Carbon Dioxide-Mediated Desalination.

Conventional desalination membrane technologies, although offer portable drinking water, are still energy-intensive processes. This paper proposes a potentially new approach for performing water desalination and purification by utilizing the reversible interaction of carbon dioxide (CO2) with nucleophilic amines─reminiscent of the Solvay process. Based on our model studies with small molecules, CO2-responsive amphiphilic insoluble diamines were prepared, characterized, and applied in the formation of soda and ammonium chloride upon exposure to ambient CO2 (1 atm), thus removing chloride ions from model and real seawater. This ion-exchange process and separation of chloride from the aqueous phase are spontaneous in the presence of CO2 without the need for external energy sources. We demonstrate a flow system to envisage energy-efficient CO2-mediated desalination and simultaneous carbon capture and sequestration.

Data Preprocessing and Augmentation Improved Visual Field Prediction of Recurrent Neural Network with Multi-Central Datasets.

INTRODUCTION: The purpose of this study was to determine whether data preprocessing and augmentation could improve visual field (VF) prediction of recurrent neural network (RNN) with multi-central datasets. METHODS: This retrospective study collected data from five glaucoma services between June 2004 and January 2021. From an initial dataset of 331,691 VFs, we considered reliable VF tests with fixed intervals. Since the VF monitoring interval is very variable, we applied data augmentation using multiple sets of data for patients with more than eight VFs. We obtained 5,430 VFs from 463 patients and 13,747 VFs from 1,076 patients by setting the fixed test interval to 365 ± 60 days (D = 365) and 180 ± 60 days (D = 180), respectively. Five consecutive VFs were provided to the constructed RNN as input and the 6th VF was compared with the output of the RNN. The performance of the periodic RNN (D = 365) was compared to that of an aperiodic RNN. The performance of the RNN with 6 long- and short-term memory (LSTM) cells (D = 180) was compared with that of the RNN with 5-LSTM cells. To compare the prediction performance, the root mean square error (RMSE) and mean absolute error (MAE) of the total deviation value (TDV) were calculated as accuracy metrics. RESULTS: The performance of the periodic model (D = 365) improved significantly over aperiodic model. Overall prediction error (MAE) was 2.56 ± 0.46 dB versus 3.26 ± 0.41 dB (periodic vs. aperiodic) (p < 0.001). A higher perimetric frequency was better for predicting future VF. The overall prediction error (RMSE) was 3.15 ± 2.29 dB versus 3.42 ± 2.25 dB (D = 180 vs. D = 365). Increasing the number of input VFs improved the performance of VF prediction in D = 180 periodic model (3.15 ± 2.29 dB vs. 3.18 ± 2.34 dB, p < 0.001). The 6-LSTM in the D = 180 periodic model was more robust to worsening of VF reliability and disease severity. The prediction accuracy worsened as the false-negative rate increased and the mean deviation decreased. CONCLUSION: Data preprocessing with augmentation improved the VF prediction of the RNN model using multi-center datasets. The periodic RNN model predicted the future VF significantly better than the aperiodic RNN model.

An ETS-NOCV-based computational strategies for the characterization of concerted transition states involving CO2.

Due to the presence of both a slightly acidic carbon and a slightly basic oxygen, carbon dioxide is often involved in concerted transition states (TSs) with two (or more) different molecular events interlaced in the same step. The possibility of isolating and quantitatively evaluating each molecular event would be important to characterize and understand the reaction mechanism in depth. This could be done, in principle, by measuring the relevant distances in the optimized TS, but often distances are not accurate enough, especially in the presence of many simultaneous processes. Here, we have applied the Extended Transition State-Natural Orbital for Chemical Valence-method (ETS-NOCV), also in combination with the Activation Strain Model (ASM) and Energy Decomposition Analysis (EDA), to separate and quantify these molecular events at the TS of both organometallic and organic reactions. For the former, we chose the decomposition of formic acid to CO2 by an iridium catalyst, and for the latter, a CO2 -mediated transamidation and its chemical variations (hydro- and aminolysis of an ester) as case studies. We demonstrate that the one-to-one mapping between the "molecular events" and the ETS-NOCV components is maintained along the entire lowest energy path connecting reactants and products around the TS, thus enabling a detailed picture on the relative importance of each interacting component. The methodology proposed here provides valuable insights into the effect of different chemical substituents on the reaction mechanism and promises to be generally applicable for any concerted TSs.

