FhuA–Grubbs–Hoveyda Biohybrid Catalyst Embedded in a Polymer Film Enables Catalysis in Neat Substrates

27/10/2020
  Daniel Sauer and Tayebeh Mirzaei Garakani Copyright: © Bio VI

Tayebeh Mirzaei Garakani#, Daniel F. Sauer#, M.A. Stephanie Mertens, Jaroslav Lazar, Julia Gehrmann, Marcus Arlt, Johannes Schiffels, Uwe Schnakenberg, Jun Okuda, Ulrich Schwaneberg*, ACS Catalysis, 2020, 19, 10946-10953

Embedment of an artificial metalloprotein into a synthetic polymer film enables biohybrid catalysis in neat substrates.

Expanding synthetic capabilities by combining principles of biocatalysis (e.g., control of selectivity) with metal-catalyzed reactions that do not have their counterpart in nature is of high synthetic value. This manuscript reports for the first time biohybrid catalysis in neat substrates and not aqueous solutions. Being able to perform biohybrid catalysis in the “organic-solvent realm” expands the repertoire of metal catalysts that could be utilized to construct biohybrid catalysts opening exciting new opportunities in chemical synthesis. The biohybrid catalyst presented here consists of a Grubbs-Hoveyda type olefin metathesis catalyst embedded in the FhuA-protein, which is embedded in a poly (N-methyl pyrrole) matrix that stabilizes the FhuA-ß-barrel structure. Thereby, ring-closing metathesis in two different neat substrates has been performed. The here presented system has its strength especially in neat, hydrophobic substrates, where the biohybrid film performed 24-fold better compared to its homogeneous analogue. This work may inspire the catalysis community to regard organic solvent as suitable reaction media for biohybrid catalysis and explore the broad reaction scope of metal catalysis in engineered protein backbones for selective and synthetically valuable reactions.

This research was funded by the Bundesministerium für Bildung und Forschung (BMBF) in the framework of the BMBF-project “Chiral Membranes” (Förderkennzeichen: 031A164 and 031B0559) and the research award project “Hyka-synBio” (Förderkennzeichen: 031B0297). The authors further acknowledge the Deutsche Forschungsgemeinschaft (DFG) throug the international research training group “Selectivity in Chemo- and Biocatalysis” (IRTG 1628, SeleCa) for financial support. We thank Umicore, Frankfurt (Dr. A. Doppiu), for a generous gift of ruthenium precursor.

  Knight fights against fire-breathing dragon. Copyright: © Bio VI

Figure: A biohybrid catalyst consisting of the b-barrel protein FhuA equipped with a Grubbs-Hoveyda type catalyst as active site (sword) is embedded into a poly(N-methylpyrrole) matrix (knight’s armor), enabling the protein to withstand harsh conditions like neat substrates (dragon flame).