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In recent years, cyclic peptides have emerged as a promising therapeutic modality due to their diverse biological activities. Understanding the structures of these cyclic peptides and their complexes is crucial for unlocking invaluable insights about protein target-cyclic peptide interaction, which can facilitate the development of novel-related drugs. However, conducting experimental observations is time-consuming and expensive. Computer-aided drug design methods are not practical enough in real-world applications. To tackles this challenge, we introduce HighFold, an AlphaFold-derived model in this study. By integrating specific details about the head-to-tail circle and disulfide bridge structures, the HighFold model can accurately predict the structures of cyclic peptides and their complexes. Our model demonstrates superior predictive performance compared to other existing approaches, representing a significant advancement in structure-activity research. The HighFold model is openly accessible at https://github.com/hongliangduan/HighFold.
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Dissulfetos , Peptídeos Cíclicos , Peptídeos Cíclicos/química , Dissulfetos/química , Software , Modelos Moleculares , Conformação Proteica , Algoritmos , Biologia Computacional/métodosRESUMO
Protein-peptide interactions (PPepIs) are vital to understanding cellular functions, which can facilitate the design of novel drugs. As an essential component in forming a PPepI, protein-peptide binding sites are the basis for understanding the mechanisms involved in PPepIs. Therefore, accurately identifying protein-peptide binding sites becomes a critical task. The traditional experimental methods for researching these binding sites are labor-intensive and time-consuming, and some computational tools have been invented to supplement it. However, these computational tools have limitations in generality or accuracy due to the need for ligand information, complex feature construction, or their reliance on modeling based on amino acid residues. To deal with the drawbacks of these computational algorithms, we describe a geometric attention-based network for peptide binding site identification (GAPS) in this work. The proposed model utilizes geometric feature engineering to construct atom representations and incorporates multiple attention mechanisms to update relevant biological features. In addition, the transfer learning strategy is implemented for leveraging the protein-protein binding sites information to enhance the protein-peptide binding sites recognition capability, taking into account the common structure and biological bias between proteins and peptides. Consequently, GAPS demonstrates the state-of-the-art performance and excellent robustness in this task. Moreover, our model exhibits exceptional performance across several extended experiments including predicting the apo protein-peptide, protein-cyclic peptide and the AlphaFold-predicted protein-peptide binding sites. These results confirm that the GAPS model is a powerful, versatile, stable method suitable for diverse binding site predictions.
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Peptídeos , Sítios de Ligação , Peptídeos/química , Peptídeos/metabolismo , Ligação Proteica , Biologia Computacional/métodos , Algoritmos , Proteínas/química , Proteínas/metabolismo , Aprendizado de MáquinaRESUMO
Systematic integration of lncRNA-disease associations is of great importance for further understanding their underlying molecular mechanisms and exploring lncRNA-based biomarkers and therapeutics. The database of long non-coding RNA-associated diseases (LncRNADisease) is designed for the above purpose. Here, an updated version (LncRNADisease v3.0) has curated comprehensive lncRNA (including circRNA) and disease associations from the burgeoning literatures. LncRNADisease v3.0 exhibits an over 2-fold increase in experimentally supported associations, with a total of 25440 entries, compared to the last version. Besides, each lncRNA-disease pair is assigned a confidence score based on experimental evidence. Moreover, all associations between lncRNAs/circRNAs and diseases are classified into general associations and causal associations, representing whether lncRNAs or circRNAs can directly lead to the development or progression of corresponding diseases, with 15721 and 9719 entries, respectively. In a case study, we used the data of LncRNADisease v3.0 to calculate the phenotypic similarity between human and mouse lncRNAs. This database will continue to serve as a valuable resource for potential clinical applications related to lncRNAs and circRNAs. LncRNADisease v3.0 is freely available at http://www.rnanut.net/lncrnadisease.
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Bases de Dados de Ácidos Nucleicos , Doença , RNA Longo não Codificante , Animais , Humanos , Camundongos , Bases de Dados Genéticas , RNA Circular , RNA Longo não Codificante/genética , Doença/genéticaRESUMO
Interlayer excitons, with prolonged lifetimes and tunability, hold potential for advanced optoelectronics. Previous research on the interlayer excitons has been dominated by two-dimensional heterostructures. Here, we construct WSe2/GaN composite heterostructures, in which the doping concentration of GaN and the twist angle of bilayer WSe2 are employed as two ingredients for the manipulation of exciton behaviors and polarizations. The exciton energies in monolayer WSe2/GaN can be regulated continuously by the doping levels of the GaN substrate, and a remarkable increase in the valley polarizations is achieved. Especially in a heterostructure with 4°-twisted bilayer WSe2, a maximum polarization of 38.9% with a long lifetime is achieved for the interlayer exciton. Theoretical calculations reveal that the large polarization and long lifetime are attributed to the high exciton binding energy and large spin flipping energy during depolarization in bilayer WSe2/GaN. This work introduces a distinctive member of the interlayer exciton with a high degree of polarization and a long lifetime.
