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BACKGROUND: Cellobiose 2‐epimerase (CE) has received great attention due to its potential applications in the food and pharmaceutical industries. In this study, a novel CE from mesophilic anaerobic halophilic bacterium Iocasia fonsfrigidae strain SP3‐1 (IfCE) was successfully expressed in Escherichia coli and characterized. RESULTS: Unlike other CEs, the purified IfCE shows only epimerization activity toward β‐1,4‐glycosidic linkages of disaccharides, including mannobiose, cellobiose and lactose, but not for monosaccharides, β‐1,4‐glycosidic linkages of trisaccharides and α‐1,4‐glycosidic linkages of disaccharides. Only one epimerization product was obtained from the action of IfCE against mannobiose, cellobiose and lactose. Under optimum conditions, 31.0% of epilactose, a rare and low‐calorie prebiotic sweetener with medicinal and pharmacological properties, was obtained from 10 mg mL−1 lactose. IfCE was highly active against lactose under NaCl concentrations up to 500 mmol L−1, possibly due to the excessive basic (arginine and lysine) and acidic (aspartic and glutamic acids) amino acid residues, which are localized on the surface of the halophilic enzyme structure. These residues may protect the enzyme from Cl− and Na+ ions from the environment, respectively. Under normal conditions, IfCE was able to convert lactose present in fresh goat milk to epilactose with a conversion yield of 31% in 10 min. In addition, IfCE has been investigated as a safe enzyme for human allergen. CONCLUSION: The results suggested that IfCE is a promising candidate to increase the quality and value of milk and dairy products by converting lactose that causes digestive problems in people with lactose intolerance into epilactose. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Chemically cross‐linked hydrogels are synthesized from a set of protected L‐lysine and L‐glutamic acid containing homo and copolypetides. Cross‐linking of the linear copolypeptides is achieved through the incorporation of L‐tryptophan and its reaction with hexamethylene bis(triazolinodione). Upon deprotection, hydrogels with oppositely charged polypeptides of different L‐lysine and L‐glutamic acid composition form pH‐dependent polyion complexes through electrostatic interaction. The obtained networks show distinct pH‐dependent differences in their water swelling and rheological properties. Hydrogels at pH 4 display higher strengths compared to pH 8 and their rheological properties scale with L‐lysine/L‐glutamic acid ratio. At pH 8 results suggests that ionic interactions and presumably secondary structure effects have a significant impact on the hydrogel properties. This is further evident from the influence of the copolypetide structures, random versus block copolypeptides, used in the cross‐linked hydrogel. None of the hydrogel shows any significant cytotoxicity against skin cell lines. [ABSTRACT FROM AUTHOR]

Bacterial toxin‐antitoxin (TA) systems consist of a toxin that inhibits essential cellular processes, such as DNA replication, transcription, translation, or ATP synthesis, and an antitoxin neutralizing their cognate toxin. These systems have roles in programmed cell death, defense against phage, and the formation of persister cells. Here, we characterized the previously identified Staphylococcus aureus TA system, tsaAT, which consists of two putative membrane proteins: TsaT and TsaA. Expression of the TsaT toxin caused cell death and disrupted membrane integrity, whereas TsaA did not show any toxicity and neutralized the toxicity of TsaT. Furthermore, subcellular fractionation analysis demonstrated that both TsaA and TsaT localized to the cytoplasmic membrane of S. aureus expressing either or both 3xFLAG‐tagged TsaA and 3xFLAG‐tagged TsaT. Taken together, these results demonstrate that the TsaAT TA system consists of two membrane proteins, TsaA and TsaT, where TsaT disrupts membrane integrity, ultimately leading to cell death. Although sequence analyses showed that the tsaA and tsaT genes were conserved among Staphylococcus species, amino acid substitutions between TsaT orthologs highlighted the critical role of the 6th residue for its toxicity. Further amino acid substitutions indicated that the glutamic acid residue at position 63 in the TsaA antitoxin and the cluster of five lysine residues in the TsaT toxin are involved in TsaA's neutralization reaction. This study is the first to describe a bacterial TA system wherein both toxin and antitoxin are membrane proteins. These findings contribute to our understanding of S. aureus TA systems and, more generally, give new insight into highly diverse bacterial TA systems. [ABSTRACT FROM AUTHOR]

BACKGROUND: The main edible part of the Lou onion is the pseudostem, which is highly valued for its distinctive flavour. However, harvesting decisions for the pseudostem are often based on size and market price, with little consideration given to flavour. By clarifying the growth of flavour in pseudostems, farmers and consumers may benefit from evidence‐based insights that help optimize harvesting time and maximize flavour quality. RESULTS: This study employed amino acid analysis and gas chromatography–ion migration spectroscopy (GC–IMS) to elucidate the compounds of the pseudostem across different growth phases, and 17 amino acids and 61 volatile substances. Subsequently, analysis revealed that 18 compounds, including arginine (Arg), aspartic acid (Asp), glutamic acid (Glu), valine (Val), (E)‐2‐nonenal, decanal, 2,4‐nonadienal, 2‐octenal, (Z)‐4‐decenal, 2,4‐decadienal benzeneacetaldehyde, linalool, eugenol, (Z)‐6‐nonen‐1‐ol, methyl anthranilate, 2‐acetylpyridine, 3‐sec‐butyl‐2‐methoxypyrazine, and 2,6‐dichlorophenol, were the key compounds in determining the flavour characteristics of the pseudostems, as assessed by taste activity value and relative odour activity value calculations. In addition, correlation analysis, focusing on five amino acids and 38 volatile compounds with variable importance for predictive components scores of >1, identified anisaldehyde, eugenol, (Z)‐6‐nonen‐1‐ol, 2,4‐decadienal, 3‐sec‐butyl‐2‐methoxypyrazine, Arg, Asp, and Val as the key differentiators and contributors to the pseudostems flavour profile. CONCLUSION: During the rapid growth of Lou onions just before the emergence of flower stems, the pseudostem exhibited the most prominent flavour, making this stage most suitable for harvesting compared to the regreening growth stage and the rapid growth period of the aerial bulbs. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Summary: In this study, a new process was proposed to make the yellow tomato puree more sustainable, avoiding any waste during production and including peels and seeds in it. In addition, as raw material tomatoes grown without irrigation and fertilisation procedures were used to increase the sustainability. With respect to a traditional puree, the whole‐fruit yellow tomato puree contained more β‐carotene and polyphenols, exhibiting greater antioxidant capacity, and showed greater consistency due to the high content of pectin in peels. Moreover, a higher content of glutamic acid, responsible for the umami taste, was detected particularly in products from GiaGiù ecotype. Sensory analysis assessed that whole‐fruit yellow tomato puree has good acceptability and consumers preferred it for the texture. In conclusion, the whole‐fruit yellow tomato puree is not only a sustainable product but can be also used as an excellent ingredient in food formulation with antioxidant properties. [ABSTRACT FROM AUTHOR]

The neuronal tricarboxylic acid and glutamate/glutamine (Glu/Gln) cycles play important roles in brain function. These processes can be measured in vivo using dynamic 1H–[13C] MRS during administration of 13C‐labeled glucose. Proton‐observed carbon‐edited (POCE) MRS enhances the signal‐to‐noise ratio (SNR) compared with direct 13C‐MRS. Ultra‐high field further boosts the SNR and increases spectral dispersion; however, even at 7 T, Glu and Gln 1H‐resonances may overlap. Further gain can be obtained with selective POCE (selPOCE). Our aim was to create a setup for indirect dynamic 1H–[13C] MRS in the human brain at 7 T. A home‐built non‐shielded transmit–receive 13C‐birdcage head coil with eight transmit–receive 1H‐dipole antennas was used together with a 32‐channel 1H‐receive array. Electromagnetic simulations were carried out to ensure that acquisitions remained within local and global head SAR limits. POCE‐MRS was performed using slice‐selective excitation with semi‐localization by adiabatic selective refocusing (sLASER) and stimulated echo acquisition mode (STEAM) localization, and selPOCE‐MRS using STEAM. Sequences were tested in a phantom containing non‐enriched Glu and Gln, and in three healthy volunteers during uniformly labeled 13C‐glucose infusions. In one subject the voxel position was alternated between bi‐frontal and bi‐occipital placement within one session. [4‐13C]Glu‐H4 and [4‐13C]Gln‐H4 signals could be separately detected using both STEAM‐POCE and STEAM‐selPOCE in the phantom. In vivo, [4,5‐13C]Glx could be detected using both sLASER‐POCE and STEAM‐POCE, with similar sensitivities, but [4,5‐13C]Glu and [4,5‐13C]Gln signals could not be completely resolved. STEAM‐POCE was alternately performed bi‐frontal and bi‐occipital within a single session without repositioning of the subject, yielding similar results. With STEAM‐selPOCE, [4,5‐13C]Glu and [4,5‐13C]Gln could be clearly separated. We have shown that with our setup indirect dynamic 1H–[13C] MRS at 7 T is feasible in different locations in the brain within one session, and by using STEAM‐selPOCE it is possible to separate Glu from Gln in vivo while obtaining high quality spectra. [ABSTRACT FROM AUTHOR]

