Artificial photosynthesis holds promise in producing solar fuels and chemicals. Although encouraging achievements have been made in the development of catalysts for reaction/ process modules in artificial photosynthesis, constructing a highly compatible complex reaction system remains a distant prospect. Herein, an artificial thylakoid is proposed and constructed by decorating the inner wall of protamine−titania (PTi) microcapsules with cadmium sulfide quantum dots (CdS QDs) for the photobiocoupled reduction of carbon dioxide (CO 2 ) via a single enzyme (formate dehydrogenase) and multiple enzymes (formate/formaldehyde/alcohol dehydrogenases). The size-selective capsule wall compartmentalizes photocatalytic oxidation and biocatalytic reduction, creating well-directed reaction sequences and protecting enzymes from deactivation. The favorable electronic coupling and band structure between CdS and PTi separate holes and electrons to afford an NADH regeneration rate of 4226 ± 121 μmol g −1 h −1 and optimized yield of 93.03 ± 3.84%. The photobiocoupled system achieves formate and methanol outputs of 1500 and 99 μM h −1 with a single enzyme and multiple enzymes, respectively. Our study may exploit a method for the construction of complex artificial catalytic systems with multiple reactions.

Solar energy conversion by photocatalysis holds promise in energy supply, but its efficiency is hindered by the mismatch in charge generation, transfer, and utilization. In natural photosynthesis, photosystem I (PSI) exhibits an intrinsic quantum efficiency of nearly 100% in solar energy conversion. The elaborate synergy of electron transfer and electron utilization guarantees the conversion of unstable excited electrons to stable electrons in reduced nicotinamide adenine dinucleotide phosphate (NADPH). To demonstrate this in vitro, we report a design of core−shell metal−organic frameworks (MOFs) as an "electron buffer tank" to coordinate electron transfer and electron utilization in photocatalysis. The electrons are generated via the irradiation on photosensitizers (2-aminoterephthalic acid, NH 2 -BDC) in the core and then transferred to Zr 6 O 8 clusters on the shell through the light-induced ligand-to-metal charge transfer mechanism. Neighboring reaction centers, [Cp*Rh(bpydc)H 2 O] 2+ , on the MOFs behave as the electron buffer tank and store these electrons in the form of hydrides for subsequent regeneration of reduced nicotinamide adenine dinucleotide (NADH). The electron lifetime is prolonged from nanoseconds to seconds, leading to 2.27-fold enhancement of electron availability and 2.08-fold enhancement of activity compared to the homogeneous reaction counterpart. The coupling of NADH regeneration and enzyme catalysis further enables the asymmetric reduction of carbonyl to chiral amine. The electron buffer tank concept may offer a generic strategy to coordinate mass transfer and chemical reaction in a broad range of catalytic processes.

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In-depth understanding and rational manipulation of the electron transfer process and molecule diffusion process are critical to promote the overall photocatalytic efficiency. In our study, core@shell photocatalysts that embody graphitic carbon nitride (GCN) core and amorphous titania (a-TiO2) nanoshell are prepared to elucidate and coordinate the electron transfer and molecule diffusion for the regeneration of nicotinamide adenine dinucleotide (NADH) with [Cp*Rh­(bpy)­H2O]2+ as the redox mediator. The GCN core absorbs visible light to generate electron–hole pairs, whereas the a-TiO2 nanoshell facilitates the transfer of photogenerated electrons from GCN to the a-TiO2 surface for NADH regeneration, which also enables the diffusion of electron donor molecules (triethanolamine, TEOA) from the a-TiO2 surface to GCN for consuming the holes left on GCN. The transfer of photogenerated electrons and the diffusion of electron donor molecules are coordinated by finely tuning the thickness of the a-TiO2 nanoshell. Under the optimized nanoshell thickness of ∼2.1 nm, the GCN@a-TiO2 photocatalyst exhibits the highest NADH regeneration yield of 82.1% after a 10 min reaction under LED light (405 nm), over 200% higher than that of the GCN photocatalyst. Combined with the highly controllable and mild features of the bioinspired mineralization method, our study may offer a facile and generic strategy to design high performance photocatalysts through rational coordination of different substances/species transport processes.