Cooperative Asymmetric Cation-Binding Catalysis.

Asymmetric cation-binding catalysis in principle enables the use of (alkali) metal salts, otherwise insoluble in organic solvents, as reagents and effectors in enantioselective reactions. However, this concept has been a formidable challenge due to the difficulties associated with creating a highly organized chiral environment for cations and anions simultaneously. Over the last four decades, various chiral crown ethers have been developed as cation-binding phase-transfer catalysts and examined in asymmetric catalysis. However, the limited ability of chiral crown ethers to generate soluble reactive anions in a confined chiral cage offers a restricted reaction scope and unsatisfactory chirality induction. To address the constraints of monofunctional chiral crown ethers as cation-binding catalysts, it is therefore desirable to develop a cooperative cation-binding catalyst possessing secondary binding sites for anions, which enables the generation of a reactive anion within a chiral cage of a catalyst. This account summarizes our design, development, and applications of chiral BINOL-based oligoethylene glycols (oligoEGs) as a new type of bifunctional cation-binding catalyst. We initially found that achiral oligoEGs were efficient promoters in nucleophilic fluorination with potassium fluoride. Thereby, we hypothesized that, by breaking the closed cyclic ether unit of chiral crown ethers, the free terminal -OH groups could activate the electrophiles by hydrogen bonding whereas the ether oxygens could act as the Lewis base to coordinate metal ions, thus generating soluble anions in a confined chiral cage. This hypothesis was realized by synthesizing a series of chiral variants of oligoEGs by connecting two 3,3'-disubstituted-BINOL units with glycol linkers. Readily available BINOL-based chiral oligoEGs enabled numerous asymmetric transformations out of the reach of chiral monofunctional crown ether catalysts. We have demonstrated that this new type of bifunctional cation-binding catalysts can generate a soluble fluoride anion from alkali metal fluorides, which can be a versatile chiral promoter for diverse asymmetric catalytic reactions, kinetic resolution (selectivity factor of up to ∼2300), asymmetric protonation, Mannich reactions, tandem cyclization reactions, and the isomerization of allylic alcohols and hemithioacetals. We have also successfully utilized our chiral oligoEG catalysts along with alkali metal salts of carbon- and heteroatom-based nucleophiles, respectively, for asymmetric Strecker reactions and the asymmetric synthesis of chiral aminals. The power of our cooperative cation-binding catalysis was exemplified by kinetic resolution reactions of secondary alcohols, achieving highly enantioselective catalysis with only <1 ppm loading of an organocatalyst with high TOFs (up to ∼1300 h-1 at 1 ppm catalyst loading). The broadness and generality of our cooperative asymmetric cation-binding catalysis can be ascribed, in a similar fashion, to active-site architectures of enzymes using allosteric interactions, highly confined chiral cages formed by the incorporation of alkali metal salts in the catalyst polyether chain backbone, and the cooperative activation of reacting partners by hydrogen-bonding and ion-ion interactions. Confining reactive components in such a chiral binding pocket leads to enhanced reactivity and efficient transfer of the stereochemical information.

Hydrogen peroxide signalling mediates fertilization and post-fertilization development in the red alga Bostrychia moritziana.

