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Cyanobacteriota, the sole prokaryotes capable of oxygenic photosynthesis (OxyP), occupy a unique and pivotal role in Earth's history. While the notion that OxyP may have originated from Cyanobacteriota is widely accepted, its early evolution remains elusive. Here, by using both metagenomics and metatranscriptomics, we explore 36 metagenome-assembled genomes from hot spring ecosystems, belonging to two deep-branching cyanobacterial orders: Thermostichales and Gloeomargaritales. Functional investigation reveals that Thermostichales encode the crucial thylakoid membrane biogenesis protein, vesicle-inducing protein in plastids 1 (Vipp1). Based on the phylogenetic results, we infer that the evolution of the thylakoid membrane predates the divergence of Thermostichales from other cyanobacterial groups and that Thermostichales may be the most ancient lineage known to date to have inherited this feature from their common ancestor. Apart from OxyP, both lineages are potentially capable of sulfide-driven AnoxyP by linking sulfide oxidation to the photosynthetic electron transport chain. Unexpectedly, this AnoxyP capacity appears to be an acquired feature, as the key gene sqr was horizontally transferred from later-evolved cyanobacterial lineages. The presence of two D1 protein variants in Thermostichales suggests the functional flexibility of photosystems, ensuring their survival in fluctuating redox environments. Furthermore, all MAGs feature streamlined phycobilisomes with a preference for capturing longer-wavelength light, implying a unique evolutionary trajectory. Collectively, these results reveal the photosynthetic flexibility in these early-diverging cyanobacterial lineages, shedding new light on the early evolution of Cyanobacteriota and their photosynthetic processes.
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Cianobactérias , Fotossíntese , Fotossíntese/genética , Cianobactérias/genética , Cianobactérias/metabolismo , Evolução Biológica , Filogenia , Oxigênio/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Evolução MolecularRESUMO
Biodegradation stands as an eco-friendly and effective approach for organic contaminant remediation. However, research on microorganisms degrading sodium benzoate contaminants in extreme environments remains limited. In this study, we report to display the isolation of a novel hot spring enriched cultures with sodium benzoate (400 mg/L) as the sole carbon source. The results revealed that the phylum Pseudomonadota was the potential sodium benzoate degrader and a novel genus within the family Geminicoccaceae of this phylum. The isolated strain was named Benzoatithermus flavus SYSU G07066T and was isolated from HNT-2 hot spring samples. Genomic analysis revealed that SYSU G07066T carried benABC genes and physiological experiments indicated the ability to utilize sodium benzoate as a sole carbon source for growth, which was further confirmed by transcriptomic data with expression of benABC. Phylogenetic analysis suggested that Horizontal Gene Transfer (HGT) plays a significant role in acquiring sodium benzoate degradation capability among prokaryotes, and SYSU G07066T might have acquired benABC genes through HGT from the family Acetobacteraceae. The discovery of the first microorganism with sodium benzoate degradation function from a hot spring enhances our understanding of the diverse functions within the family Geminicoccaceae. This study unearths the first novel genus capable of efficiently degrading sodium benzoate and its evolution history at high temperatures, holding promising industrial applications, and provides a new perspective for further exploring the application potential of hot spring "microbial dark matter".
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Biodegradação Ambiental , Fontes Termais , Filogenia , Benzoato de Sódio , Benzoato de Sódio/metabolismo , Fontes Termais/microbiologia , Poluentes Químicos da Água/metabolismo , MultiômicaRESUMO
The wavelength-dependent dynamics of the O(1D2) channel, formed by photoexcitation of CO2 to the 1Δu state at 143.53-153.03 nm, is investigated by using the time-sliced velocity-mapped ion imaging method. The measured ionic peaks of the O(1D2) images are analyzed to determine the total kinetic energy release (TKER) spectra and image anisotropy parameters. The structures observed in the TKER spectra can be directly assigned to the ro-vibrational state distributions of the counter CO photofragments. Compared to those observed at 157 and 155 nm, the highly rotationally excited CO photofragments still obviously appear in v = 0 and 1, but the fraction of rotational excitations is significantly reduced. Conversely, the CO photofragments exhibit substantially higher vibrational excitations, implying that the nearly linear 21A' state also contributes to dissociation in addition to the bend configuration. The image anisotropy parameters display an extremely slow decreasing trend with an increase of the CO ro-vibrational state besides those for the highest ro-vibrationally excited CO photofragments. Nevertheless, the nonaxial recoil effect, suggested in previous photodissociation studies of CO2 and other triatomic molecular systems, is still appropriate to explain the observations of internal energy dependences of image anisotropy parameters.
