A Single Point Mutation Converts GH84 O-GlcNAc Hydrolases into Phosphorylases: Experimental and Theoretical Evidence.
J Am Chem Soc
; 142(5): 2120-2124, 2020 02 05.
Article
en En
| MEDLINE
| ID: mdl-31917561
ABSTRACT
Glycoside hydrolases and phosphorylases are two major classes of enzymes responsible for the cleavage of glycosidic bonds. Here we show that two GH84 O-GlcNAcase enzymes can be converted to efficient phosphorylases by a single point mutation. Noteworthy, the mutated enzymes are over 10-fold more active than naturally occurring glucosaminide phosphorylases. We rationalize this novel transformation using molecular dynamics and QM/MM metadynamics methods, showing that the mutation changes the electrostatic potential at the active site and reduces the energy barrier for phosphorolysis by 10 kcal·mol-1. In addition, the simulations unambiguously reveal the nature of the intermediate as a glucose oxazolinium ion, clarifying the debate on the nature of such a reaction intermediate in glycoside hydrolases operating via substrate-assisted catalysis.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Mutación Puntual
/
Fosforilasas
/
Glicósido Hidrolasas
Idioma:
En
Revista:
J Am Chem Soc
Año:
2020
Tipo del documento:
Article
País de afiliación:
Dinamarca