Reactive oxygen species (ROS) signalling has a multitude of roles in cellular processes throughout biology. We hypothesized that red algal fertilization may offer an interesting model to study ROS-mediated signalling, as the stages of fertilization are complex and unique. We detected the localization of ROS production microscopically and monitored the expression of three homologues of NADPH oxidase in reproductive cells during fertilization. ROS were instantaneously produced by spermatia (sperm) when they attached to female trichogynes, diffused across the cell membrane in the form of H2O2, and triggered ROS generation in the carpogonium (egg) as well as carpogonial branch cells which are not in direct contact with spermatia. The expression of NADPH oxidase homologues, RESPIRATORY BURST OXIDASE HOMOLOGUES (BmRBOHs), began to be up-regulated in the female plant upon gamete binding, peaking during the fertilization process and descending back to their original level after fertilization. Pre-treatment with diphenylene iodonium or caffeine blocked gene expression as well as H2O2 production. Post-fertilization development was also inhibited when the redox state of the plants was perturbed with H2O2 at any time before or after the fertilization. Our results suggest that H2O2 acts as an auto-propagating signalling molecule, possibly through Ca2+ channel activation, and regulates gene expression in fertilization as well as post-fertilization development in red algae.

Carbon dioxide enhances sulphur-selective conjugate addition reactions.

Sulphur-selective conjugate addition reactions play a central role in synthetic chemistry and chemical biology. A general tool for conjugate addition reactions should provide high selectivity in the presence of competing nucleophilic functional groups, namely nitrogen nucleophiles. We report CO2-mediated chemoselective S-Michael addition reactions where CO2 can reversibly control the reaction pHs, thus providing practical reaction conditions. The increased chemoselectivity for sulphur-alkylation products was ascribed to CO2 as a temporary and traceless protecting group for nitrogen nucleophiles, while CO2 efficiently provide higher conversion and selectivity sulphur nucleophiles on peptides and human serum albumin (HSA) with various electrophiles. This method offers simple reaction conditions for cysteine modification reactions when high chemoselectivity is required.

Evaluation of persistence and healthcare utilization in patients treated with anti-seizure medications as add-on therapy: A nationwide cohort study in South Korea.

OBJECTIVE: To compare medication adherence and healthcare utilization among patients who were treated with anti-seizure medications (ASMs) as first add-on to monotherapy for epilepsy using the national health insurance claims data. METHODS: A retrospective observational cohort study was conducted using the Korean National Health Insurance claims data. Patients who received ASM as first add-on to monotherapy during January 2017 to February 2018 were included. The selected patients were followed up for 12 months to evaluate persistence, adherence, and healthcare resource utilization. RESULTS: In total, 4277 patients who received ASM as first add-on to monotherapy for epilepsy were enrolled. The mean treatment duration of add-on ASM was 296.6 ±â€¯108.6 days during the 1-year follow-up period and 64.3% of the total population were persistent on the add-on ASM at 365 days from the index date. The mean medication possession ratio (MPR) was 90.3 ±â€¯23.7 and the proportion of adherent patients with ≥80% MPR was 79.3%. Lamotrigine (LTG), levetiracetam (LEV), oxcarbazepine (OXC), and perampanel (PER) groups showed significantly higher persistence and adherence than carbamazepine (CBZ), topiramate (TPM), and valproate (VAL) groups during the 1-year follow-up period. Significant differences in length of stays, total hospitalization cost, outpatient visit cost, and emergency cost were shown between ASM groups and LTG, LEV, OXC, and PER showed relatively low utilization and cost. CONCLUSIONS: Better adherence was observed in LTG, LEV, OXC, and PER groups than in CBZ, TPM, and VAL groups. Healthcare utilization and related costs showed significant difference between ASM groups.

The microbiomes of the eyelid and buccal area of patients with uveitic glaucoma.