Astronomical impacts by small solar system bodies (meteoroids, asteroids, comets, and transitional objects) are considered a mechanism for delivering amino acids and their polymerization to proteins in early Earth conditions. High‐pressure torsion (HPT) is a new methodology to simulate such impacts and clarify the behavior of biomolecules. Herein, two amino acids, crystalline L‐serine and L‐glutamic acid that are detected in meteorites, are processed by HPT and examined by ex situ X‐ray diffraction, Raman spectroscopy, nuclear magnetic resonance, Fourier‐transform infrared spectroscopy, and in situ mechanical shear testing. No polymerization, chemical reactions, or phase transformations are detected after HPT, indicating that the stability and presence of these two amino acids in meteorites are quite reasonable. However, some microstructural and mechanical changes like crystal size reduction to the nanometer level, crystal defect formation, lattice expansion by vacancy formation, and shear strength enhancement to the steady state are found which are similar to the behaviors reported in metals and ceramics after HPT processing. [ABSTRACT FROM AUTHOR]

Cytotoxic neuronal swelling and glutamate excitotoxicity are two hallmarks of ischemic stroke. However, the underlying molecular mechanisms are not well understood. Here, it is reported that SWELL1, the essential subunit of the volume‐regulated anion channel (VRAC), plays a dual role in ischemic injury by promoting neuronal swelling and glutamate excitotoxicity. SWELL1 expression is upregulated in neurons and astrocytes after experimental stroke in mice. The neuronal SWELL1 channel is activated by intracellular hypertonicity, leading to Cl− influx‐dependent cytotoxic neuronal swelling and subsequent cell death. Additionally, the SWELL1 channel in astrocytes mediates pathological glutamate release, indicated by increases in neuronal slow inward current frequency and tonic NMDAR current. Pharmacologically, targeting VRAC with a new inhibitor, an FDA‐approved drug Dicumarol, attenuated cytotoxic neuronal swelling and cell death, reduced astrocytic glutamate release, and provided significant neuroprotection in mice when administered either before or after ischemia. Therefore, these findings uncover the pleiotropic effects of the SWELL1 channel in neurons and astrocytes in the pathogenesis of ischemic stroke and provide proof of concept for therapeutically targeting it in this disease. [ABSTRACT FROM AUTHOR]

Radical S‐adenosyl‐L‐methionine (SAM) enzymes couple the reductive cleavage of SAM to radical‐mediated transformations that have proven to be quite broad in scope. DesII is one such enzyme from the biosynthetic pathway of TDP‐desosamine where it catalyzes a radical‐mediated deamination. Previous studies have suggested that this reaction proceeds via direct elimination of ammonia from an α‐hydroxyalkyl radical or its conjugate base (i.e., a ketyl radical) rather than 1,2‐migration of the amino group to form a carbinolamine radical intermediate. However, without a crystal structure, the active site features responsible for this chemistry have remained largely unknown. The crystallographic studies described herein help to fill this gap by providing a structural description of the DesII active site. Computational analyses based on the solved crystal structure are consistent with direct elimination and indicate that an active site glutamate residue likely serves as a general base to promote deprotonation of the α‐hydroxyalkyl radical intermediate and elimination of the ammonia group. [ABSTRACT FROM AUTHOR]

3‐methyl‐4‐(hetero)arylmethylidene isoxazole‐5(4H)‐one derivatives (4a‐r) derivatives (4a‐r) were synthesized by the multi‐component reactions. The multi‐component reactions (MCRs) of hydroxylamine hydrochloride, ethyl acetoacetate and aromatic/ heteroaromatic aldehyde catalyzed by novel Glutamic acid (Glu) as a biodegradable and eco‐friendly organocatalyst in ethanol on oil bath stirring at 60 °C. The final product homogeneity was examined by various spectroscopic techniques. In this work prepared compounds 4 q and 4 r are novel derivatives. The molecular dynamics of total energy and energy gap was calculated using DFT/B3LYP/6–31G (dp) method. The selected derivatives (4 l–r) screened against in vitro MCF‐7 breast cancer cell line by MTT assay, derivatives 4 l and 4 o displayed very good activity with IC50 of 6.57±2.31, and 21.93±1.34 as compared to doxorubicin of IC50 (3.69±0.17). Molecular docking studies were performed to evaluate interaction of PDB id: 1 M17 with led molecules of MCF‐7. Later, 1 M17 and 4 l underwent 200 ns molecular dynamics and simulation within physiological conditions, the outcomes showed that during the simulation, the ligand stayed in the same form. Further, the selected derivatives drug like computed using swissADME, and derivatives 4 l–r obeyed rule of Lipinski's. Furthermore, selected derivatives tested for electrochemical behavior using cyclic voltammetry, and compound 4 l and 4 q showed strong oxidation and reduction potential, thus these derivatives can present better antioxidant properties. [ABSTRACT FROM AUTHOR]

Xanthurenic acid (XA) raises a growing multidisciplinary interest based upon its oxidizing properties, its ability to complex certain metal ions, and its detoxifier capacity of 3‐hydroxykynurenine (3‐HK), its brain precursor. However, little is still known about the role and mechanisms of action of XA in the central nervous system (CNS). Therefore, many research groups have recently investigated XA and its central functions extensively. The present paper critically reviews and discusses all major data related to XA properties and neuronal activities to contribute to the improvement of the current knowledge on XA's central roles and mechanisms of action. In particular, our data showed the existence of a specific G‐protein‐coupled receptor (GPCR) for XA localized exclusively in brain neurons exhibiting Ca2+‐dependent dendritic release and specific electrophysiological responses. XA properties and central activities suggest a role for this compound in brain intercellular signaling. Indeed, XA stimulates cerebral dopamine (DA) release contrary to its structural analog, kynurenic acid (KYNA). Thus, KYNA/XA ratio could be fundamental in the regulation of brain glutamate and DA release. Cerebral XA may also represent an homeostatic signal between the periphery and several brain regions where XA accumulates easily after peripheral administration. Therefore, XA status in certain psychoses or neurodegenerative diseases seems to be reinforced by its brain‐specific properties in balance with its formation and peripheral inputs. [ABSTRACT FROM AUTHOR]

BACKGROUND: The research about sustainable and alternative plant protein sources has accelerated with the increasing need for protein. Safflower meal has a potential to be used in protein production due to its high protein content. This research aimed to produce an alternative plant‐based protein powder using safflower meal. Both extraction and spray‐drying parameters of safflower protein powder production were optimized using response surface methodology to achieve maximum yield. Moreover, the physicochemical and functional properties of safflower protein were determined and compared with those of commercial protein powders (soy, sunflower, pea, fava bean, and rice). RESULTS: The optimum extraction conditions were found to be 33.06:1 mL−1 g solvent‐to‐meal ratio, pH 11.00, 23.34 °C extraction temperature, and 30.86 min extraction time, which were achieved with a protein yield response of 75.21%. The highest powder yield (51.28%) was recorded for drying conditions of inlet air temperature of 160.11 °C, aspiration rate of 54.17 m3 h−1, and feed flow rate of 16.01 mL min−1. According to the amino acid profile of safflower protein, the glutamic acid content (14 475 mg (100 g)−1) was highest, while the methionine content (96 mg (100 g)−1) was lowest. Moreover, safflower protein can be regarded as a high‐quality protein due to its high essential amino acid ratio (41.55%). The experiments showed that safflower protein had high solubility and good foam and emulsifying properties. CONCLUSION: Safflower protein could be a nutritional and functional protein source for the food industry. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Rhizopus oryzae lipase (ROL) is known to present high selectivity in chemical reactions. However, the poor stability of ROL effectively limits its industrial applications. In this study, several immobilization protocols, such as hydrophobic adsorption, covalent immobilization, multi‐point covalent attachment, ionic adsorption/cross‐linking, and ionic interaction, were applied to improve the stability of ROL. Heterogeneous modification of aspartic and glutamic acid residues on the surface of ROL was carried out by 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC) to introduce new amine groups with lower pKb. The highest immobilization yield of 89% was achieved for octyl‐agarose, producing specific activity of 45 U/mg, which is 15 folds higher than the specific activity of the soluble enzyme. Improved stability of ROL was observed, in particular for those derivatives obtained by multi‐point covalent attachment of ROL on glyoxyl‐agarose (Gx‐ROL) and aminated ROL on glyoxyl‐agarose (Gx‐NH2‐ROL) by retaining 28%–36% of their initial activities after 24 h incubation at 60°C. Immobilization also altered the co‐solvent stability profile of the immobilized derivatives producing biocatalysts with varied co‐solvent stabilities. Furthermore, utilization of the immobilized preparations in fish oil hydrolysis revealed the selective release of cis‐5,8,11,14,17‐eicosapentaenoic acid (EPA) and cis‐4,7,10,13,16,19‐docosahexaenoic acid (DHA) in favor of EPA. The highest EPA/DHA selectivity of 33 was observed for the hydrophobically immobilized ROL on octyl‐sepharose. [ABSTRACT FROM AUTHOR]

