title: Synthesis of amidrazones using an engineered papain nitrile hydratase.
abstract: To demonstrate the usefulness of an engineered papain nitrile hydratase as a biocatalyst, a peptide amidrazone was prepared by incubation of the nitrile MeOCO-Phe-Alanitrile with the Gln19Glu papain mutant in the presence of salicylic hydrazide as a nucleophile. The amidrazone results from nucleophilic attack by salicylic hydrazide at the imino carbon of the thioimidate adduct formed between the enzyme and the peptide nitrile substrate. Compared to wild-type enzyme, the engineered nitrile hydratase causes a better than 4000-fold increase in the rate of amidrazone formation and yields a product of much higher purity. The advantages over other nitrile-hydrolyzing enzymes and current limitations of the papain nitrile hydratase are discussed.
authors.affiliation: Biotechnology Research Institute, National Research Council of Canada, Montreal, Que.
authors.forename: E
authors.initials: E
authors.lastname: Dufour
authors.forename: W
authors.initials: W
authors.lastname: Tam
authors.forename: D K
authors.initials: DK
authors.lastname: Nägler
authors.forename: A C
authors.initials: AC
authors.lastname: Storer
authors.forename: R
authors.initials: R
authors.lastname: Ménard
mesh_terms: D002384:Catalysis; D018698:Glutamic Acid; D005973:Glutamine; D006835:Hydrazones / Q000138:chemical synthesis* / Q000737:chemistry; D006836:Hydro-Lyases / Q000235:genetics / Q000378:metabolism*; D006868:Hydrolysis; D016296:Mutagenesis; D010206:Papain / Q000235:genetics / Q000378:metabolism*; D010843:Pichia / Q000235:genetics; D015202:Protein Engineering; D011994:Recombinant Proteins; D012459:Salicylates / Q000737:chemistry
chemical_list: D006835:Hydrazones; D011994:Recombinant Proteins; D012459:Salicylates; D005973:Glutamine; D018698:Glutamic Acid; D010206:Papain; D006836:Hydro-Lyases; C048831:nitrile hydratase