BACKGROUND: The microbiome could trigger inflammation leading to epigenetic changes and is involved in the pathophysiology of eye diseases; however, its effect on uveitic glaucoma (UG) has not been fully investigated. This study analysed the differences in eyelid and buccal microbiomes in patients with UG using next-generation sequencing. METHODS: The eyelid and buccal specimens of 34 UG and 25 control patients were collected. The taxonomic composition of the microbiome was obtained via 16S ribosomal DNA sequencing. Diversity and differential gene expression analyses (DEG) determined taxon differences between the microbiomes of UG and control groups. RESULTS: In both the eyelid and buccal microbiomes, alpha-diversity was lower in UG patients than controls, while beta-diversity in patients with UG was higher than in controls. DEG analysis of the eyelid microbiome revealed various taxa differences, including enrichment of Paenibacillus and Dermacoccus (p-value, 1.31e-6 and 1.55e-7, respectively) and depletion of Morganella and Lactococcus (p-value, 6.26e-12 and 2.55e-6, respectively) in patients with UG. In the buccal microbiome, taxa such as Lactococcus was significantly depleted (p-value, 1.31e-17), whereas Faecalibacterium was enriched in patients with UG (p-value, 6.12e-8). CONCLUSIONS: The eyelid and buccal microbiomes in patients with UG differ from controls, which raises concerns surrounding environmental influences on the pathogenesis of UG. The reduced Lactococcus in the eyelid and buccal area suggest that microbiota dysbiosis is associated with UG.

Anomaly Detection Based on Time Series Data of Hydraulic Accumulator.

Although hydraulic accumulators play a vital role in the hydraulic system, they face the challenges of being broken by continuous abnormal pulsating pressure which occurs due to the malfunction of hydraulic systems. Hence, this study develops anomaly detection algorithms to detect abnormalities of pulsating pressure for hydraulic accumulators. A digital pressure sensor was installed in a hydraulic accumulator to acquire the pulsating pressure data. Six anomaly detection algorithms were developed based on the acquired data. A threshold averaging algorithm over a period based on the averaged maximum/minimum thresholds detected anomalies 2.5 h before the hydraulic accumulator failure. In the support vector machine (SVM) and XGBoost model that distinguish normal and abnormal pulsating pressure data, the SVM model had an accuracy of 0.8571 on the test set and the XGBoost model had an accuracy of 0.8857. In a convolutional neural network (CNN) and CNN autoencoder model trained with normal and abnormal pulsating pressure images, the CNN model had an accuracy of 0.9714, and the CNN autoencoder model correctly detected the 8 abnormal images out of 11 abnormal images. The long short-term memory (LSTM) autoencoder model detected 36 abnormal data points in the test set.

CO2 -Enabled Cyanohydrin Synthesis and Facile Iterative Homologation Reactions*.

Thermodynamic and kinetic control of a chemical process is the key to access desired products and states. Changes are made when a desired product is not accessible; one may manipulate the reaction with additional reagents, catalysts and/or protecting groups. Here we report the use of carbon dioxide to accelerate cyanohydrin synthesis under neutral conditions with an insoluble cyanide source (KCN) without generating toxic HCN. Under inert atmosphere, the reaction is essentially not operative due to the unfavored equilibrium. The utility of CO2 -mediated selective cyanohydrin synthesis was further showcased by broadening Kiliani-Fischer synthesis under neutral conditions. This protocol offers an easy access to a variety of polyols, cyanohydrins, linear alkylnitriles, by simply starting from alkyl- and arylaldehydes, KCN and an atmospheric pressure of CO2 .

A CO2-Catalyzed Transamidation Reaction.

Transamidation reactions are often mediated by reactive substrates in the presence of overstoichiometric activating reagents and/or transition metal catalysts. Here we report the use of CO2 as a traceless catalyst: in the presence of catalytic amounts of CO2, transamidation reactions were accelerated with primary, secondary, and tertiary amide donors. Various amine nucleophiles including amino acid derivatives were tolerated, showcasing the utility of transamidation in peptide modification and polymer degradation (e.g., Nylon-6,6). In particular, N,O-dimethylhydroxyl amides (Weinreb amides) displayed a distinct reactivity in the CO2-catalyzed transamidation versus a N2 atmosphere. Comparative Hammett studies and kinetic analysis were conducted to elucidate the catalytic activation mechanism of molecular CO2, which was supported by DFT calculations. We attributed the positive effect of CO2 in the transamidation reaction to the stabilization of tetrahedral intermediates by covalent binding to the electrophilic CO2.

