Structural basis of the amidase ClbL central to the biosynthesis of the genotoxin colibactin.
Acta Crystallogr D Struct Biol
; 79(Pt 9): 830-836, 2023 Sep 01.
Article
en En
| MEDLINE
| ID: mdl-37561403
ABSTRACT
Colibactin is a genotoxic natural product produced by select commensal bacteria in the human gut microbiota. The compound is a bis-electrophile that is predicted to form interstrand DNA cross-links in target cells, leading to double-strand DNA breaks. The biosynthesis of colibactin is carried out by a mixed NRPS-PKS assembly line with several noncanonical features. An amidase, ClbL, plays a key role in the pathway, catalyzing the final step in the formation of the pseudodimeric scaffold. ClbL couples α-aminoketone and ß-ketothioester intermediates attached to separate carrier domains on the NRPS-PKS assembly. Here, the 1.9â
Å resolution structure of ClbL is reported, providing a structural basis for this key step in the colibactin biosynthetic pathway. The structure reveals an open hydrophobic active site surrounded by flexible loops, and comparison with homologous amidases supports its unusual function and predicts macromolecular interactions with pathway carrier-protein substrates. Modeling protein-protein interactions supports a predicted molecular basis for enzyme-carrier domain interactions. Overall, the work provides structural insight into this unique enzyme that is central to the biosynthesis of colibactin.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Escherichia coli
/
Mutágenos
Tipo de estudio:
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
Acta Crystallogr D Struct Biol
Año:
2023
Tipo del documento:
Article
País de afiliación:
Estados Unidos