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Lithium metal batteries (LMB) have high energy densities and are crucial for clean energy solutions. The characterization of the lithium metal interphase is fundamentally and practically important but technically challenging. Taking advantage of synchrotron X-ray, which has the unique capability of analyzing crystalline/amorphous phases quantitatively with statistical significance, we study the composition and dynamics of the LMB interphase for a newly developed important LMB electrolyte that is based on fluorinated ether. Pair distribution function analysis revealed the sequential roles of the anion and solvent in interphase formation during cycling. The relative ratio between Li2O and LiF first increases and then decreases during cycling, suggesting suppressed Li2O formation in both initial and long extended cycles. Theoretical studies revealed that in initial cycles, this is due to the energy barriers in many-electron transfer. In long extended cycles, the anion decomposition product Li2O encourages solvent decomposition by facilitating solvent adsorption on Li2O which is followed by concurrent depletion of both. This work highlights the important role of Li2O in transitioning from an anion-derived interphase to a solvent-derived one.
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Lithium metal batteries represent a promising technology for next-generation energy storage, but they still suffer from poor cycle life due to lithium dendrite formation and cathode cracking. Fluorinated solvents can improve battery longevity by improving LiF content in the solid-electrolyte interphase; however, the high cost and environmental concerns of fluorinated solvents limit battery viability. Here we designed a series of fluorine-free solvents through the methylation of 1,2-dimethoxyethane, which promotes inorganic LiF-rich interphase formation through anion reduction and achieves high oxidation stability. The anion-derived LiF interphases suppress lithium dendrite growth on the lithium anode and minimize cathode cracking under high-voltage operation. The Li+-solvent structure is investigated through in situ techniques and simulations to draw correlations between the interphase compositions and electrochemical performances. The methylation strategy provides an alternative pathway for electrolyte engineering towards high-voltage electrolytes while reducing dependence on expensive fluorinated solvents.
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Solid-state Li-S batteries (SSLSBs) are made of low-cost and abundant materials free of supply chain concerns. Owing to their high theoretical energy densities, they are highly desirable for electric vehicles1-3. However, the development of SSLSBs has been historically plagued by the insulating nature of sulfur4,5 and the poor interfacial contacts induced by its large volume change during cycling6,7, impeding charge transfer among different solid components. Here we report an S9.3I molecular crystal with I2 inserted in the crystalline sulfur structure, which shows a semiconductor-level electrical conductivity (approximately 5.9 × 10-7 S cm-1) at 25 °C; an 11-order-of-magnitude increase over sulfur itself. Iodine introduces new states into the band gap of sulfur and promotes the formation of reactive polysulfides during electrochemical cycling. Further, the material features a low melting point of around 65 °C, which enables repairing of damaged interfaces due to cycling by periodical remelting of the cathode material. As a result, an Li-S9.3I battery demonstrates 400 stable cycles with a specific capacity retention of 87%. The design of this conductive, low-melting-point sulfur iodide material represents a substantial advancement in the chemistry of sulfur materials, and opens the door to the practical realization of SSLSBs.