Excessive ultraviolet (UV) radiation causes a series of adverse effects on human skin, such as erythema and tanning due to the produce of endogenous melanin of human skin. Inspired by the self‐defense mechanism of human skin to prevent UV radiation damage, we construct a natural and biocompatible Carb@PDA−L sunscreen hydrogel by doping melanin‐like L‐lysine doped polydopamine (PDA−L) to biocompatible poly‐γ‐glutamic acid based hydrogel matrix Carb, which displays good biosafety, efficient UV shielding performance and excellent antioxidative and anti‐inflammatory performance in the application of the skin protection of sun and repair after sunburn. The melanin‐like PDA−L can be synthesized by the oxidative polymerization of dopamine triggered by L‐lysine under alkali‐free condition, which exhibits increase absorption intensity in the UV region and better reactive oxygen species removal performance compared with undoped polydopamine in the perspective of a UV absorber. Meanwhile, PDA−L, as the synthetic analogue of natural melanin, has good biosafety, which can avoid the skin oxidative damage and penetrative toxicity of the conventional sunscreen. [ABSTRACT FROM AUTHOR]

Isoliensinine (ISO), a natural compound, is a bibenzyl isoquinoline alkaloid monomer in lotus seed, which has strong antioxidant and free radical scavenging activities. The oxidative toxicity caused by glutamic acid overdose is one of the important mechanisms of nerve cell injury, and the oxidative toxicity caused by glutamic acid is related to ferroptosis. This study aims to establish a glutamate‐induced injury model of mouse hippocampal neurons HT‐22 cells, and investigate the protective effect of ISO on the neurotoxicity of glutamate‐induced HT‐22 cells. The results showed that ISO inhibited glutamate‐induced ferroptosis of neuronal cells through nuclear factor E2‐related factor 2/glutathione peroxidase 4 (Nrf2/GPX4) signaling pathway. Pretreatment of HT‐22 cells with ISO significantly reduced glutamate‐induced cell death. Ferroptosis inhibitors have the same effect. ISO inhibited the decrease of mitochondrial membrane potential detection and the increase of iron content induced by glutamate, the increase of malondialdehyde and reactive oxygen species in cytoplasm and lipid, and protected the activities of GPx and superoxide dismutase enzymes. In addition, WB showed that glutamic acid could induce the upregulated expression of long‐chain esteryl coA synthase 4 (ACSL4) protein and the downregulated expression of SLC7A11 and GPX4 protein in HT‐22 cells, while ISO could prevent the abnormal expression of these proteins induced by glutamic acid. The nuclear translocation of Nrf2 in HT‐22 cells was increased, and the expression of downstream heme oxygenase‐1 protein was upregulated. In summary, ISO protects HT‐22 cells from glutamate‐induced ferroptosis through a novel mechanism of the Nrf2/GPX4 signaling pathway. [ABSTRACT FROM AUTHOR]

BACKGROUND: Energy‐saving and low‐carbon baking processes, as well as the need to determine the flavor‐forming mechanisms of baked dried tofu, are becoming increasingly necessary. The application of emerging catalytic infrared radiation (CIR) technology in baking of dried tofu is considered of high interest due to the low energy consumption and high baking efficiency compared to traditional baking methods. Hence, this study aimed to investigate the evolution of aroma compounds in baked dried tofu during the CIR baking process and reveal relevant relationships between physical qualities, potential flavor precursors and key volatile compounds. RESULTS: The results showed that the surface color of dried tofu gradually turned an appetizing golden yellow color during the rapid heating process, caused by the uniform infrared radiation from the radiant emitters. Meanwhile, the moisture of dried tofu experienced minimal reduction and the hardness of dried tofu gradually increased with the formation of crust on the surface. In addition, 49 volatile compounds were identified by headspace solid‐phase microextraction–gas chromatography–mass spectrometry and 13 substances – 1‐hexanol, 1‐octen‐3‐ol, 1‐pentanol, heptanal, nonanal, hexanal, (E,E)‐2,4‐decadienal, (E,Z)‐2,4‐decadienal, octanal, (E)‐2‐octenal, (E)‐2‐nonenal, 2‐heptanone and 2‐pentylfuran – were confirmed as key aroma compounds. Moreover, the amino acids aspartic acid, glutamic acid, isoleucine, lysine and arginine, and the fatty acids butyric, caprylic, capric, tridecanoic, stearic, oleic and linolenic were responsible for the unique flavor of CIR‐baked dried tofu. CONCLUSION: Consequently, the findings can provide a scientific basis for manufacturers to achieve precise quality control and large‐scale production of CIR‐baked dried tofu products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Glutamate is one of the most important excitatory neurotransmitters within the mammalian central nervous system. The role of glutamate in regulating neural network signaling transmission through both synaptic and extra‐synaptic paths highlights the importance of the real‐time and continuous monitoring of its concentration and dynamics in living organisms. Progresses in multidisciplinary research have promoted the development of electrochemical glutamate sensors through the co‐design of materials, interfaces, electronic devices, and integrated systems. This review summarizes recent works reporting various electrochemical sensor designs and their applicability as miniaturized neural probes to in vivo sensing within biological environments. We start with an overview of the role and physiological significance of glutamate, the metabolic routes, and its presence in various bodily fluids. Next, we discuss the design principles, commonly employed validation models/protocols, and successful demonstrations of multifunctional, compact, and bio‐integrated devices in animal models. The final section provides an outlook on the development of the next generation glutamate sensors for neuroscience and neuroengineering, with the aim of offering practical guidance for future research. [ABSTRACT FROM AUTHOR]

Lacking strategies to simultaneously address the narrow interlayer spacing, irreversible phase transitions, dissolution and electrical transport issues of vanadium oxides is restricting their application in aqueous zinc‐ion batteries. Herein, to address these challenges concurrently, an organic‐inorganic hybrid cathode is explored, HNaV6O16·4H2O‐Glu (HNVO‐Glu), through a guest material‐mediated NVO synthesis strategy utilizing glutamic acid (Glu) to induce Na substituted by proton and enable crystal transformation of Na2V6O16·3H2O (NVO). Specially, Glu insertion kills three birds with one arrow: i) induces the formation of a structurally stable monoclinic HNaV6O16·4H2O phase by introducing H into the NVO framework, preventing structural phase change and collapse of NVO material; ii) acts as a pillar to expand the interlayer spacing, which improves the Zn2+ diffusion kinetics; moreover, the polar groups on the Glu surface weaken the electrostatic interaction between Zn2+ and the host materials, further enhancing the zinc‐ionic transport rate; iii) enhances the electrical conductivity of HNVO by converting the p‐type semiconductor into the n‐type semiconductor structure. Consequently, the HNVO‐Glu exhibits a high specific capacity (354.6 mAh g−1 at 1 A g−1), excellent Zn2+ diffusion capability (10−9 to 10−7 cm2 s−1) and outstanding cycling stability with a capacity retention of 87.2% after 12 000 cycles at 10 A g−1. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is a critical condition with a wide range of triggers that cause heavy burden on public health. Despite its high incidence and mortality, the treatment of AKI still highly relies on hemodialysis, which is costly and usually accompanied by severe complications. Therefore, development of new therapeutic targets and methods for AKI is urgently needed. Herein, a ferroptosis‐targeting strategy for AKI treatment by rationally designed ferroptosis‐inhibitive polypeptide‐based polymersomes (polypeptosomes, FIPs) is proposed. Such FIPs are self‐assembled from poly(glutamic acid)‐block‐poly(methionine‐stat‐tyrosine) [PGA9‐b‐P(Met8‐stat‐PTyr13)]. The ferroptosis‐inhibition function of the FIPs arises from the rationally‐selected amino acid composition: P(Met‐stat‐Tyr) endows the FIPs with a high scavenging efficiency of over 90% toward different reactive oxygen species (ROS); while the glutamate and tyrosine residues, as well as the amide groups, can bind iron ions, thus blocking iron overload and lipid peroxide in cells. In vivo experiments confirm that the FIPs can effectively alleviate oxidative stress, inhibit ferroptosis, and restore kidney functions. Transcriptome sequencing further reveals the therapeutic mechanisms of FIPs. Overall, such polypeptosomes capable of blocking multiple pathways of ferroptosis open a new avenue for AKI treatment and provide fresh insights into the development of generalized therapies for inflammation. [ABSTRACT FROM AUTHOR]

