Among the numerous well-characterized families of glycosidases, family 4 appears to be the anomaly, requiring both catalytic NAD+ and a divalent metal for activity. The unusual cofactor requirement prompted the proposal of a mechanism involving key NAD+-mediated redox steps as well as elimination of the glycosidic oxygen. Primary kinetic isotope effects for the 2- and 3-deutero substrate analogues, isotopic exchange with solvent, and structural analysis of a 6-phospho-β-glucosidase, BglT (E.C. 188.8.131.52), provided evidence in support of the proposed mechanism, which has striking resemblances to that of the sugar dehydratases. Furthermore, analysis of the stereochemical outcome indicated that family 4 enzymes are retaining glycosidases.
|Original language||English (US)|
|Number of pages||2|
|Journal||Journal of the American Chemical Society|
|State||Published - Jul 14 2004|
ASJC Scopus subject areas
- Colloid and Surface Chemistry