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In nature, plants convert solar energy into chemical energy via water oxidation. Inspired by natural photosynthesis, artificial photosynthesis has been gaining increasing interest in the field of sustainability/green science and technology as a non-natural and thermodynamically endergonic (Δ G ° > 0, uphill) solar-energy-driven reaction that uses water as an electron donor and a source material. Among the artificial-photosynthesis processes, inorganic-synthesis reactions via water oxidation, including water splitting and CO 2 -to-fuel conversion, have been attracting much attention. In contrast, the synthesis of high-value functionalized organic compounds via artificial photosynthesis, which we have termed artificial photosynthesis directed toward organic synthesis (APOS), remains a great challenge. Herein, we report a synthetically pioneering and meaningful strategy of APOS, where the carbohydroxylation of C = C double bonds is accomplished via a three-component coupling with H 2 evolution using dual functions of semiconductor photocatalysts, i.e., silver-loaded titanium dioxide (Ag/TiO 2 ) and rhodium–chromium–cobalt-loaded aluminum-doped strontium titanate (RhCrCo/SrTiO 3 :Al). Emulating the concept of natural photosynthesis has long been a focus of chemists in an effort to harness solar light as an energy source using water as an electron donor and a source material. Here, the authors present an artificial photosynthetic system that can functionalize styrenes via C–H activation and water splitting.

Controlled halogenation of chemically versatile substrates is difficult to achieve. Here we describe a unique flavin-dependent halogenase, PltM, which is capable of utilizing a wide range of halides for installation on a diverse array of phenolic compounds, including FDA-approved drugs and natural products, such as terbutaline, fenoterol, resveratrol, and catechin. Crystal structures of PltM in complex with phloroglucinol and FAD in different states yield insight into substrate recognition and the FAD recycling mechanism of this halogenase. Halogenase enzymes are of interest as halogenating tools for organic synthesis. Here the authors show that the bacterial FAD-dependent phenolic halogenase PltM chlorinates, brominates and iodinates a variety of substrates and reveal the structural basis for its substrate versatility and provide insights into the FAD recycling mechanism of PltM.

Interrupted adenylation domains are enigmatic fusions, in which one enzyme is inserted into another to form a highly unusual bifunctional enzyme. We present the first crystal structure of an interrupted adenylation domain that reveals a unique embedded methyltransferase. The structure and functional data provide insight into how these enzymes N-methylate amino acid precursors en route to nonribosomal peptides.

Natural cyclic peptides, a diverse class of bioactive compounds, have been isolated from various natural sources and are renowned for their extensive structural variability and broad spectrum of medicinal properties. Over 40 cyclic peptides or their derivatives are currently approved as medicines, underscoring their significant therapeutic potential. These compounds are employed in diverse roles, including antibiotics, antifungals, antiparasitics, immune modulators, and anti-inflammatory agents. Their unique ability to combine high specificity with desirable pharmacokinetic properties makes them valuable tools in addressing unmet medical needs, such as combating drug-resistant pathogens and targeting challenging biological pathways. Due to the typically low concentrations of cyclic peptides in nature, effective synthetic strategies are indispensable for their acquisition, characterization, and biological evaluation. Cyclization, a critical step in their synthesis, enhances metabolic stability, bioavailability, and receptor binding affinity. Advances in synthetic methodologies—such as solid-phase peptide synthesis (SPPS), chemoenzymatic approaches, and orthogonal protection strategies—have transformed cyclic peptide production, enabling greater structural complexity and precision. This review compiles recent progress in the total synthesis and biological evaluation of natural cyclic peptides from 2017 onward, categorized by cyclization strategies: head-to-tail; head-to-side-chain; tail-to-side-chain; and side-chain-to-side-chain strategies. Each account includes retrosynthetic analyses, synthetic advancements, and biological data to illustrate their therapeutic relevance and innovative methodologies. Looking ahead, the future of cyclic peptides in drug discovery is bright. Emerging trends, including integrating computational tools for rational design, novel cyclization techniques to improve pharmacokinetic profiles, and interdisciplinary collaboration among chemists, biologists, and computational scientists, promise to expand the scope of cyclic peptide-based therapeutics. These advancements can potentially address complex diseases and advance the broader field of biological drug development.

The Japanese rhinoceros beetle Trypoxylus dichotomus is a giant beetle with distinctive exaggerated horns present on the head and prothoracic regions of the male. T. dichotomus has been used as a research model in various fields such as evolutionary developmental biology, ecology, ethology, biomimetics, and drug discovery. In this study, de novo assembly of 615 Mb, representing 80% of the genome estimated by flow cytometry, was obtained using the 10 × Chromium platform. The scaffold N50 length of the genome assembly was 8.02 Mb, with repetitive elements predicted to comprise 49.5% of the assembly. In total, 23,987 protein-coding genes were predicted in the genome. In addition, de novo assembly of the mitochondrial genome yielded a contig of 20,217 bp. We also analyzed the transcriptome by generating 16 RNA-seq libraries from a variety of tissues of both sexes and developmental stages, which allowed us to identify 13 co-expressed gene modules. We focused on the genes related to horn formation and obtained new insights into the evolution of the gene repertoire and sexual dimorphism as exemplified by the sex-specific splicing pattern of the doublesex gene. This genomic information will be an excellent resource for further functional and evolutionary analyses, including the evolutionary origin and genetic regulation of beetle horns and the molecular mechanisms underlying sexual dimorphism.