In this work, we present simulations of the optical rotation (OR) for five molecular crystals at density functional theory level with periodic boundary conditions (DFT‐PBC). Calculations are compared with experimental measurements and show semi‐quantitative agreement with experimental data for three of the crystals: tartatic acid, benzil, and pentaerythritol. For the other two crystals, aspartic acid and glutamic acid, the calculated data are in qualitative agreement with, but two orders of magnitude smaller than, the experimental data. We provide some arguments that support the theoretical predictions and suggest that the experiments should be revisited. We also find that the position of H centers provided in experimental X‐ray data is not sufficiently reliable for simulating OR, and better results are obtained when H atoms are allowed to relax while keeping heavier elements fixed at the experimental positions. Comparison with molecular cluster calculations with a better functional and a larger basis set indicate that the role of intermolecular interactions (reproduced with the PBC technique) is as or more important than the choice of model chemistry. Despite the current limitations in the level of theory that can be employed, these simulations provide a promising avenue to investigate the effect of intermolecular interactions on this sensitive electronic property of molecules and materials. [ABSTRACT FROM AUTHOR]

BACKGROUND: One of the greatest challenges in using Lactobacillus acidophilus as a probiotic is acid stress. The current research aimed to identify substances that help L. acidophilus resist acid stress; this was achieved through assessing its nutrient consumption patterns under various pH conditions. RESULTS: The consumption rates of alanine, uracil, adenine, guanine, niacin, and manganese were consistently higher than 60% for L. acidophilus LA‐5 cultured at pH 5.8, 4.9, and 4.4. The consumption rates of glutamic acid + glutamine and thiamine increased with decreasing pH and were higher than 60% at pH 4.9 and 4.4. The viable counts of L. acidophilus LA‐5 were significantly increased under the corresponding acidic stress conditions (pH 4.9 and 4.4) through the appropriate addition of either alanine (3.37 and 2.81 mmol L−1), glutamic acid + glutamine (4.77 mmol L−1), guanine (0.13 and 0.17 mmol L−1), niacin (0.02 mmol L−1), thiamine (0.009 mmol L−1), or manganese (0.73 and 0.64 mmol L−1) (P < 0.05). The viable counts of L. acidophilus LA‐5 cultured in a medium supplemented with combined nutritional factors was 1.02–1.03‐fold of the counts observed in control medium under all acid conditions (P < 0.05). CONCLUSION: Alanine, glutamic acid + glutamine, guanine, niacin, thiamine, and manganese can improve the growth of L. acidophilus LA‐5 in an acidic environment in the present study. The results will contribute to optimizing strategies to enhance the acid resistance of L. acidophilus and expand its application in the fermentation industry. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Extracellular proteases are a class of public good that support growth of Bacillus subtilis when nutrients are in a polymeric form. Bacillus subtilis biofilm matrix molecules are another class of public good that are needed for biofilm formation and are prone to exploitation. In this study, we investigated the role of extracellular proteases in B. subtilis biofilm formation and explored interactions between different public good producer strains across various conditions. We confirmed that extracellular proteases support biofilm formation even when glutamic acid provides a freely available nitrogen source. Removal of AprE from the NCIB 3610 secretome adversely affects colony biofilm architecture, while sole induction of WprA activity into an otherwise extracellular protease‐free strain is sufficient to promote wrinkle development within the colony biofilm. We found that changing the nutrient source used to support growth affected B. subtilis biofilm structure, hydrophobicity and architecture. We propose that the different phenotypes observed may be due to increased protease dependency for growth when a polymorphic protein presents the sole nitrogen source. We however cannot exclude that the phenotypic changes are due to alternative matrix molecules being made. Co‐culture of biofilm matrix and extracellular protease mutants can rescue biofilm structure, yet reliance on extracellular proteases for growth influences population coexistence dynamics. Our findings highlight the intricate interplay between these two classes of public goods, providing insights into microbial social dynamics during biofilm formation across different ecological niches. [ABSTRACT FROM AUTHOR]

Killer whales (Orcinus orca) occur seasonally in the eastern Canadian Arctic (ECA), where their range expansion associated with declining sea ice have raised questions about the impacts of increasing killer whale predation pressure on Arctic‐endemic prey.We assessed diet and distribution of ECA killer whales using bulk and compound‐specific stable isotope analysis (CSIA) of amino acids (AA) of 54 skin biopsies collected from 2009 to 2020 around Baffin Island, Canada.Bulk ECA killer whale skin δ15N and δ13C values did not overlap with potential Arctic prey after adjustment for trophic discrimination, and instead reflected foraging history in the North Atlantic prior to their arrival in the ECA. Adjusted killer whale stable isotope (SI) values primarily overlapped with several species of North Atlantic baleen whales or tuna. Amino acid (AA)‐specific δ15N values indicated the ECA killer whales fed primarily on marine mammals, having similar glutamic acid δ15N–phenylalanine δ15N (δ15NGlx‐Phe) and threonine δ15N (δ15NThr) as mammal‐eating killer whales from the eastern North Pacific (ENP) that served as a comparative framework. However, one ECA whale grouped with the fish‐eating ENP ecotype based δ15NThr.Distinctive essential AA δ13C of ECA killer whale groups, along with bulk SI similarity to killer whales from different regions of the North Atlantic, indicates different populations converge in Arctic waters from a broad source area. Generalist diet and long‐distance dispersal capacity favour range expansions, and integration of these insights will be critical for assessing ecological impacts of increasing killer whale predation pressure on Arctic‐endemic species. [ABSTRACT FROM AUTHOR]

Melanin‐concentrating hormone (MCH) neurons can co‐express several neuropeptides or neurotransmitters and send widespread projections throughout the brain. Notably, there is a dense cluster of nerve terminals from MCH neurons in the lateral septum (LS) that innervate LS cells by glutamate release. The LS is also a key region integrating stress‐ and anxiety‐like behaviours, which are also emerging roles of MCH neurons. However, it is not known if or where the MCH peptide acts within the LS. We analysed the projections from MCH neurons in male and female mice anteroposteriorly throughout the LS and found spatial overlap between the distribution pattern of MCH‐immunoreactive (MCH‐ir) fibres with MCH receptor Mchr1 mRNA hybridization or MCHR1‐ir cells. This overlap was most prominent along the ventral and lateral border of the rostral part of the LS (LSr). Most MCHR1‐labelled LS neurons lay adjacent to passing MCH‐ir fibres, but some MCH‐ir varicosities directly contacted the soma or cilium of MCHR1‐labelled LS neurons. We thus performed whole‐cell patch‐clamp recordings from MCHR1‐rich LSr regions to determine if and how LS cells respond to MCH. Bath application of MCH to acute brain slices activated a bicuculline‐sensitive chloride current that directly hyperpolarized LS cells. This MCH‐mediated hyperpolarization was blocked by calphostin C, which suggested that the inhibitory actions of MCH were mediated by protein kinase C‐dependent activation of GABAA receptors. Taken together, these findings define potential hotspots within the LS that may elucidate the contributions of MCH to stress‐ or anxiety‐related feeding behaviours. Key points: Melanin‐concentrating hormone (MCH) neurons have dense nerve terminals within the lateral septum (LS), a key region underlying stress‐ and anxiety‐like behaviours that are emerging roles of the MCH system, but the function of MCH in the LS is not known.We found spatial overlap between MCH‐immunoreactive fibres, Mchr1 mRNA, and MCHR1 protein expression along the lateral border of the LS.Within MCHR1‐rich regions, MCH directly inhibited LS cells by increasing chloride conductance via GABAA receptor activation in a protein kinase C‐dependent manner.Electrophysiological MCH effects in brain slices have been elusive, and few studies have described the mechanisms of MCH action. Our findings demonstrated, to our knowledge, the first description of MCHR1 Gq‐coupling in brain slices, which was previously predicted in cell or primary culture models only. Together, these findings defined hotspots and mechanistic underpinnings for MCH effects such as in feeding and anxiety‐related behaviours. [ABSTRACT FROM AUTHOR]