Long-term efficacy and safety of perampanel as a first add-on therapy in patients with focal epilepsy: Three-year extension study.

PURPOSE: We investigated the long-term efficacy and safety of perampanel as a first add-on therapy in patients with focal epilepsy. METHODS: This retrospective study represented the 3-year extension phase of a multicenter, open-label, phase 4, prospective study of perampanel as a first add-on therapy in patients with focal epilepsy. Seizure and safety outcomes were assessed annually from the start of the extension study, and the retention rate was calculated from the start of perampanel exposure in the original study. RESULTS: The 50% responder and seizure freedom rates were 84.8% and 58.7%, respectively, during the third year and 71.7% and 32.6%, respectively, during the entire 3-year period of the extension study. The 1-, 2-, and 3-year retention rates were 62.5%, 53.1%, and 52.1%, respectively. Efficacies were higher in patients that were aged >55 years, male, and receiving ≤4 mg of perampanel. Perampanel was generally well tolerated; 47.3% of patients experienced at least one adverse event during the 3 years of extension (46 adverse events (AEs) in 35 patients). The most common AEs were dizziness (33.8%), somnolence (5.4%), anger (4.1%), and irritability (4.1%). AEs were resolved with perampanel dose reduction or discontinuation in 10 (13.5%) and 12 (16.2%) patients, respectively. CONCLUSION: Long-term treatment with perampanel as a first add-on therapy did not raise new safety signals in patients with focal epilepsy. Especially at low perampanel doses (≤4 mg/day), sustained improvement in seizure control was achieved, which could potentially avoid adverse drug reactions.

Differences in the eyelid and buccal microbiome of glaucoma patients receiving long-term administration of prostaglandin analog drops.

PURPOSE: To investigate the differences in the eyelid and buccal microbiomes between patients receiving long-term prostaglandin analogs for open-angle glaucoma (PG-OAG) and naïve-OAG patients by using metagenomics. METHODS: Eyelid and buccal samples were collected from 30 PG-OAG and 32 naïve-OAG patients. The taxonomic composition of the microbiome was obtained via 16S rRNA gene sequencing, operational taxonomic unit analysis, and diversity analysis. Differential gene expression analysis (DEG) and Bland-Altman (MA) plots were used to determine taxon differences between the microbiomes of PG-OAG and naïve-OAG patients. RESULTS: The eyelid microbiome showed marginally significant differences, while the alpha-diversity of the buccal microbiome showed significant differences between PG-OAG and naïve-OAG patients. However, the beta-diversity of both eyelid and buccal microbiomes was higher in PG-OAG patients than in naïve-OAG patients. The MA plot showed cluster differences in the eyelid microbiome. DEG analysis of the eyelid microbiome revealed various taxa differences, including enrichment of Azomonas, Pseudomonas, and Granulicatella in PG-OAG patients over naïve-OAG patients, as well as significant depletion of Delftia and Rothia. In the buccal microbiome in PG-OAG patients, taxa such as Rikenella and Stenotrophomonas were significantly enriched. CONCLUSION: Our findings suggest that the eyelid microbiome differs between PG-OAG and naïve-OAG patients, raising concerns regarding the eyelid environment in patients receiving these drugs. The overexpressed microbiome in the eyelid area suggests that microbiota may change after the administration of glaucoma medications in OAG.

First add-on perampanel for focal-onset seizures: An open-label, prospective study.

