Structural and Spectroscopic Characterization of a Product Schiff Base Intermediate in the Reaction of the Quinoprotein Glycine Oxidase, GoxA.
Biochemistry
; 58(6): 706-713, 2019 02 12.
Article
en En
| MEDLINE
| ID: mdl-30605596
ABSTRACT
The LodA-like proteins make up a recently identified family of enzymes that rely on a cysteine tryptophylquinone cofactor for catalysis. They differ from other tryptophylquinone enzymes in that they are oxidases rather than dehydrogenases. GoxA is a member of this family that catalyzes the oxidative deamination of glycine. Our previous work with GoxA from Pseudoalteromonas luteoviolacea demonstrated that this protein forms a stable intermediate upon anaerobic incubation with glycine. The spectroscopic properties of this species were unique among those identified for tryptophylquinone enzymes characterized to date. Here we use X-ray crystallography and resonance Raman spectroscopy to identify the GoxA catalytic intermediate as a product Schiff base. Structural work additionally highlights features of the active site pocket that confer substrate specificity, intermediate stabilization, and catalytic activity. The unusual properties of GoxA are discussed within the context of the other tryptophylquinone enzymes.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Bases de Schiff
/
Aminoácido Oxidorreductasas
/
Glicina
Idioma:
En
Revista:
Biochemistry
Año:
2019
Tipo del documento:
Article
País de afiliación:
Estados Unidos