SUMMARY: Heat stress poses a significant threat to maize, especially when combined with drought. Recent research highlights the potential of water replenishment to ameliorate grain weight loss. However, the mitigating mechanisms of heat in drought stress, especially during the crucial early grain‐filling stage, remain poorly understood. We investigated the mechanism for mitigating heat in drought stress by water replenishment from the 12th to the 32nd days after silking in a controlled greenhouse experiment (Exp. I) and field trial (Exp. II). A significant reduction in grain weight was observed in heat stress compared to normal conditions. When water replenishment was applied to increase soil water content (SWC) under heat stress, the grain yield exhibited a notable increase ranging from 28.4 to 76.9%. XY335 variety was used for transcriptome sequencing to analyze starch biosynthesis and amino acid metabolisms in Exp. I. With water replenishment, the transcripts of genes responsible for trehalose 6‐phosphate phosphates (TPP), alpha‐trehalase (TRE), ADP‐glcpyrophosphorylase, and starch synthase activity were stimulated. Additionally, the expression of genes encoding TPP and TRE contributed to an enhanced conversion of trehalose to glucose. This led to the conversion of sucrose from glucose‐1‐phosphate to ADP‐glucose and ADP‐glucose to amylopectin, ultimately increasing starch production by 45.1%. Water replenishment to boost SWC during heat stress also elevated the levels of essential amino acids in maize, including arginine, serine, tyrosine, leucine, glutamic acid, and methionine, providing valuable support to maize plants in adversity. Field trials further validated the positive impact of water replenishment on SWC, resulting in a notable increase in grain yield ranging from 7.1 to 9.2%. This study highlights the vital importance of adapting to abiotic stress and underscores the necessity of developing strategies to counteract its adverse effects on crop yield. [ABSTRACT FROM AUTHOR]

A new automated radiosynthesis of [11C]2‐(2,6‐difluoro‐4‐((2‐(N‐methylphenylsulfonamido)ethyl)thio)phenoxy)acetamide ([11C]K2), a radiopharmaceutical for the glutamate α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionic acid (AMPA) receptor, is reported. Although manual syntheses have been described, these are unsuitable for routine production of larger batches of [11C]K2 for (pre)clinical PET imaging applications. To meet demands for the imaging agent from our functional neuroimaging collaborators, herein, we report a current good manufacturing practice (cGMP)‐compliant synthesis of [11C]K2 using a commercial synthesis module. The new synthesis is fully automated and has been validated for clinical use. The total synthesis time is 33 min from end of bombardment, and the production method provides 2.66 ± 0.3 GBq (71.9 ± 8.6 mCi) of [11C]K2 in 97.7 ± 0.5% radiochemical purity and 754.1 ± 231.5 TBq/mmol (20,382.7 ± 6256.1 Ci/mmol) molar activity (n = 3). Batches passed all requisite quality control testing confirming suitability for clinical use. [ABSTRACT FROM AUTHOR]

Summary: To investigate the mechanism of Penicillium inoculation on the flavour improvement of Jinhua ham, the microbial succession, free amino acid contents, volatile compound evolutions, sensory attributes and the relationship between key volatiles and sensory properties were investigated during the processing of Jinhua ham with P. aethiopicum (PA) or P. chrysogenum (PC) inoculation. The total counts of fungal communities in CK, PA and PC groups significantly increased from 2.74 log CFU*g−1 of raw ham to 5.18, 5.39 and 5.50 log CFU*g−1 from day 0 to day 28, and then decreased by 2.06, 1.94 and 1.86 log CFU*g−1 from day 28 to the final products (P < 0.001). The total contents of free amino acids significantly increased from 1584.22 mg/100 g of CK to 2117.20 mg/100 g of PA and 2174.05 mg/100 g of PC (P < 0.01); the contents of alanine, glutamic acid, lysine, valine, leucine and phenylalanine in PC were significantly higher than those of CK and PA (P < 0.05). Sensory scores of meaty aroma, nutty aroma and overall acceptance showed the largest values in PC among three groups. GC–MS results indicated that aromatic aldehydes and pyrazines in PC showed the largest increase, compared with CK and PA groups. PLS‐DA and correlation analysis demonstrated that benzaldehyde, benzeneacetaldehyde and 2,5‐dimethyl pyrazine contributed to the improvement of aroma attributes of Jinhua ham with Penicillium inoculation. The KEGG analysis further revealed that the metabolism of valine and phenylalanine was mainly involved in developing aromatic aldehydes and pyrazines of Jinhua ham with Penicillium inoculation. These results indicated that the inoculation of Penicillium could enhance the flavour quality of Jinhua ham. [ABSTRACT FROM AUTHOR]

Summary: Shrimp undergo rapid deterioration after death, primarily due to enzyme activity and microbial growth, with freezing serving as its primary preservation method. In this study, shrimp underwent both conventional freezing (CF) and magnetic field‐assisted freezing (MF), and the shrimp meat's metabolites were scrutinised via metabonomic analysis techniques. The results demonstrate that MF treatment effectively preserved umami components like glutamic acid (log2(FC) = 0.37) and inosinic acid (1.02) while inhibiting the accumulation of spoilage‐related metabolites such as inosine (HxR) (−2.51), hypoxanthine (Hx) (−1.43) and uric acid (UA) (−1.24). Moreover, specific compounds, including 3‐methylhistidine, 1,6‐bisphosphate, phosphatidylcholine (PC), phosphatidylethanolamine (PE), HxR, Hx and UA were recognised as potential biomarkers throughout the freezing process. This research offers crucial insights into the intricate molecular mechanisms behind magnetic field‐assisted freezing. [ABSTRACT FROM AUTHOR]

Reducing the dietary crude protein (CP) could effectively reduce pressure on protein ingredient supplies. However, few data have been reported about the extent to which CP can be reduced and whether limiting the use of soybean meal leads to electrolyte imbalance. In this experiment, using the low protein (LP) diet [2% lower than NRC (2012)], seventy‐two piglets (35 days old) were randomly divided into 2 groups with 6 replicates of 6 piglets each: CON group (CP = 18.5%) and LP group (CP = 16.5%), to investigate the effect of the LP diet on electrolyte balance, acid‐base balance, intestinal structure and amino acid transport in piglets. The results revealed that the LP diet decreased the average daily gain and dietary CP digestibility, and damaged the villi structure of the small intestine. Compared with the CON diet, the potassium content decreased and the chlorine content increased in the LP diet, and similar trends were shown in piglet serum. The arterial pH, pCO2, HCO3−, and base excess of piglets in the LP group were lower than those in the CON group, while pO2 was higher than those in the CON group. Interestingly, the LP diet significantly increased the lysine content in piglet serum and significantly decreased the levels of arginine, leucine, and glutamic acid. Furthermore, the LP diet significantly affected the expression of some amino acid transport vectors (B0AT1, EAAC1, and y+LAT1). In summary, these findings suggested that the LP diet leads to acid‐base imbalance, amino acid transport disorder and amino acids imbalance in piglets, and the dietary electrolyte may be a key factor in the impact of the LP diet on piglet growth performance and intestinal health. [ABSTRACT FROM AUTHOR]