OBJECTIVES: This study aimed to determine the efficacy and safety of perampanel added to monotherapy in patients with focal-onset seizures, with or without secondarily generalized tonic-clonic seizures. MATERIALS & METHODS: In this multicentre, open-label trial, enrolled patients were treated with perampanel monotherapy. During a 12-week titration period, perampanel was incrementally increased by 2 mg/d over ≥2-week intervals. Patients then entered a 24-week maintenance period. The primary objective was to investigate the 50% responder rate in total seizure frequency, with 75% and 100% responder rates as secondary objectives. Treatment-emergent adverse events (TEAEs) and adverse drug reactions were recorded. A post hoc analysis was performed to investigate the effect of titration speed and different concomitant AEDs on the efficacy and safety of perampanel. RESULTS: Of the 85 patients analysed, seizure reductions of 50%, 75% and 100% were observed in 80.0% (95% confidence interval [CI]: 69.9-87.9), 71.8% (95% CI: 61.0-81.0) and 47.1% (95% CI: 36.1-58.2) during the maintenance period, respectively. The 50%, 75% and 100% response rates in patients with secondarily generalized tonic-clonic seizures were 87.5% (95% CI: 61.7-98.5), 87.5% (95% CI: 61.7-98.5) and 75.0% (95% CI: 47.6-92.7), respectively. The most common TEAEs were dizziness (50.0%), somnolence (9.8%) and headache (8.8%). The efficacy outcomes and safety profile of perampanel were more favourable with slow titration and relatively consistent when stratified by concomitant AEDs. CONCLUSIONS: Perampanel was effective and well tolerated as a first add-on to monotherapy in patients with focal-onset seizures, with or without secondarily generalized seizures.

Homocoupling Reactions of Azoles and Their Applications in Coordination Chemistry.

Pyrazole, a member of the structural class of azoles, exhibits molecular properties of interest in pharmaceuticals and materials chemistry, owing to the two adjacent nitrogen atoms in the five-membered ring system. The weakly basic nitrogen atoms of deprotonated pyrazoles have been applied in coordination chemistry, particularly to access coordination polymers and metal-organic frameworks, and homocoupling reactions can in principle provide facile access to bipyrazole ligands. In this context, we summarize recent advances in homocoupling reactions of pyrazoles and other types of azoles (imidazoles, triazoles and tetrazoles) to highlight the utility of homocoupling reactions in synthesizing symmetric bi-heteroaryl systems compared with traditional synthesis. Metal-free reactions and transition-metal catalyzed homocoupling reactions are discussed with reaction mechanisms in detail.

Red And far-red regulation of filament movement correlates with the expression of phytochrome and FHY1 genes in Spirogyra varians (Zygnematales, Streptophyta)1.

Spirogyra filaments show unique photomovement that differs in response to blue, red, and far-red light. Phototropins involved in the blue-light movement have been characterized together with downstream signaling components, but the photoreceptors and mechanical effectors of red- and far-red light movement are not yet characterized. The filaments of Spirogyra varians slowly bent and aggregated to form a tangled mass in red light. In far-red light, the filaments unbent, stretched rapidly, and separated from each other. Mannitol and/or sorbitol treatment significantly inhibited this far-red light movement suggesting that turgor pressure is the driving force of this movement. The bending and aggregating movements of filaments in red light were not affected by osmotic change. Three phytochrome homologues isolated from S. varians showed unique phylogenetic characteristics. Two canonical phytochromes, named SvPHY1 and SvPHY2, and a noncanonical phytochrome named SvPHYX2. SvPHY1 is the first PHY1 family phytochrome reported in zygnematalean algae. The gene involved in the transport of phytochromes into the nucleus was characterized, and its expression in response to red and far-red light was measured using quantitative PCR. Our results suggest that the phytochromes and the genes involved in the transport system into the nucleus are well conserved in S. varians.

Asymmetric Aminalization via Cation-Binding Catalysis.