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A Gram-stain-negative, non-endospore-forming, motile, short rod-shaped strain, designated SYSU G07232T, was isolated from a hot spring microbial mat, sampled from Rehai National Park, Tengchong, Yunnan Province, south-western China. Strain SYSU G07232T grew at 25-50â°C (optimum, 37â°C), at pH 5.5-9.0 (optimum, pH 6.0) and tolerated NaCl concentrations up to 1.0â% (w/v). Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain SYSU G07232T showed closest genetic affinity with Chelatococcus daeguensis K106T. The genomic features and taxonomic status of this strain were determined through whole-genome sequencing and a polyphasic approach. The predominant quinone of this strain was Q-10. Major cellular fatty acids comprised C19â:â0 cyclo ω8c and summed feature 8. The whole-genome length of strain SYSU G07232T was 4.02 Mbp, and the DNA G+C content was 69.26âmol%. The average nucleotide identity (ANIm ≤84.85â% and ANIb ≤76.08ââ%) and digital DNA-DNA hybridization (≤ 21.9â%) values between strain SYSU G07232T and the reference species were lower than the threshold values recommended for distinguishing novel prokaryotic species. Thus, based on the provided phenotypic, phylogenetic, and genetic data, it is proposed that strain SYSU G07232T (=KCTC 8141T=GDMCC 1.4178T) be designated as representing a novel species within the genus Chelatococcus, named Chelatococcus albus sp. nov.
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Beijerinckiaceae , Fontes Termais , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , China , Ácidos Graxos/química , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , BactériasRESUMO
Micro-sized silicon anodes can significantly increase the energy density of lithium-ion batteries with low cost. However, the large silicon volume changes during cycling cause cracks for both organic-inorganic interphases and silicon particles. The liquid electrolytes further penetrate the cracked silicon particles and reform the interphases, resulting in huge electrode swelling and quick capacity decay. Here we resolve these challenges by designing a high-voltage electrolyte that forms silicon-phobic interphases with weak bonding to lithium-silicon alloys. The designed electrolyte enables micro-sized silicon anodes (5 µm, 4.1 mAh cm-2) to achieve a Coulombic efficiency of 99.8% and capacity of 2175 mAh g-1 for >250 cycles and enable 100 mAh LiNi0.8Co0.15Al0.05O2 pouch full cells to deliver a high capacity of 172 mAh g-1 for 120 cycles with Coulombic efficiency of >99.9%. The high-voltage electrolytes that are capable of forming silicon-phobic interphases pave new ways for the commercialization of lithium-ion batteries using micro-sized silicon anodes.
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Li metal batteries using Li metal as negative electrode and LiNi1-x-yMnxCoyO2 as positive electrode represent the next generation high-energy batteries. A major challenge facing these batteries is finding electrolytes capable of forming good interphases. Conventionally, electrolyte is fluorinated to generate anion-derived LiF-rich interphases. However, their low ionic conductivities forbid fast-charging. Here, we use CsNO3 as a dual-functional additive to form stable interphases on both electrodes. Such strategy allows the use of 1,2-dimethoxyethane as the single solvent, promising superior ion transport and fast charging. LiNi1-x-yMnxCoyO2 is protected by the nitrate-derived species. On the Li metal side, large Cs+ has weak interactions with the solvent, leading to presence of anions in the solvation sheath and an anion-derived interphase. The interphase is surprisingly dominated by cesium bis(fluorosulfonyl)imide, a component not reported before. Its presence suggests that Cs+ is doing more than just electrostatic shielding as commonly believed. The interphase is free of LiF but still promises high performance as cells with high LiNi0.8Mn0.1Co0.1O2 loading (21 mg/cm2) and low N/P ratio (~2) can be cycled at 2C (~8 mA/cm2) with above 80% capacity retention after 200 cycles. These results suggest the role of LiF and Cs-containing additives need to be revisited.
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Reversible lattice oxygen redox reactions offer the potential to enhance energy density and lower battery cathode costs. However, their widespread adoption faces obstacles like substantial voltage hysteresis and poor stability. The current research addresses these challenges by achieving a non-hysteresis, long-term stable oxygen redox reaction in the P3-type Na2/3Cu1/3Mn2/3O2. Here we show this is accomplished by forming spin singlet states during charge and discharge. Detailed analysis, including in-situ X-ray diffraction, shows highly reversible structural changes during cycling. In addition, local CuO6 Jahn-Teller distortions persist throughout, with dynamic Cu-O bond length variations. In-situ hard X-ray absorption and ex-situ soft X-ray absorption study, along with density function theory calculations, reveal two distinct charge compensation mechanisms at approximately 3.66 V and 3.99 V plateaus. Notably, we observe a Zhang-Rice-like singlet state during 3.99 V charging, offering an alternative charge compensation mechanism to stabilize the active oxygen redox reaction.
