May 4, 2024

Artificial Photosynthesis Breakthrough – Researchers Produce Hybrid Solid Catalysts

Scientists have actually utilized in-cell engineering to produce hybrid strong drivers for artificial photosynthesis using protein crystals. These catalysts, developed through genetically modified bacteria, are extremely active, long lasting, and eco-friendly, leading the way for an unique method in enzyme immobilization.
Researchers at Tokyo Tech have shown that in-cell engineering is an efficient approach for developing practical protein crystals with promising catalytic residential or commercial properties. By harnessing genetically transformed bacteria as a green synthesis platform, the scientists produced hybrid strong catalysts for synthetic photosynthesis. These drivers exhibit high activity, stability, and durability, highlighting the capacity of the proposed ingenious technique.
Protein crystals, like regular crystals, are well-ordered molecular structures with varied properties and a big potential for customization. They can put together naturally from materials found within cells, which not just significantly decreases the synthesis expenses but also lessens their environmental effect.
Although protein crystals are promising as drivers due to the fact that they can host different functional molecules, present techniques just enable the accessory of small particles and simple proteins. Therefore, it is imperative to discover ways to produce protein crystals bearing both natural enzymes and synthetic practical particles to tap their complete potential for enzyme immobilization.

Researchers at Tokyo Tech have demonstrated that in-cell engineering is an efficient method for producing practical protein crystals with appealing catalytic properties. By harnessing genetically modified bacteria as a green synthesis platform, the researchers produced hybrid solid catalysts for artificial photosynthesis. This gene caused the bacteria to produce FDH enzymes with H1 terminals, leading to the formation of hybrid H1-FDH@PhC crystals within the cells.
Through this ingenious procedure, the team managed to produce highly active, recyclable, and thermally steady EY·H1-FDH@PhC drivers that can transform carbon dioxide (CO2) into formate (HCOO −) upon exposure to light, simulating photosynthesis. “The conversion efficiency of the proposed hybrid crystal was an order of magnitude greater than that of formerly reported substances for enzymatic artificial photosynthesis based on FDH,” highlights Prof. Ueno.

Versus this backdrop, a team of researchers from Tokyo Institute of Technology (Tokyo Tech) led by Professor Takafumi Ueno has actually developed an innovative method to produce hybrid solid drivers based on protein crystals. As discussed in their paper released in Nano Letters on 12 July 2023, their method integrates in-cell engineering and a simple in vitro process to produce catalysts for artificial photosynthesis.
Graphic explaining the research. Credit: Professor Takafumi Ueno, Tokyo Institute of Technology
The foundation of the hybrid catalyst is a protein monomer originated from a virus that infects the Bombyx mori silkworm. The scientists introduced the gene that codes for this protein into Escherichia coli bacteria, where the produced monomers formed trimers that, in turn, spontaneously put together into stable polyhedra crystals (PhCs) by binding to each other through their N-terminal α-helix (H1). In addition, the scientists presented a modified version of the formate dehydrogenase (FDH) gene from a types of yeast into the E. coli genome. This gene triggered the bacteria to produce FDH enzymes with H1 terminals, resulting in the development of hybrid H1-FDH@PhC crystals within the cells.
The team extracted the hybrid crystals out of the E. coli germs through sonication and gradient centrifugation and soaked them in a solution containing a synthetic photosensitizer called eosin Y (EY). As an outcome, the protein monomers, which had actually been genetically modified such that their main channel might host an eosin Y particle, assisted in the stable binding of EY to the hybrid crystal in large quantities.
Through this innovative process, the group managed to produce extremely active, recyclable, and thermally steady EY·H1-FDH@PhC drivers that can convert carbon dioxide (CO2) into formate (HCOO −) upon exposure to light, mimicking photosynthesis. “The conversion effectiveness of the proposed hybrid crystal was an order of magnitude greater than that of previously reported compounds for enzymatic synthetic photosynthesis based on FDH,” highlights Prof. Ueno.
Overall, this study showcases the potential of bioengineering in helping with the synthesis of complicated practical materials. “The combination of in vivo and in vitro methods for the encapsulation of protein crystals will likely supply a ecologically friendly and effective strategy for research in the locations of nanomaterials and synthetic photosynthesis,” concludes Prof. Ueno.
And we sure hope that these efforts will lead us to a greener future!
Recommendation: “In-Cell Engineering of Protein Crystals into Hybrid Solid Catalysts for Artificial Photosynthesis” by Tiezheng Pan, Basudev Maity, Satoshi Abe, Taiki Morita and Takafumi Ueno, 12 July 2023, Nano Letters.DOI: 10.1021/ acs.nanolett.3 c02355.