Bridging the Chemical and Biological Catalysis Gap: Challenges and Outlooks for Producing Sustainable Chemicals

TLDR

Recent advances in metabolic engineering enable the biocatalytic production of diverse molecules, and the high selectivity of biocatalysis can generate platform compounds that, when upgraded by continuous chemical catalysis, may replace petroleum products. We review recent work combining chemical and biological catalysis and identify challenges to bridge the gap between them from a heterogeneous catalysis perspective. We propose that studies must evaluate how bioprocessing impurities affect catalyst performance, develop liquid‑phase heterogeneous catalysts tolerant to biogenic contaminants, and design new catalysts with tailored active sites for selective conversion of functional groups in biologically derived platform molecules.

Abstract

Recent advances in metabolic engineering have allowed for the production of a wide array of molecules via biocatalytic routes. The high selectivity of biocatalysis to remove functionality from biomass can be used to produce platform molecules that are suitable for subsequent upgrading over heterogeneous catalysts. Accordingly, the more robust continuous processing allowed by chemical catalysis could be leveraged to upgrade biologically derived platform molecules to produce direct or functional replacements for petroleum products. Herein, we highlight recent results that utilize a combination of chemical and biological catalysis, and using the perspective of heterogeneous chemical catalysis, we identify challenges that need to be addressed to bridge the gap between the two catalytic approaches. Specifically, studies are required to address the effects on catalyst performance of impurities that originate during bioprocessing. In addition, new generations of heterogeneous catalysts are required for stable operation under liquid phase reaction conditions in the presence of biogenic impurities. Finally, the design and syntheses of new catalysts are required to tailor the active sites and the environment around these sites to achieve selective conversion of the functional groups present in biologically derived platform molecules.