title: Enzymatic fluorination in Streptomyces cattleya takes place with an inversion of configuration consistent with an SN2 reaction mechanism.
abstract: The stereochemical course of the recently isolated fluorination enzyme from Streptomyces cattleya has been evaluated. The enzyme mediates a reaction between the fluoride ion and S- adenosyl-L-methionine (SAM) to generate 5'-fluoro-5'-deoxyadenosine (5'-FDA). Preparation of (5'R)-[5-(2)H(1)]-ATP generated (5'R)-[5-(2)H(1)]-5'-FDA in a coupled enzyme assay involving SAM synthase and the fluorinase. The stereochemical analysis of the product relied on (2)H NMR analysis in a chiral liquid-crystalline medium. It is concluded that the enzyme catalyses the fluorination with an inversion of configuration consistent with an S(N)2 reaction mechanism.
authors.affiliation: School of Chemistry and Centre for Biomolecular Sciences, University of St Andrews, St Andrews, Fife, KY16 9ST, UK.
authors.forename: Cosimo D
authors.initials: CD
authors.lastname: Cadicamo
authors.forename: Jacques
authors.initials: J
authors.lastname: Courtieu
authors.forename: Hai
authors.initials: H
authors.lastname: Deng
authors.forename: Abdelkrim
authors.initials: A
authors.lastname: Meddour
authors.forename: David
authors.initials: D
authors.lastname: O'Hagan
mesh_terms: D002384:Catalysis; D005459:Fluorides / Q000737:chemistry*; D008716:Methionine Adenosyltransferase / Q000737:chemistry*; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D012436:S-Adenosylmethionine / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism; D013302:Streptomyces / Q000201:enzymology* / Q000378:metabolism
chemical_list: D012436:S-Adenosylmethionine; D008716:Methionine Adenosyltransferase; D005459:Fluorides