Green surfactants produced from peptides and their derivatives have excellent surface chemistry and application properties. A mild, biocompatible, and rapidly biodegradable green surfactant, potassium N‐lauroyl wheat peptide (PLW), was synthesized by an acylation method in the aqueous phase with lauryl chloride and wheat oligopeptide as starting materials. Furthermore, the isoelectric point, equilibrium surface tension, dynamic surface tension, micellar aggregation behavior, foaming, and irritating properties of PLW were studied. Wheat oligopeptides were discovered to have the greatest glutamic acid content, accounting for 30.92% of the overall amino acid composition. The findings revealed that the protonation and ionization behavior of PLW was pH dependent. At pH 8.5, water's surface tension was lowered to 32.1 mN/m−1. At high concentrations and pH, PLW formed large aggregates in solution, causing the adsorption behavior of PLW molecules to shift from diffusion‐controlled adsorption to mixed kinetic adsorption, with PLW exhibiting great surface activity. Furthermore, PLW has good foaming properties and is non‐irritating. As a result, PLW is predicted to become widely employed in the field of household chemicals. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is an increasingly important public health concern due to the increasing proportion of older individuals within the general population. The impairment of processes responsible for adequate brain energy supply primarily determines the early features of the aging process. Restricting brain energy supply results in brain hypometabolism prior to clinical symptoms and is anatomically and functionally associated with cognitive impairment. The present study investigated changes in metabolic profiles induced by intracerebroventricular‐streptozotocin (ICV‐STZ) in an AD‐like animal model. To this end, male Wistar rats received a single injection of STZ (3 mg·kg−1) by ICV (2.5 μL into each ventricle for 5 min on each side). In the second week after receiving ICV‐STZ, rats were tested for cognitive performance using the Morris Water Maze test and subsequently prepared for positron emission tomography (PET) to confirm AD‐like symptoms. Tandem Mass Spectrometry (MS/MS) analysis was used to detect amino acid changes in cerebrospinal fluid (CFS) samples. Our metabolomics study revealed a reduction in the concentrations of various amino acids (alanine, arginine, aspartic acid, glutamic acid, glycine, isoleucine, methionine, phenylalanine, proline, serine, threonine, tryptophane, tyrosine, and valine) in CSF of ICV‐STZ‐treated animals as compared to controls rats. The results of the current study indicate amino acid levels could potentially be considered targets of nutritional and/or pharmacological interventions to interfere with AD progression. [ABSTRACT FROM AUTHOR]

Several studies have suggested that atypical social processing in neurodevelopmental conditions (e.g. autism) is associated with differences in excitation and inhibition, through changes in the levels of glutamate and gamma‐aminobutyric acid (GABA). While associations between baseline metabolite levels and behaviours can be insightful, assessing the neurometabolic response of GABA and glutamate during social processing may explain altered neurochemical function in more depth. Thus far, there have been no attempts to determine whether changes in metabolite levels are detectable using functional MRS (fMRS) during social processing in a control population. We performed Mescher–Garwood point resolved spectroscopy edited fMRS to measure the dynamic response of GABA and glutamate in the superior temporal sulcus (STS) and visual cortex (V1) while viewing social stimuli, using a design that allows for analysis in both block and event‐related approaches. Sliding window analyses were used to investigate GABA and glutamate dynamics at higher temporal resolution. The changes of GABA and glutamate levels with social stimulus were largely non‐significant. A small decrease in GABA levels was observed during social stimulus presentation in V1, but no change was observed in STS. Conversely, non‐social stimulus elicited changes in both GABA and glutamate levels in both regions. Our findings suggest that the current experimental design primarily captures effects of visual stimulation, not social processing. Here, we discuss the feasibility of using fMRS analysis approaches to assess changes in metabolite response. [ABSTRACT FROM AUTHOR]

The impact of glycine and glutamate, as components of glutathione (GSH) precursors, was studied as a factor in determining the growth rate of weaning pigs, their digestion of nutrient supplements and their blood concentration levels. There were 180 crossbred weaning pigs with an average body weight (BW) of 7.94 ± 1.53 kg (five pigs per pen [two barrows and three gilts]; nine pens per treatment) that were randomly assigned to one of four diets. We used a basal diet as the control, TRT1 as the treatment with 0.10% precursor of GSH, TRT2 as the treatment with 0.20% precursor of GSH and TRT3 as the treatment with 0.30% precursor of GSH. The BW of weaning pigs exhibited a linear increase on days 7 (p < 0.001), 21 (p < 0.001) and 42 (p < 0.009) following the supplementation with the GSH precursor. Supplementation with GSH precursor led to a consistent and gradual increase in average daily gain (ADG) on days 8–21, 22–42 and overall, as indicated by a significant linear trend (p < 0.05). G: F was linearly increased (p < 0.05) on days 22–42 and overall with the increment in the precursor of GSH supplementation. However, GSH precursor supplementation did not have any impact on nutrient digestibility and blood profile in the treatment group. In summary, the administration of GSH precursor improved BW, ADG and G: F ratio while not affecting nutrient digestibility or blood profile. [ABSTRACT FROM AUTHOR]

Background and Purpose: To deepen our knowledge of the role of complement in synaptic impairment in experimental autoimmune encephalomyelitis (EAE) mice, we investigated the distribution of C1q and C3 proteins and the role of complement as a promoter of glutamate release in purified nerve endings (synaptosomes) and astrocytic processes (gliosomes) isolated from the cortex of EAE mice at the acute stage of the disease (21 ± 1 day post‐immunization). Experimental Approach: EAE cortical synaptosomes and gliosomes were analysed for glutamate release efficiency (measured as release of preloaded [3H]D‐aspartate ([3H]D‐ASP)), C1q and C3 protein density, and for viability and ongoing apoptosis. Key Results: In healthy mice, complement releases [3H]D‐ASP from gliosomes more efficiently than from synaptosomes. The releasing activity occurs in a dilution‐dependent manner and involves the reversal of the excitatory amino acid transporters (EAATs). In EAE mice, the complement‐induced releasing activity is significantly reduced in cortical synaptosomes but amplified in cortical gliosomes. These adaptations are paralleled by decreased density of the EAAT2 protein in synaptosomes and increased EAAT1 staining in gliosomes. Concomitantly, PSD95, GFAP, and CD11b, but not SNAP25, proteins are overexpressed in the cortex of the EAE mice. Similarly, C1q and C3 protein immunostaining is increased in EAE cortical synaptosomes and gliosomes, although signs of ongoing apoptosis or altered viability are not detectable. Conclusion and Implications: Our results unveil a new noncanonical role of complement in the CNS of EAE mice relevant to disease progression and central synaptopathy that suggests new therapeutic targets for the management of MS. [ABSTRACT FROM AUTHOR]

1,8‐Diazabicyclo[5.4.0]undec‐7‐ene (DBU) catalyzed Michael addition reactions between α,β‐unsaturated esters and benzophenone‐imines of glycine esters have been realized in THF at room temperature by using LiBr as an additive, effectively enabling the glutamation of phenols, thiophenols, secondary amines and imides. 3‐Substituted glutamic acid esters were obtained in excellent yields and diastereoselectivities (up to quantitative yield and >20 : 1 dr). These glutamic acid esters were readily converted into their corresponding pyroglutamic acid esters in high yields through acidic hydrolysis followed by lactamization. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The structural and surface properties of nanomedicines play an important role in determining their biological fate. Surface chemistry of nanomedicines is one of the key parameters, where researchers used various strategies such as PEGylation to avoid the undesired clearance of nanoparticles (NPs) for enhanced targeting effect. Nevertheless, the fine‐tuning of surface chemistry through polymer functionalization remains largely unexplored. In this concise report, we find that the incorporation of only 10 mol% valine residues into the surface‐anchored poly(L‐glutamic acid) significantly lowered the macrophage uptake of NPs. The introduction of other hydrophobic amino acid residues, however, increased the NPs internalization instead. The chirality and the side‐chain structure of valine played an important role in the unexpected uptake behavior. We believe this work highlights the impact of slight changes of the surface‐anchored polymer structure on the behavior of NPs, drawing people's attention to the careful design of surface chemistry to optimize the nanomedicine design. [ABSTRACT FROM AUTHOR]

