Discovery of a Promiscuous Non-Heme Iron Halogenase in Ambiguine Alkaloid Biogenesis: Implication for an Evolvable Enzyme Family for Late-Stage Halogenation of Aliphatic Carbons in Small Molecules.
Angew Chem Int Ed Engl
; 55(19): 5780-4, 2016 05 04.
Article
in En
| MEDLINE
| ID: mdl-27027281
ABSTRACT
The elucidation of enigmatic enzymatic chlorination timing in ambiguine indole alkaloid biogenesis led to the discovery and characterization of AmbO5 protein as a promiscuous non-heme iron aliphatic halogenase. AmbO5 was shown capable of selectively modifying seven structurally distinct ambiguine, fischerindole and hapalindole alkaloids with chlorine via late-stage aliphatic C-H group functionalization. Cross-comparison of AmbO5 with a previously characterized aliphatic halogenase homolog WelO5 that has a restricted substrate scope led to the identification of a C-terminal sequence motif important for substrate tolerance and specificity. Mutagenesis of 18 residues of WelO5 within the identified sequence motif led to a functional mutant with an expanded substrate scope identical to AmbO5, but an altered substrate specificity from the wild-type enzymes. These observations collectively provide evidence on the evolvable nature of AmbO5/WelO5 enzyme duo in the context of hapalindole-type alkaloid biogenesis and implicate their promise for the future development of designer biocatalysis for the selective late-stage modification of unactivated aliphatic carbon centers in small molecules with halogens.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Oxidoreductases
/
Bacterial Proteins
/
Alkaloids
Language:
En
Journal:
Angew Chem Int Ed Engl
Year:
2016
Document type:
Article
Affiliation country:
United States
Country of publication:
ALEMANHA
/
ALEMANIA
/
DE
/
DEUSTCHLAND
/
GERMANY