title: Artificial metalloenzymes: (strept)avidin as host for enantioselective hydrogenation by achiral biotinylated rhodium-diphosphine complexes.
abstract: We report on the generation of artificial metalloenzymes based on the noncovalent incorporation of biotinylated rhodium-diphosphine complexes in (strept)avidin as host proteins. A chemogenetic optimization procedure allows one to optimize the enantioselectivity for the reduction of acetamidoacrylic acid (up to 96% ee (R) in streptavidin S112G and up to 80% ee (S) in WT avidin). The association constant between a prototypical cationic biotinylated rhodium-diphosphine catalyst precursor and the host proteins was determined at neutral pH: log K(a) = 7.7 for avidin (pI = 10.4) and log K(a) = 7.1 for streptavidin (pI = 6.4). It is shown that the optimal operating conditions for the enantioselective reduction are 5 bar at 30 degrees C with a 1% catalyst loading.
authors.affiliation: Institute of Chemistry, University of Neuchâtel, Avenue Bellevaux 51, CP2, CH-2007 Neuchâtel, Switzerland.
authors.forename: Myriem
authors.initials: M
authors.lastname: Skander
authors.forename: Nicolas
authors.initials: N
authors.lastname: Humbert
authors.forename: Jérôme
authors.initials: J
authors.lastname: Collot
authors.forename: Julieta
authors.initials: J
authors.lastname: Gradinaru
authors.forename: Gérard
authors.initials: G
authors.lastname: Klein
authors.forename: Andreas
authors.initials: A
authors.lastname: Loosli
authors.forename: Jérôme
authors.initials: J
authors.lastname: Sauser
authors.forename: Andrea
authors.initials: A
authors.lastname: Zocchi
authors.forename: François
authors.initials: F
authors.lastname: Gilardoni
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Ward
mesh_terms: D000179:Acrylates / Q000737:chemistry; D001360:Avidin / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism; D001710:Biotin / Q000031:analogs & derivatives / Q000737:chemistry; D002384:Catalysis; D004798:Enzymes / Q000138:chemical synthesis / Q000737:chemistry*; D006865:Hydrogenation; D007700:Kinetics; D008667:Metalloproteins / Q000138:chemical synthesis / Q000737:chemistry*; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D010720:Phosphines / Q000737:chemistry*; D012238:Rhodium / Q000737:chemistry*; D013237:Stereoisomerism; D019809:Streptavidin / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics
chemical_list: D000179:Acrylates; D004798:Enzymes; D008667:Metalloproteins; D010720:Phosphines; D001360:Avidin; D001710:Biotin; D019809:Streptavidin; D012238:Rhodium