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Prussian blue analogues (PBAs) used as sodium ion battery (SIB) cathodes are usually the focus of attention due to their three-dimensional open frame and high theoretical capacity. Nonetheless, the disadvantages of a low working voltage and inferior structural stability of PBAs prevent their further applications. Herein, we propose constructing the Kx(MnFeCoNiCu)[Fe(CN)6] (HE-K-PBA) cathode by high-entropy and potassium incorporation strategy to simultaneously realize high working voltage and cycling stability. The reaction mechanism of metal cations in HE-K-PBA are revealed by synchrotron radiation X-ray absorption spectroscopy (XAS), ex situ X-ray photoelectron spectroscopy (XPS), and in situ Raman spectra. We also investigate the entropy stabilization mechanism via finite element simulation, demonstrating that HE-K-PBA with small von Mises stress and weak structure strain can significantly mitigate the structural distortion. Benefit from the stable structure and everlasting K+ (de)intercalation, the HE-K-PBA delivers high output voltage (3.46 V), good reversible capacity (120.5 mAh g-1 at 0.01 A g-1), and capacity retention of 90.4% after 1700 cycles at 1.0 A g-1. Moreover, the assembled full cell and all-solid-state batteries with a stable median voltage of 3.29 V over 3000 cycles further demonstrate the application prospects of the HE-K-PBA cathode.
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This study investigated the effects of three oil production methods on the physicochemical properties of dietary fiber from rice bran flour, and the hypolipidemic effects of the dietary fibers were investigated in vitro and in vivo. The particle size results showed that the organic-solvent-impregnated rice bran meal dietary fiber (N-RBDF) had the smallest average particle size and the aqueous enzymatic rice bran meal dietary fiber (E-RBDF) had the narrowest particle size distribution. Scanning electron microscopy (SEM) results demonstrated that all three kinds of rice bran meal dietary fibers (RBDFs) were irregularly flaky. Fourier transform infrared spectroscopy (FT-IR) results revealed that the three RBDFs had similar reactive groups, and X-ray diffraction (XRD) results indicated that all three RBDFs were cellulose type I crystals. The results of thermogravimetric analysis showed that the lignin content of N-RBDF was significantly lower than that of the other two. Among the three kinds of RBDFs, E-RBDF had higher water retention capacity, swelling capacity, oil holding capacity, and adsorption capacity for cholesterol and sodium bile salts. The results of experimental studies in hyperlipidemic rats showed that all three kinds of RBDFs significantly reduced triglycerides (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) and elevated high-density lipoprotein cholesterol (HDL-C) in the serum of hyperlipidemic rats; they also significantly lowered malondialdehyde (MDA) and elevated total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) activities in the livers of rats. In addition, all three kinds of RBDFs decreased aminotransferase (ALT) and aminotransferase (AST) activity in serum and also improved liver steatosis and reduced atherosclerosis index (AI) in rats with hyperlipidemia. Our study provides a reference for the development and utilization of rice bran meal and the application of rice bran meal dietary fiber in food processing.
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Mercury (Hg) biotransformation (methylation and demethylation) could play a key role in affecting the final Hg speciation and level in fish. The gut microbiota was identified to be involved in this process. Diet is recognized to greatly influence the gut microbiome, whereas the impact of food composition on Hg biotransformation in fish has yet to be addressed. The study investigated the biotransformation and bioaccumulation of Hg in the gobyfish (Mugilogobius chulae) under different food choices (natural prey and artificial food) and evaluated the role of gut microbiome in these processes. The results showed that different diet composition significantly affected the gut microbiome and subsequently resulted in varied phenomenon of Hg biotransformation within fish body. Significant demethylation (0.33 % d-1) was only observed in the natural prey (brine shrimp) treatment, whereas methylation was occurred extremely slowly (0.013 % d-1) only in the artificial food (commercial dry pellets) treatment. Furthermore, the growth of demethylators was also enhanced in the natural prey treatment, which contributed to the demethylation process in fish. Furthermore, the gut microbial structure of gobyfish was greatly altered by different diet composition. This study highlights the significance of food choices in the minimization of Hg contamination in aquaculture. Incorporating natural prey into fish diets could be a better choice to balance the fish production and control MeHg levels. CAPSULE: Diet composition greatly affects the gut microbial composition, and natural prey could help to reduce the potential of MeHg accumulation by fish.