The original version of this Article contained an error in Fig. 1, in which the labels ‘NADP + ’ and ‘NADPH + H + ’ were incorrectly given as ‘NADPH’ and ‘NADPH + + H + ’, respectively. This has been corrected in both the PDF and HTML versions of the Article.

We designed and synthesized two zinc phthalocyanine sensitizers (PcS27 and PcS28), substituted with branched or cyclic alkoxy chains, to investigate the structural effect of peripheral alkyl chains on the performance of dye-sensitized TiO2 solar cells. The bulky cyclic alkyl chains of PcS28 decreased the adsorption density of PcS28 on the TiO2 electrode, while the terminal branches of alkoxy chains of PcS27 did not influence the adsorption density in comparison to the previously published PcS20 with linear alkoxy chains. Under one sun conditions, PcS27 cells exhibited higher open-circuit voltage but a slightly lower energy conversion efficiency, 6.0% less than PcS20. These results suggest that the small alternation of alkoxy chains resulted in decreasing electron pushing ability of peripheral phenoxy units, giving lower short-circuit current.

A new bioactive macrolactone, nuiapolide (1) was identified from a marine cyanobacterium collected off the coast of Niihau, near Lehua Rock. The natural product exhibits anti-chemotactic activity at concentrations as low as 1.3 μM against Jurkat cells, cancerous T lymphocytes, and induces a G2/M phase cell cycle shift. Structural characterization of the natural product revealed the compound to be a 40-membered macrolactone with nine hydroxyl functional groups and a rare tert-butyl carbinol residue.

Organisms have evolved under the gravitational force and sense the direction of gravity via statoliths in specialized cells. In the gravitropism of flowering plants, the starch-accumulating plastids, amyloplasts, in gravity sensing cells act as statoliths. The gravity sensing mechanism has long been considered a mechanosensing process by which amyloplasts transmit forces to intracellular structures, but the molecular support has not been reported. This study revealed that LAZY1-LIKE family proteins involved in gravity signaling in statocytes are localized to the amyloplast periphery and its proximal plasma membrane, resulting in polar localization according to the direction of gravity. We propose a gravity sensing mechanism by which LZY transmits the positional information of amyloplasts, i.e., the direction of gravity, by translocating to the plasma membrane.

The utilization of natural products as therapeutic agents has been an invaluable resource throughout medicinal history. Through the combined application of combinatorial biosynthesis, the modification of a natural product by engineered enzymes, and the isolation of new bioactive natural products, the discovery of new therapeutic agents may be achieved. This work shows the novel enzymatic interaction in the biosynthesis of a known therapeutic agent and the isolation of a new bioactive natural product. Azinomycin A and B are antitumor natural products, isolated from Streptomyces sahachiroi. It was proposed that the biosynthesis of azinomycins is achieved through polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) machinery. In order to characterize the role of the PKS (AziB), enzymatic assays were analyzed by HPLC, LC-MS, and spectrophotometric methods. Although AziB was predicted to catalyze the production of 5-methyl-1-napthoic acid, a building block of azinomycins, a thioesterase (AziG) was found to be essential. Kinetic and crystallographic studies suggested the importance of the interaction of AziB and AziG to facilitate optimal enzymatic activity. The derivative of the AziB-AziG product is hypothesized to be assembled into the azinomycin backbone by NRPSs. In order to confirm the significance of a NRPS (AziA2) in the azinomycin biosynthetic pathway, gene knockout studies were performed. Fermentation of ΔaziA2 S. sahachiroi led to an cryptic overproduction of dimethyl furan-2,4-dicarboxylate. This showed an example of bacterial adaptation where bacteria start overproducing a new secondary metabolite to deal with the absence of a bioactive natural product. A novel bioactive 40-membered macrolactone, Nuiapolide, was identified from a cyanobacterium collected from the Hawaiian ocean. This molecule has a rare tert-butyl side chain and nine hydroxyl groups distributed through the large hydrocarbon ring structure. Nuiapolide could inhibit metastatic activity of Jurkat at the concentration of as low as 1.3 μM without killing the cells. In this dissertation, the new functionality of a class of enzyme, the effect of biosynthetic disruption, and a novel anti-metastatic natural product from a marine source will be discussed. This information leads to a new understanding of natural products and their biosynthesis, which will eventually help researchers developing novel therapeutic agents.