The commercial production of multifunctional, biocompatible, and biodegradable biopolymers such as poly‐γ‐glutamic acid via microbial fermentation requires the development of simple and cheap methods for mass production. This study optimized the poly‐γ‐glutamic acid production of Bacillus licheniformis ATCC 9945a in several steps. At first, the most critical components of the culture medium, including l‐glutamic acid, citric acid, and glycerol, were selected by screening nine factors through the Plackett–Burman experimental design and then were optimized using the response surface method and the central composite design algorithm. Under optimal conditions, the production of poly‐γ‐glutamic acid increased by more than 4.2 times from 11.2 to 47.2 g/L. This is one of the highest production rates of this strain in submerged batch fermentation reported so far using the optimized medium compared to the conventional base medium. A novel and efficient sudden pulse feeding strategy (achieved by a novel one‐factorial statistical technique) of l‐glutamic acid to the optimized medium increased biopolymer production from 47.2 to 66.1 g/L, the highest value reported in published literature with this strain. This simple, reproducible, and cheap fermentation process can considerably enhance the commercial applications of the poly‐γ‐glutamic acid synthesized by B. licheniformis ATCC 9945a. [ABSTRACT FROM AUTHOR]

Ultrasound‐generated antigens combined with TLR7/8 agonists as adjuvants have demonstrated significant anti‐tumor efficacy as an in‐situ vaccine. However, the use of TLR7/8 agonists can cause severe inflammatory responses. In this study, we present a novel tumor‐targeting nano‐adjuvant termed aPDL1‐PLG/R848 NPs, which are composed of aPDL1 antibody, Fc‐III‐4C peptide linker (Fc‐linker) and poly(L‐glutamic acid)‐grafted‐R848. Under ultrasound irradiation, antigen‐presenting cells activate immune mechanisms in vivo under dual stimulation of in situ antigens and immune adjuvants. The strategy inhibits primary tumor growth and induces a strong antigen‐specific immune memory effect to prevent tumor recurrence in vivo. This work offers a safe and potent platform for an in situ cancer vaccine based on ultrasound therapy. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The structural and surface properties of nanomedicines play an important role in determining their biological fate. Surface chemistry of nanomedicines is one of the key parameters, where researchers used various strategies such as PEGylation to avoid the undesired clearance of nanoparticles (NPs) for enhanced targeting effect. Nevertheless, the fine‐tuning of surface chemistry through polymer functionalization remains largely unexplored. In this concise report, we find that the incorporation of only 10 mol% valine residues into the surface‐anchored poly(L‐glutamic acid) significantly lowered the macrophage uptake of NPs. The introduction of other hydrophobic amino acid residues, however, increased the NPs internalization instead. The chirality and the side‐chain structure of valine played an important role in the unexpected uptake behavior. We believe this work highlights the impact of slight changes of the surface‐anchored polymer structure on the behavior of NPs, drawing people's attention to the careful design of surface chemistry to optimize the nanomedicine design. [ABSTRACT FROM AUTHOR]

Amino acids play important roles in stress resistance, plant growth, development, and quality, with roots serving as the primary organs for drought response. We conducted biochemical and multi‐omics analyses to investigate the metabolic processes of root amino acids in drought‐resistant (HN44) and drought‐sensitive (HN65) soybean (Glycine max) varieties. Our analysis revealed an increase in total amino acid content in both varieties, with phenylalanine, proline, and methionine accumulating in both. Additionally, several amino acids exhibited significant decreases in HN65 but slight increases in HN44. Multi‐omics association analysis identified 13 amino acid‐related pathways. We thoroughly examined the changes in genes and metabolites involved in various amino acid metabolism/synthesis and determined core genes and metabolites through correlation networks. The phenylalanine, tyrosine, and tryptophan metabolic pathways and proline, glutamic acid and sulfur‐containing amino acid pathways were particularly important for drought resistance. Some candidate genes, such as ProDH and P4HA family genes, and metabolites, such as O‐acetyl‐L‐serine, directly affected up‐ and downstream metabolism to induce drought resistance. This study provided a basis for soybean drought resistance breeding. [ABSTRACT FROM AUTHOR]

The human gut hosts numerous ecological niches for microbe–microbe and host–microbe interactions. Gut lactate homeostasis in humans is crucial and relies on various bacteria. Veillonella spp., gut lactate‐utilizing bacteria, and lactate‐producing bacteria were frequently co‐isolated. A recent clinical trial has revealed that lactate‐producing bacteria in humans cross‐feed lactate to Veillonella spp.; however, their interspecies interaction mechanisms remain unclear. Veillonella dispar, an obligate anaerobe commonly found in the human gut and oral cavity, ferments lactate into acetate and propionate. In our study, we investigated the interaction between V. dispar ATCC 17748T and three representative phylogenetically distant strains of lactic acid bacteria, Lactobacillus acidophilus ATCC 4356T, Lacticaseibacillus paracasei subsp. paracasei ATCC 27216T, and Lactiplantibacillus plantarum ATCC 10241. Bacterial growth, viability, metabolism and gene level adaptations during bacterial interaction were examined. V. dispar exhibited the highest degree of mutualism with L. acidophilus. During co‐culture of V. dispar with L. acidophilus, both bacteria exhibited enhanced growth and increased viability. V. dispar demonstrated an upregulation of amino acid biosynthesis pathways and the aspartate catabolic pathway. L. acidophilus also showed a considerable number of upregulated genes related to growth and lactate fermentation. Our results support that V. dispar is able to enhance the fermentative capability of L. acidophilus by presumably consuming the produced lactate, and that L. acidophilus cross‐feed not only lactate, but also glutamate, to V. dispar during co‐culture. The cross‐fed glutamate enters the central carbon metabolism in V. dispar. These findings highlight an intricate metabolic relationship characterized by cross‐feeding of lactate and glutamate in parallel with considerable gene regulation within both L. acidophilus (lactate‐producing) and V. dispar (lactate‐utilizing). The mechanisms of mutualistic interactions between a traditional probiotic bacterium and a potential next‐generation probiotic bacterium were elucidated in the production of short‐chain fatty acids. [ABSTRACT FROM AUTHOR]

Glutamate recycling between neurons and astrocytes is essential to maintain neurotransmitter homeostasis. Disturbances in glutamate homeostasis, resulting in excitotoxicity and neuronal death, have been described as a potential mechanism in Alzheimer's disease (AD) pathophysiology. However, glutamate neurotransmitter metabolism in different human brain cells, particularly astrocytes, has been poorly investigated at the early stages of AD. We sought to investigate glucose and glutamate metabolism in AD by employing human induced pluripotent stem cell (hiPSC)-derived astrocytes and neurons carrying mutations in the amyloid precursor protein (APP) or presenilin-1 (PSEN-1) gene as found in familial types of AD (fAD). Methods such as livecell bioenergetics and metabolic mapping using [13C]-enriched substrates were used to examine metabolism in the early stages of AD. Our results revealed greater glycolysis and glucose oxidative metabolism in astrocytes and neurons with APP or PSEN-1 mutations, accompanied by an elevated glutamate synthesis compared to control WT cells. Astrocytes with APP or PSEN-1 mutations exhibited reduced expression of the excitatory amino acid transporter 2 (EAAT2), and glutamine uptake increased in mutated neurons, with enhanced glutamate release specifically in neurons with a PSEN-1 mutation. These results demonstrate a hypermetabolic phenotype in astrocytes with fAD mutations possibly linked to toxic glutamate accumulation. Our findings further identify metabolic imbalances that may occur in the early phases of AD pathophysiology. [ABSTRACT FROM AUTHOR]

Ca2+/calmodulin-dependent protein kinase II alpha (CaMKIIα) is a key regulator of neuronal signaling and synaptic plasticity. Synaptic activity and neurotransmitter homeostasis are closely coupled to the energy metabolism of both neurons and astrocytes. However, whether CaMKIIα function is implicated in brain energy and neurotransmitter metabolism remains unclear. Here, we explored the metabolic consequences of CaMKIIα deletion in the cerebral cortex using a genetic CaMKIIα knockout (KO) mouse. Energy and neurotransmitter metabolism was functionally investigated in acutely isolated cerebral cortical slices using stable 13C isotope tracing, whereas the metabolic function of synaptosomes was assessed by the rates of glycolytic activity and mitochondrial respiration. The oxidative metabolism of [U-13C] glucose was extensively reduced in cerebral cortical slices of the CaMKIIα KO mice. In contrast, metabolism of [1,2-13C]acetate, primarily reflecting astrocyte metabolism, was unaffected. Cellular uptake, and subsequent metabolism, of [U-13C]glutamate was decreased in cerebral cortical slices of CaMKIIα KO mice, whereas uptake and metabolism of [U-13C]GABA were unaffected, suggesting selective metabolic impairments of the excitatory system. Synaptic metabolic function was maintained during resting conditions in isolated synaptosomes from CaMKIIα KO mice, but both the glycolytic and mitochondrial capacities became insufficient when the synaptosomes were metabolically challenged. Collectively, this study shows that global deletion of CaMKIIα significantly impairs cellular energy and neurotransmitter metabolism, particularly of neurons, suggesting a metabolic role of CaMKIIα signaling in the brain. [ABSTRACT FROM AUTHOR]