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Microbioma Gastrointestinal , Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Animais , Mercúrio/análise , Poluentes Químicos da Água/análise , Peixes/metabolismo , Dieta/veterinária , Biotransformação , Compostos de Metilmercúrio/metabolismoRESUMO
Sodium-ion batteries have garnered unprecedented attention as an electrochemical energy storage technology, but it remains challenging to design high-energy-density cathode materials with low structural strain during the dynamic (de)sodiation processes. Herein, we report a P2-layered lithium dual-site-substituted Na0.7Li0.03[Mg0.15Li0.07Mn0.75]O2 (NMLMO) cathode material, in which Li ions occupy both transition-metal (TM) and alkali-metal (AM) sites. The combination of theoretical calculations and experimental characterizations reveals that LiTM creates Na-O-Li electronic configurations to boost the capacity derived from the oxygen anionic redox, while LiAM serves as LiO6 prismatic pillars to stabilize the layered structure through suppressing the detrimental phase transitions. As a result, NMLMO delivers a high specific capacity of 266 mAh g-1 and simultaneously exhibits the nearly zero-strain characteristic within a wide voltage range of 1.5-4.6 V. Our findings highlight the effective way of dual-site substitution to break the capacity-stability trade-off in cathode materials for advanced rechargeable batteries.
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The recent discovery of Nitrospira species capable of complete ammonia oxidation (comammox) in non-marine natural and engineered ecosystems under mesothermal conditions has changed our understanding of microbial nitrification. However, little is known about the occurrence of comammox bacteria or their ability to survive in moderately thermal and/or hyperthermal habitats. Here, we report the wide distribution of comammox Nitrospira in five terrestrial hot springs at temperatures ranging from 36 to 80°C and provide metagenome-assembled genomes of 11 new comammox strains. Interestingly, the identification of dissimilatory nitrate reduction to ammonium (DNRA) in thermophilic comammox Nitrospira lineages suggests that they have versatile ecological functions as both sinks and sources of ammonia, in contrast to the described mesophilic comammox lineages, which lack the DNRA pathway. Furthermore, the in situ expression of key genes associated with nitrogen metabolism, thermal adaptation, and oxidative stress confirmed their ability to survive in the studied hot springs and their contribution to nitrification in these environments. Additionally, the smaller genome size and higher GC content, less polar and more charged amino acids in usage profiles, and the expression of a large number of heat shock proteins compared to mesophilic comammox strains presumably confer tolerance to thermal stress. These novel insights into the occurrence, metabolic activity, and adaptation of comammox Nitrospira in thermal habitats further expand our understanding of the global distribution of comammox Nitrospira and have significant implications for how these unique microorganisms have evolved thermal tolerance strategies.
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Compostos de Amônio , Fontes Termais , Amônia/metabolismo , Ecossistema , Oxirredução , Bactérias/genética , Bactérias/metabolismo , Nitrificação , Compostos de Amônio/metabolismo , Nitratos/metabolismo , Filogenia , Archaea/genéticaRESUMO
Room temperature sodium-sulfur (RT Na-S) batteries are highly competitive as potential energy storage devices. Nevertheless, their actually achieved reversible capacities are far below the theoretical value due to incomplete transformation of polysulfides. Herein, atomically dispersed Fe-N/S active center by regulating the second-shell coordinating environment of Fe single atom is proposed. The Fe-N4 S2 coordination structure with enhanced local electronic concentration around the Fermi level is revealed via synchrotron radiation X-ray absorption spectroscopy (XAS) and theoretical calculations, which can not only significantly promote the transformation kinetics of polysulfides, but induce uniform Na deposition for dendrite-free Na anode. As a result, the obtained S cathode delivers a high initial reversible capacity of 1590â mAh g-1 , nearly the theoretical value. This work opens up a new avenue to facilitate the complete transformation of polysulfides for RT Na-S batteries.
