization of unmodified sugar

摘要

RaCE andX‐raycrystallography(Viewinteraction).Enzymatic epimerization is an important modification for carbohydrates to acquire diverse functions attributable to their stereoisomers. Epimerases and racemases are isomerases that catalyze inversion of the configuration around an asymmetric center of substrates. Changing the stereochemistry of the hydroxyl substituent has biological significance in all branches of life. In humans, mutations found in the UDP‐glucose epimerase gene would be lethal 1. In plants, d‐ribulose‐5‐phosphate 3‐epimerase is a key enzyme in the Calvin cycle and the oxidative pentose phosphate pathway 2, 3. In pathogenic bacteria, epimerases are involved in the production of complex carbohydrate polymers used in their cell walls and envelopes to protect them from the host immune system 4..