Asymmetric cation-binding catalysis, in principle, can generate "chiral" anionic nucleophiles, where the counter cations are coordinated within chiral environments. Nitrogen nucleophiles are intrinsically basic, therefore, its use as nucleophiles is often challenging and limiting the scope of the reaction. Particularly, a formation of configurationally labile aminal centers with alkyl substituents has been a formidable challenge due to the enamine/imine equilibrium of electrophilic substrates. Herein, we report enantioselective nucleophilic addition reactions of potassium phthalimides to Boc-protected alkyl- and aryl-substituted α-amido sulfones. In situ generated imines smoothly reacted with the nitrogen nucleophiles to corresponding aminals with good to excellent enantioselectivitiy under mild reaction conditions. In addition, transformation of aminal products gave biologically relevant pyrrolidinone-fused hexahydropyrimidine scaffold with excellent stereoselectivity and good yield.

Radiometallic Complexes of DO3A-Benzothiazole Aniline for Nuclear Medicine Theranostics.

To develop a radioactive metal complex platform for tumor theranostics, we introduced three radiopharmaceutical derivatives of 1,4,7,10-tetraazacyclododecane-1,4,7-trisacetic acid-benzothiazole aniline (DO3A-BTA, L1) labeled with medical radioisotopes for diagnosis (68Ga/64Cu) and therapy (177Lu). The tumor-targeting ability of these complexes was demonstrated in a cellular uptake experiment, in which 177Lu-L1 exhibited markedly higher uptake in HeLa cells than the 177Lu-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid complex. According to in vivo positron emission tomography imaging, high accumulation of 68Ga-L1 and 64Cu-L1 was clearly visualized in the tumor site, while 177Lu-L1 showed therapeutic efficacy in therapy experiments. Consequently, this molecular platform represents a useful approach in nuclear medicine toward tumor-theranostic radiopharmaceuticals when 68Ga-L1 or 64Cu-L1 is used for diagnosis, 177Lu-L1 is used for therapy, or two of the compounds are used in conjunction with each other.

Umpolung Reactivity of Aldehydes toward Carbon Dioxide.

Carbon dioxide is an intrinsically stable molecule. Therefore, its activation requires extra energy input in the form of reactive reagents and/or activated catalysts and, often, harsh reaction conditions. Reported here is a direct carboxylation reaction of aromatic aldehydes with carbon dioxide to afford α-keto acids as added-value products. In situ generation of a reactive cyanohydrin was the key to the successful carboxylation reaction under operationally mild reaction conditions (25-40 °C, 1 atm CO2 ). The resulting α-keto acids served as a platform for α-amino acid synthesis by reductive amination reactions, illustrating the chemical synthesis of essential bioactive molecules from carbon dioxide.

Two-Track Control of Cellular Machinery for Photomovement in Spirogyra varians (Streptophyta, Zygnematales).

Plants and freshwater algae devoid of flagella evolved various photomovements to optimize their photosynthetic efficiency. The filaments of Spirogyra varians exhibit complex swaying and undulating movement and form a compact mat which enables them to adjust their light exposure. Photomovement of filament fragments (1-10 cells) was analyzed using various photoreceptor and cytoskeleton inhibitors under monochromatic light. Different patterns of movement were observed under red and blue light. The filaments showed positive phototropism under blue light. Under red light, the filaments bent to undulating shape, but rapidly became unbent by a short exposure to far-red light suggesting the involvement of phytochrome in this movement. The mechanical effector for the red-light response was microtubules; the movement was inhibited effectively by the microtubule inhibitor, oryzalin. The blue-light movement was partially inhibited by the single treatment of either cytochalasin D or oryzalin, but was completely blocked when both chemicals were applied together. Phototropin-signaling inhibitors, wortmannin and LY294002, reversibly inhibited the blue-light movement. Caffeine treatment reversibly stopped the blue-light movement, while the red-light movement was not affected by calcium inhibitors. Our results suggest that the complex photomovement of S. varians is the result of a two-track control of microtubules and microfilaments signaled by the combination of phytochrome and phototropin-like receptors.