Université de Neuchâtel

Artificial Metalloenzymes: (Strept)avidin as Host for Enantioselective Hydrogenation by Achiral Biotinylated Rhodium−Diphosphine Complexes

Skander, Myriem ; Humbert, Nicolas ; Collot, Jérôme ; Gradinaru, Julieta ; Klein, Gérard ; Loosli, Andreas ; Sauser, Jérôme ; Zocchi, Andrea ; Gilardoni, François ; Ward, Thomas R.

In: Journal of the American Chemical Society (JACS), 2004, vol. 126, no. 44, p. 14411–14418

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)....

Université de Neuchâtel

Artificial Metalloenzymes for Enantioselective Catalysis Based on Biotin−Avidin

Collot, Jérôme ; Gradinaru, Julieta ; Humbert, Nicolas ; Skander, Myriem ; Zocchi, Andrea ; Ward, Thomas R.

In: Journal of the American Chemical Society (JACS), 2003, vol. 125, no. 30, p. 9030-9031

Incorporation of biotinylated racemic three-legged d6-piano stool complexes in streptavidin yields enantioselective transfer hydrogenation artificial metalloenzymes for the reduction of ketones. Having identified the most promising organometallic catalyst precursors in the presence of wild-type streptavidin, fine-tuning of the selectivity is achieved by saturation mutagenesis at...

Université de Neuchâtel

Second Generation Artificial Hydrogenases Based on the Biotin-Avidin Technology: Improving Activity, Stability and Selectivity by Introduction of Enantiopure Amino Acid Spacers

Rusbandi, Untung E. ; Lo, Cheikh ; Skander, Myriem ; Ivanova, Anita ; Creus, Marc ; Humbert, Nicolas ; Ward, Thomas R.

In: Advanced Synthesis & Catalysis, 2007, vol. 349, no. 11-12, p. 1923-1930

We report on our efforts to create efficient artificial metalloenzymes for the enantioselective hydrogenation of N-protected dehydroamino acids using either avidin or streptavidin as host proteins. Introduction of chiral amino acid spacers - phenylalanine or proline - between the biotin anchor and the flexible aminodiphosphine moiety 1, combined with saturation mutagenesis at...

Université de Neuchâtel

Second-generation artificial hydrogenases based on the biotin–avidin technology: Improving selectivity and organic solvent tolerance by introduction of an (R)-proline spacer

Rusbandi, Untung E. ; Skander, Myriem ; Ivanova, Anita ; Malan, Christophe ; Ward, Thomas R.

In: Comptes Rendus Chimie, 2007, vol. 10, no. 8, p. 678-683

We report on our efforts to create efficient artificial metalloenzymes for the enantioselective hydrogenation of N-protected dehydroamino acids using streptavidin as host protein. Introduction of an (R)-proline spacer between the biotin anchor and the diphosphine moiety affords a versatile ligand Biot-(R)-Pro-1 which displays good (S)-selectivities in the...

Université de Neuchâtel

Chemical optimization of artificial metalloenzymes based on the biotin-avidin technology: (S)-selective and solvent-tolerant hydrogenation catalysts via the introduction of chiral amino acid spacers

Skander, Myriem ; Malan, Christophe ; Ivanova, Anita ; Ward, Thomas R.

In: Chemical Communications (ChemComm), 2005, vol. 38, p. 4815-4817

Incorporation of biotinylated-[rhodium(diphosphine)]+ complexes, with enantiopure amino acid spacers, in streptavidin affords solvent-tolerant and selective artificial metalloenzymes: up to 91% ee (S) in the hydrogenation of N-protected dehydroamino acids.

Université de Neuchâtel

Artificial metalloenzymes for enantioselective catalysis : the phenomenon of protein accelerated catalysis

Collot, Jérôme ; Humbert, Nicolas ; Skander, Myriem ; Klein, Gérard ; Ward, Thomas R.

In: Journal of Organometallic Chemistry, 2005, vol. 689, p. 4868-4871

We report on the phenomenon of protein-accelerated catalysis in the field of artificial metalloenzymes based on the non-covalent incorporation of biotinylated rhodium–diphosphine complexes in (strept)avidin as host proteins. By incrementally varying the [Rh(COD)(Biot-1)]+ vs. (strept)avidin ratio, we show that the enantiomeric excess of the produced acetamidoalanine decreases slowly....

Université de Neuchâtel

Métalloenzymes artificielles : Nouvelle génération de catalyseurs efficaces pour l’hydrogénation énantiosélective

Skander, Myriem ; Ward, Thomas (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2005 ; 1832.

La catalyse chimique en phase homogène ainsi que la catalyse enzymatique sont deux méthodes complémentaires pour la préparation de composés énantiomériquement purs. Grâce à l’incorporation d’un complexe de rhodium – aminodiphosphine biotinylé dans la (strept)avidine, il est possible d’obtenir un catalyseur hybride pour l’hydrogénation énantiosélective. La synthèse de...