Continuous cultivation of faba beans often results in a high occurrence of Fusarium wilt. Nevertheless, this issue can be successfully managed through wheat‐faba bean intercropping. Our objective is to elucidate the function of non‐host wheat in combating faba bean Fusarium wilt. We assessed the impact of wheat on the development of faba bean Fusarium wilt through field and pot experiments, and examined and identified the compounds in the root exudates of wheat. The influence of wheat root exudates on Fusarium commun mycelial growth and spore multiplication was investigated through indoor culture experiments. Wheat‐faba bean intercropping significantly reduced the occurrence of Fusarium wilt in field trials. Root separation experiments in pots indicated that wheat root exudates might play a vital role in this outcome. The exogenous addition of wheat root exudates to faba bean grown alone notably decreased the occurrence and severity of Fusarium wilt. Furthermore, the exogenous addition of wheat root exudates effectively hindered the growth and reproduction of Fusarium commun's mycelium. And, wheat root exudates contained six compounds with relatively high concentrations, including salicylic acid, p‐hydroxybenzoic acid, tartaric acid, malic acid, glutamic acid, and threonine, all of which inhibited the growth and spore formation of Fusarium commun. In a wheat‐faba bean intercropping system, these six compounds found in the root exudate of non‐host wheat can help control Fusarium wilt in faba bean by inhibiting the mycelial growth and sporulation of Fusarium commun. [ABSTRACT FROM AUTHOR]

This study investigated the intricate interplay between Crimean‐Congo hemorrhagic fever virus (CCHFV) infection and alterations in amino acid metabolism. Our primary aim is to elucidate the impact of Crimean‐Congo hemorrhagic fever (CCHF) on specific amino acid concentrations and identify potential metabolic markers associated with viral infection. One hundred ninety individuals participated in this study, comprising 115 CCHF patients, 30 CCHF negative patients, and 45 healthy controls. Liquid chromatography‐tandem mass spectrometry techniques were employed to quantify amino acid concentrations. The amino acid metabolic profiles in CCHF patients exhibit substantial distinctions from those in the control group. Patients highlight distinct metabolic reprogramming, notably characterized by arginine, histidine, taurine, glutamic acid, and glutamine metabolism shifts. These changes have been associated with the underlying molecular mechanisms of the disease. Exploring novel therapeutic and diagnostic strategies addressing specific amino acids may offer potential means to mitigate the severity of the disease. [ABSTRACT FROM AUTHOR]

This study investigated the intricate interplay between Crimean‐Congo hemorrhagic fever virus infection and alterations in amino acid metabolism. The primary aim is to elucidate the impact of Crimean‐Congo hemorrhagic fever (CCHF) on specific amino acid concentrations and identify potential metabolic markers associated with viral infection. One hundred ninety individuals participated in this study, comprising 115 CCHF patients, 30 CCHF negative patients, and 45 healthy controls. Liquid chromatography‐tandem mass spectrometry techniques were employed to quantify amino acid concentrations. The amino acid metabolic profiles in CCHF patients exhibit substantial distinctions from those in the control group. Patients highlight distinct metabolic reprogramming, notably characterized by arginine, histidine, taurine, glutamic acid, and glutamine metabolism shifts. These changes have been associated with the underlying molecular mechanisms of the disease. Exploring novel therapeutic and diagnostic strategies addressing specific amino acids may offer potential means to mitigate the severity of the disease. [ABSTRACT FROM AUTHOR]

The foreign body response (FBR) to implanted biomaterials and biomedical devices can severely impede their functionality and even lead to failure. The discovery of effective anti‐FBR materials remains a formidable challenge. Inspire by the enrichment of glutamic acid (E) and lysine (K) residues on human protein surfaces, a class of zwitterionic polypeptide (ZIP) hydrogels with alternating E and K sequences to mitigate the FBR is prepared. When subcutaneously implanted, the ZIP hydrogels caused minimal inflammation after 2 weeks and no obvious collagen capsulation after 6 months in mice. Importantly, these hydrogels effectively resisted the FBR in non‐human primate models for at least 2 months. In addition, the enzymatic degradability of the gel can be controlled by adjusting the crosslinking degree or the optical isomerism of amino acid monomers. The long‐term FBR resistance and controlled degradability of ZIP hydrogels open up new possibilities for a broad range of biomedical applications. [ABSTRACT FROM AUTHOR]

Background: Thyroid cancer (TC) is the predominant malignancy within the endocrine system. However, the standard method for TC diagnosis lacks the capability to identify the pathological condition of all thyroid lesions. The metabolomics approach has the potential to manage this problem by identifying differential metabolites. Aims: This study conducted a systematic review and meta‐analysis of the NMR‐based metabolomics studies in order to identify significant altered metabolites associated with TC. Methods: A systematic search of published literature in any language in three databases including Embase, PubMed, and Scopus was conducted. Out of 353 primary articles, 12 studies met the criteria for inclusion in the systematic review. Among these, five reports belonging to three articles were eligible for meta‐analysis. The correlation coefficient of the orthogonal partial least squares discriminant analysis, a popular model in the multivariate statistical analysis of metabolomic data, was chosen for meta‐analysis. The altered metabolites were chosen based on the fact that they had been found in at least three studies. Results: In total, 49 compounds were identified, 40 of which were metabolites. The increased metabolites in thyroid lesions compared normal samples included lactate, taurine, alanine, glutamic acid, glutamine, leucine, lysine, phenylalanine, serine, tyrosine, valine, choline, glycine, and isoleucine. Lipids were the decreased compounds in thyroid lesions. Lactate and alanine were increased in malignant versus benign thyroid lesions, while, myo‐inositol, scyllo‐inositol, citrate, choline, and phosphocholine were found to be decreased. The meta‐analysis yielded significant results for three metabolites of lactate, alanine, and citrate in malignant versus benign specimens. Discussion: In this study, we provided a concise summary of 12 included metabolomic studies, making it easier for future researchers to compare their results with the prior findings. Conclusion: It appears that the field of TC metabolomics will experience notable advancement, leading to the discovery of trustworthy diagnostic and prognostic biomarkers. [ABSTRACT FROM AUTHOR]

Amino acids are necessary for all life forms, which play various roles. Disorder of amino acid metabolism is now considered an important driving mechanism in diverse pulmonary conditions, particularly chronic lung diseases like chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis and lung cancer. Glutamate actively participates in multiple vital biological processes, while the intricate glutamate metabolism, glutamate receptors and glutamate transporters assume crucial regulatory functions in the development of chronic lung diseases. This review aims to discuss the relationship between glutamate dysfunction and chronic lung diseases. By discussing the physiological and pathological function of glutamate, we probe the potential drug targets for chronic lung diseases in the glutamate pathway. [ABSTRACT FROM AUTHOR]

Mineral plastics are a promising class of bio‐inspired materials that offer exceptional properties, like self‐heal ability, stretchability in the hydrogel state, and high hardness, toughness, transparency, and non‐flammability in the dry state along with reversible transformation into the hydrogel by addition of water. This enables easy reshape‐ability and recycling like the solubility in mild acids to subsequently form mineral plastics again by base addition. However, current mineral plastics rely on petrochemistry, are hardly biodegradable, and thus persistent in nature. This work presents the next generation of mineral plastics, which are bio‐based and biodegradable, making them a promising, new class of polymers for the development of environmentally friendly materials. Physically cross‐linked (poly)glutamic‐acid (PGlu)‐based mineral plastics are synthesized using various alcohol‐water mixtures, metal ion ratios and molecular weights. The rheological properties are easily adjusted using these parameters. The general procedure involves addition of equimolar solution of CaCl2 to PGlu in equal volumes followed by addition of iPrOH (iPrOH:H2O = 1:1) under vigorous stirring conditions. The ready biodegradability of PGlu/CaFe mineral plastic is confirmed in this study where the elements N, Ca, and Fe present in it tend to act as additional nutrients, supporting the growth of microorganisms and consequently, promoting the biodegradation process. [ABSTRACT FROM AUTHOR]