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Ferro , Ferro/química , Elétrons , Modelos Moleculares , Conformação Molecular , Difração de Raios XRESUMO
Spinel bimetallic transition metal oxide anode such as ZnMn2O4, has drawn increasing interest due to attractive bimetal interaction and high theoretical capacity. While it suffers from huge volume expansion and poor ionic/electronic conductivity. Nanosizing and carbon modification can alleviate these issues, while the optimal particle size within host is unclear yet. We here propose an in-situ confinement growth strategy to fabricate pomegranate-structured ZnMn2O4 nanocomposite with calculated optimal particle size in mesoporous carbon host. Theoretical calculations reveal favorable interatomic interactions between the metal atoms. By the synergistic effects of structural merits and bimetal interaction, the optimal ZnMn2O4 composite achieves greatly improved cycling stability (811 mAh g-1 at 0.2 A g-1 after 100 cycles), which can maintain its structural integrity upon cycling. X-ray absorption spectroscopy analysis further confirms delithiated Mn species (Mn2O3 but little MnO). Briefly, this strategy brings new opportunity to ZnMn2O4 anode, which could be adopted to other conversion/alloying-type electrodes.
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The ideal electrolyte for the widely used LiNi0.8Mn0.1Co0.1O2 (NMC811)||graphite lithium-ion batteries is expected to have the capability of supporting higher voltages (≥4.5 volts), fast charging (≤15 minutes), charging/discharging over a wide temperature range (±60 degrees Celsius) without lithium plating, and non-flammability1-4. No existing electrolyte simultaneously meets all these requirements and electrolyte design is hindered by the absence of an effective guiding principle that addresses the relationships between battery performance, solvation structure and solid-electrolyte-interphase chemistry5. Here we report and validate an electrolyte design strategy based on a group of soft solvents that strikes a balance between weak Li+-solvent interactions, sufficient salt dissociation and desired electrochemistry to fulfil all the aforementioned requirements. Remarkably, the 4.5-volt NMC811||graphite coin cells with areal capacities of more than 2.5 milliampere hours per square centimetre retain 75 per cent (54 per cent) of their room-temperature capacity when these cells are charged and discharged at -50 degrees Celsius (-60 degrees Celsius) at a C rate of 0.1C, and the NMC811||graphite pouch cells with lean electrolyte (2.5 grams per ampere hour) achieve stable cycling with an average Coulombic efficiency of more than 99.9 per cent at -30 degrees Celsius. The comprehensive analysis further reveals an impedance matching between the NMC811 cathode and the graphite anode owing to the formation of similar lithium-fluoride-rich interphases, thus effectively avoiding lithium plating at low temperatures. This electrolyte design principle can be extended to other alkali-metal-ion batteries operating under extreme conditions.
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Tryptophan (Trp) metabolism has been implicated in neuroinflammatory and neurodegenerative disorders, but its relationship with neuromyelitis optica spectrum disorder (NMOSD) is unclear. In this pilot study, cerebrospinal fluid (CSF) was prospectively collected from 26 NMOSD patients in relapse and 16 controls with noninflammatory diseases and 6 neurometabolites in the tryptophan metabolic pathway, including 5-hydroxytryptamine (5-HT), kynurenine (KYN), melatonin (MLT), 5-hydroxyindoleacetic acid (5HIAA), 3-hydroxy-o-aminobenzoic acid (3-HAA), and kynurenic acid (KYA), were measured by ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The association of Trp metabolites with NMOSD and its clinical parameters was evaluated. The role of KYN, which is a Trp metabolite involved in the binding of NMOSD-IgG antibody to aquaporin 4 (AQP4), was also evaluated in vitro. CSF KYN was significantly decreased in patients with relapsing NMOSD compared to controls, and CSF KYN was associated with CSF white blood cells in NMOSD. In vitro experiments showed that NMOSD-IgG specifically recognized KYN, which reversed the NMOSD-IgG-induced downregulation of AQP4 expression. Our results show that abnormal Trp metabolism occurs in NMOSD and that KYN might be a potential target for the treatment of AQP4-IgG-positive NMOSD patients.