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Charge and spin are two intrinsic attributes of carriers governing almost all of the physical processes and operation principles in materials. Here, we demonstrate the manipulation of electronic and spin states in designed Co-quantum dot/WS2 (Co-QDs/WS2) heterostructures by employing a metal-dielectric composite substrate and via scanning tunneling microscope. By repeatedly scanning under a unipolar bias, switching the bias polarity, or applying a pulse through nonmagnetic or magnetic tips, the Co-QDs morphologies exhibit a regular and reproducible transformation between bright and dark dots. First-principles calculations reveal that these tunable characters are attributed to the variation of density of states and the transition of magnetic anisotropy energy induced by carrier accumulation. It also suggests that the metal-dielectric composite substrate is successful in creating the interfacial potential for carrier accumulation and realizes the electrically controllable modulations. These results will promote the exploration of electron-matter interactions in quantum systems and provide an innovative way to facilitate the development of spintronics.
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BACKGROUND: Surfactin, a green lipopeptide bio-surfactant, exhibits excellent surface, hemolytic, antibacterial, and emulsifying activities. However, a lack of clear understanding of the synthesis regulation mechanism of surfactin homologue components has hindered the customized production of surfactin products with different biological activities. RESULTS: In this study, exogenous valine and 2-methylbutyric acid supplementation significantly facilitated the production of C14-C15 surfactin proportions (up to 75% or more), with a positive correlation between the homologue proportion and fortified concentration. Subsequently, the branched-chain amino acid degradation pathway and the glutamate synthesis pathway are identified as critical pathways in regulating C14-C15 surfactin synthesis by transcriptome analysis. Overexpression of genes bkdAB and glnA resulted in a 1.4-fold and 1.3-fold increase in C14 surfactin, respectively. Finally, the C14-rich surfactin was observed to significantly enhance emulsification activity, achieving an EI24 exceeding 60% against hexadecane, while simultaneously reducing hemolytic activity. Conversely, the C15-rich surfactin demonstrated an increase in both hemolytic and antibacterial activities. CONCLUSION: This study presents the first evidence of a potential connection between surfactin homologue synthesis and the conversion of glutamate and glutamine, providing a theoretical basis for targeting the synthesis regulation and structure-activity relationships of surfactin and other lipopeptide compounds.
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Ácidos Graxos , Tensoativos , Ácidos Graxos/metabolismo , Tensoativos/metabolismo , Ácido Glutâmico/metabolismo , Lipopeptídeos , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Peptídeos Cíclicos/química , Bacillus subtilis/genéticaRESUMO
With the rapid development of nanotechnology and biomedicine, numerous gadolinium (Gd)-based nanoparticle MRI contrast agents have been widely investigated. Due to the unique physicochemical properties of nanoparticles and the complexity of biological systems, the biosafety of Gd-based nanoparticle MRI contrast agents has been paid more and more attention. Herein, for the first time, we employed an ultra-high performance liquid chromatography-electrospray ionization quadrupole time-of-flight/mass spectrometry (UPLC-ESI-QTOF/MS)-based metabolomics approach to investigate the potential toxicity of Gd-based nanoparticle MRI contrast agents. In this work, NaGdF4 and PEG-NaGdF4 nanoparticles were successfully constructed and selected as the representative Gd-based nanoparticle MRI contrast agents for the metabolomics analysis. Based on the results of metabolomics, more metabolic biomarkers and pathways were identified in the NaGdF4 group than those in the PEG-NaGdF4 group. Careful analysis of these metabolic biomarkers and pathways suggested that NaGdF4 nanoparticles induced disturbance of pyrimidine and purine metabolism, inflammatory response, and kidney injury to a certain extent compared with PEG-NaGdF4 nanoparticles. These results indicated that Gd-based nanoparticle contrast agents modified with PEG had better biosafety. Additionally, it was demonstrated that the discovery of characteristic metabolomics biomarkers induced by nanoparticles would provide a new approach for biosafety assessment and stimulate the development of nanomedicine.
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Meios de Contraste , Nanopartículas , Meios de Contraste/toxicidade , Meios de Contraste/química , Contenção de Riscos Biológicos , Gadolínio/química , Nanopartículas/toxicidade , Nanopartículas/química , Imageamento por Ressonância Magnética/métodos , BiomarcadoresRESUMO
Aeromonas hydrophila, the pathogen that is the causative agent of motile Aeromonas septicemia (MAS) disease, commonly attacks freshwater fishes, including yellow catfish (Pelteobagrus fulvidraco). Although the kidney is one of the most important organs involved in immunity in fish, its role in disease progression has not been fully elucidated. Understanding the cellular composition and innate immune regulation mechanisms of the kidney of yellow catfish is important for the treatment of MAS. In this study, single-cell RNA sequencing (scRNA-seq) was performed on the kidney of hybrid yellow catfish (Pelteobagrus fulvidraco â × Pelteobagrus vachelli â) after A. hydrophila infection. Nine types of kidney cells were identified using marker genes, and a transcription module of marker genes in the main immune cells of hybrid yellow catfish kidney tissue was constructed using in-situ hybridization. In addition, the single-cell transcriptome data showed that the differentially expressed genes of macrophages were primarily enriched in the Toll-like receptor and Nod-like receptor signaling pathways. The expression levels of genes involved in these pathways were upregulated in macrophages following A. hydrophila infection. Transmission electron microscopy and TUNEL analysis revealed the cellular characteristics of macrophages before and after A. hydrophila infection. These data provide empirical support for in-depth research on the role of the kidney in the innate immune response of hybrid yellow catfish.
