title: Protein-engineering of an amine transaminase for the stereoselective synthesis of a pharmaceutically relevant bicyclic amine.
abstract: Application of amine transaminases (ATAs) for stereoselective amination of prochiral ketones represents an environmentally benign and economically attractive alternative to transition metal catalyzed asymmetric synthesis. However, the restrictive substrate scope has limited the conversion typically to non-sterically demanding scaffolds. Recently, we reported on the identification and design of fold class I ATAs that effect a highly selective asymmetric synthesis of a set of chiral aromatic bulky amines from the corresponding ketone precursors in high yield. However, for the specific amine synthetic approach extension targeted here, the selective formation of an exo- vs. endo-isomer, these biocatalysts required additional refinement. The chosen substrate (exo-3-amino-8-aza-bicyclo[3.2.1]oct-8-yl-phenyl-methanone), apart from its pharmacological relevance, is a demanding target for ATAs as the bridged bicyclic ring provides substantial steric challenges. Protein engineering combining rational design and directed evolution enabled the identification of an ATA variant which catalyzes the specific synthesis of the target exo-amine with >99.5% selectivity.
authors.affiliation: Dept of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, D-17489 Greifswald, Germany. uwe.bornscheuer@uni-greifswald.de.
authors.forename: Martin S
authors.initials: MS
authors.lastname: Weiß
authors.affiliation: Dept of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, D-17489 Greifswald, Germany. uwe.bornscheuer@uni-greifswald.de and Group of Biotechnology, Dept of Biochemistry, University of Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel, Germany.
authors.forename: Ioannis V
authors.initials: IV
authors.lastname: Pavlidis
authors.affiliation: Process Research and Development, Biocatalysis, F. Hoffmann-La Roche Ltd., Grenzacher Str.124, 4070 Basel, Switzerland. hans.iding@roche.com.
authors.forename: Paul
authors.initials: P
authors.lastname: Spurr
authors.affiliation: Process Research and Development, Biocatalysis, F. Hoffmann-La Roche Ltd., Grenzacher Str.124, 4070 Basel, Switzerland. hans.iding@roche.com.
authors.forename: Steven P
authors.initials: SP
authors.lastname: Hanlon
authors.affiliation: Process Research and Development, Biocatalysis, F. Hoffmann-La Roche Ltd., Grenzacher Str.124, 4070 Basel, Switzerland. hans.iding@roche.com.
authors.forename: Beat
authors.initials: B
authors.lastname: Wirz
authors.affiliation: Process Research and Development, Biocatalysis, F. Hoffmann-La Roche Ltd., Grenzacher Str.124, 4070 Basel, Switzerland. hans.iding@roche.com.
authors.forename: Hans
authors.initials: H
authors.lastname: Iding
authors.affiliation: Dept of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, D-17489 Greifswald, Germany. uwe.bornscheuer@uni-greifswald.de.
authors.forename: Uwe T
authors.initials: UT
authors.lastname: Bornscheuer
mesh_terms: D000588:Amines / Q000138:chemical synthesis* / Q000737:chemistry*; D055162:Biocatalysis; D020134:Catalytic Domain; D060326:Chemistry Techniques, Synthetic; D007659:Ketones / Q000737:chemistry; D008958:Models, Molecular; D015202:Protein Engineering; D041902:Rhodobacteraceae / Q000201:enzymology; D013237:Stereoisomerism; D013379:Substrate Specificity; D000637:Transaminases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
chemical_list: D000588:Amines; D007659:Ketones; D000637:Transaminases