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Enzymes have evolved to catalyse challenging chemical transformations with high efficiency and selectivity. Although a number of artificial systems have been developed to recapitulate the catalytic activity of natural enzymes, they are mostly limited to catalysing relatively simple reactions owing to their ability to mimic only the active metal centres of natural enzymes, without incorporating the proximal amino acids or cofactors. Here we report a metal–organic framework-based artificial enzyme (metal–organic–zyme, MOZ) by integrating active metal centres, proximal amino acids and other cofactors into a tunable metal–organic framework monolayer. We design two libraries of MOZs to perform photocatalytic CO2 reduction and water oxidation reactions. Through tuning the incorporated amino acids in the MOZs, we systematically optimize the activity and selectivity of these libraries. Combining these optimized MOZs into a single system realizes complete artificial photosynthesis in the reaction of (1 + n) CO2 + 2H2O → CH4 + nCO + (2 + n/2)O2.
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Light‐driven catalysis with engineered enzymes and biomimetic systems
Abstract Efforts to drive catalytic reactions with light, inspired by natural processes like photosynthesis, have a long history and have seen significant recent growth. Successfully engineering systems using biomolecular and bioinspired catalysts to carry out light‐driven chemical reactions capitalizes on advantages offered from the fields of biocatalysis and photocatalysis. In particular, driving reactions under mild conditions and in water, in which enzymes are operative, using sunlight as a renewable energy source yield environmentally friendly systems. Furthermore, using enzymes and bioinspired systems can take advantage of the high efficiency and specificity of biocatalysts. There are many challenges to overcome to fully capitalize on the potential of light‐driven biocatalysis. In this mini‐review, we discuss examples of enzymes and engineered biomolecular catalysts that are activated via electron transfer from a photosensitizer in a photocatalytic system. We place an emphasis on selected forefront chemical reactions of high interest, including CH oxidation, proton reduction, water oxidation, CO2reduction, and N2reduction.
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- Award ID(s):
- 1708256
- PAR ID:
- 10456810
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Biotechnology and Applied Biochemistry
- Volume:
- 67
- Issue:
- 4
- ISSN:
- 0885-4513
- Page Range / eLocation ID:
- p. 463-483
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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