Structural Basis of Polyketide Synthase O-Methylation.
ACS Chem Biol
; 13(12): 3221-3228, 2018 12 21.
Article
en En
| MEDLINE
| ID: mdl-30489068
ABSTRACT
Modular type I polyketide synthases (PKSs) produce some of the most chemically complex metabolites in nature through a series of multienzyme modules. Each module contains a variety of catalytic domains to selectively tailor the growing molecule. PKS O-methyltransferases ( O-MTs) are predicted to methylate ß-hydroxyl or ß-keto groups, but their activity and structure have not been reported. We determined the domain boundaries and characterized the catalytic activity and structure of the StiD and StiE O-MTs, which methylate opposite ß-hydroxyl stereocenters in the myxobacterial stigmatellin biosynthetic pathway. Substrate stereospecificity was demonstrated for the StiD O-MT. Key catalytic residues were identified in the crystal structures and investigated in StiE O-MT via site-directed mutagenesis and further validated with the cyanobacterial CurL O-MT from the curacin biosynthetic pathway. Initial structural and biochemical analysis of PKS O-MTs supplies a new chemoenzymatic tool, with the unique ability to selectively modify hydroxyl groups during polyketide biosynthesis.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Sintasas Poliquetidas
/
Policétidos
/
Metiltransferasas
Idioma:
En
Revista:
ACS Chem Biol
Año:
2018
Tipo del documento:
Article
País de afiliación:
Estados Unidos