Thermodynamic analysis of tri-reforming reactions to produce synthesis gas has been conducted by total Gibbs energy minimization to understand the effects of process variables, such as temperature (200−1000 °C), pressure (1−20 atm), and inlet O 2 /CH 4 (0−1.0), H 2 O/CH 4 (0−3.0), and CO 2 /CH 4 (0−3.0) mole ratios on the product distribution. The results reveal that high temperature and low pressure are favorable to achieve high H 2 production and CO 2 conversion. In addition, excessive additions of H 2 O, O 2 , and CO 2 bring about lower H 2 yield and CO 2 conversion, while low concentrations of H 2 O, O 2 , and CO 2 result in more intense carbon formation. To attain the maximum H 2 yield and high CO 2 conversion coupled with a desired synthesis gas (H 2 /CO) ratio for the downstream methanol production and effective elimination of carbon formation, the corresponding optimum feed ratio in tri-reforming process is identified to be CH 4 /CO 2 /H 2 O/O 2 = 1:0.291:0.576:0.088.

Photoenzymatic coupled catalysis, integrating semiconductor photocatalysis and enzymatic catalysis, exhibits great potential for light-driven synthesis. To make photocatalyst and enzyme at play concertedly, nicotinamide-based cofactors have been widely used as electron carrier. However, these cofactors are easily oxidized into enzymatically inactive form by photo-generated holes. Herein, oxidation mechanism of NADH, one typical nicotinamide-based cofactor, by photo-generated holes was reported. With CdS, g-C3N4 and BiVO4 as hole generators, NADH is oxidized into NAD + or fragmented into ADP-ribose derivatives through multi-step electron transfer. Importantly, fragmentation reaction is inhibited with dopamine and neutral red to coordinate electron transfer between NADH and photo-generated holes.

Most plant fungal pathogens that cause worldwide crop losses are understudied due to various technical challenges. With the increasing availability of sequenced whole genomes of these non-model fungi, effective genetic analysis methods are highly desirable. Here we describe a newly developed pipeline, which combines forward genetic screening with high-throughput next-generation sequencing to enable quick gene discovery. We applied this pipeline in the notorious soilborne phytopathogen, Sclerotinia sclerotiorum, and identified 32 mutants with various developmental and growth deficiencies. Detailed molecular studies of three melanisation-deficient mutants provide a proof of concept for the effectiveness of our method. A master transcription factor was found to regulate melanisation of sclerotia through the DHN (1,8-dihydroxynaphthalene) melanin biosynthesis pathway. In addition, these mutants revealed that sclerotial melanisation is important for sclerotia survival under abiotic stresses, sclerotial surface structure, and sexual reproduction. Foreseeably, this pipeline can be applied to facilitate efficient in-depth studies of other non-model fungal species in the future.

Nicotinamide cofactors (e.g., NADH) are essential hydrogen sources for the majority of enzyme reduction reactions. Currently, highly efficient and in situ cofactor regeneration is urgently required but remains challenging. In this study, red phosphorus quantum dots were decorated onto graphitic carbon nitride hollow tubes to prepare high-performance heterojunction photocatalyst (g-C3N4-HTs@rP-QDs) for visible-light-driven NADH regeneration. Energy band analysis combined with photoelectrochemical measurements demonstrates rP-QDs not only act as additional photosensitizers for charge generation but also constitute a type II heterojunction with g-C3N4-HTs for charge transfer, facilitating enrichment of electrons on the g-C3N4-HTs surface. Such enrichment of electrons for g-C3N4-HTs@rP-QDs offers ∼5 times higher reducing active sites than bulk g-C3N4 to trigger the NADH regeneration reaction under visible-light (LED, 405 nm) illumination, thus acquiring superior NADH regeneration efficiency with an initial reaction rate (2 min) of 0.247 ± 0.012 mmol g–1 min–1. In the concerned experimental range, higher g-C3N4-HTs/rP-QDs mass ratios or light intensities that are beneficial for the electron enrichment could result in enhanced regeneration efficiency. The bioactivity of NADH toward enzyme catalysis is further demonstrated by alcohol dehydrogenase-catalyzed hydrogenation of formaldehyde, which enables the sustainable production of methanol.