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Aeromonas hydrophila , Peixes-Gato , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Imunidade Inata , Rim , Transcriptoma , Animais , Peixes-Gato/imunologia , Peixes-Gato/genética , Aeromonas hydrophila/fisiologia , Doenças dos Peixes/imunologia , Imunidade Inata/genética , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Transcriptoma/imunologia , Rim/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Análise de Célula ÚnicaRESUMO
Facial palsy therapies based on cortical plasticity are in development, but facial synkinesis progress is limited. Studying neural plasticity characteristics, especially network organization and its constitutive elements (nodes/edges), is the key to overcome the bottleneck. We studied 55 participants (33 facial synkinesis patients, 22 healthy controls) with clinical assessments, functional magnetic resonance imaging (fMRI), and diffusion tensor imaging (DTI). We analyzed rich-club organization and metrics of structural brain networks (rich-club coefficients, strength, degree, density, and efficiency). Functional brain network metrics, including functional connectivity and its coupling with the structural network, were also computed. Patients displayed reduced strength and density of rich-club nodes and edges, as well as decreased global efficiency. All nodes exhibited decreased nodal efficiency in patients. Patients had significantly increased functional connectivity and decreased structural-functional coupling strength in rich-club nodes, rich-club edges, and feeder edges. Our study indicates that facial synkinesis patients have weakened structural connections but enhanced functional transmission from rich-club nodes. The loss of connections and efficiency in structural network may trigger compensatory increases in functional connectivity of rich-club nodes. Two potential biomarkers, rich-club edge density and structural-functional coupling strength, may serve as indicators of disease outcome. These findings provide valuable insights into synkinesis mechanisms and offer potential targets for cortical intervention.
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Imagem de Tensor de Difusão , Sincinesia , Humanos , Sincinesia/diagnóstico por imagem , Sincinesia/patologia , Encéfalo , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagemRESUMO
With childhood hypertension emerging as a global public health concern, understanding its associated factors is crucial. This study investigated the prevalence and associated factors of hypertension among Chinese children. This cross-sectional investigation was conducted in Pinghu, Zhejiang province, involving 2,373 children aged 8-14 years from 12 schools. Anthropometric measurements were taken by trained staff. Blood pressure (BP) was measured in three separate occasions, with an interval of at least two weeks. Childhood hypertension was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ≥ age-, sex-, and height-specific 95th percentile, across all three visits. A self-administered questionnaire was utilized to collect demographic, socioeconomic, health behavioral, and parental information at the first visit of BP measurement. Random forest (RF) and multivariable logistic regression model were used collectively to identify associated factors. Additionally, population attributable fractions (PAFs) were calculated. The prevalence of childhood hypertension was 5.0% (95% confidence interval [CI]: 4.1-5.9%). Children with body mass index (BMI) ≥ 85th percentile were grouped into abnormal weight, and those with waist circumference (WC) > 90th percentile were sorted into central obesity. Normal weight with central obesity (NWCO, adjusted odds ratio [aOR] = 5.04, 95% CI: 1.96-12.98), abnormal weight with no central obesity (AWNCO, aOR = 4.60, 95% CI: 2.57-8.21), and abnormal weight with central obesity (AWCO, aOR = 9.94, 95% CI: 6.06-16.32) were associated with an increased risk of childhood hypertension. Childhood hypertension was attributable to AWCO mostly (PAF: 0.64, 95% CI: 0.50-0.75), followed by AWNCO (PAF: 0.34, 95% CI: 0.19-0.51), and NWCO (PAF: 0.13, 95% CI: 0.03-0.30). Our results indicated that obesity phenotype is associated with childhood hypertension, and the role of weight management could serve as potential target for intervention.
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Hipertensão , Humanos , Estudos Transversais , Masculino , Feminino , Hipertensão/epidemiologia , China/epidemiologia , Criança , Prevalência , Adolescente , Fatores de Risco , Modelos Logísticos , Algoritmo Florestas AleatóriasRESUMO
Huangjiu is a spontaneously fermented alcoholic beverage, that undergoes intricate microbial compositional changes. This study aimed to unravel the flavor and quality formation mechanisms based on the microbial metabolism of Huangjiu. Here, metagenome techniques, chemometrics analysis, and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) metabolomics combined with microbial metabolic network were employed to investigate the distinctions and relationship between the microbial profiles and the quality characteristics, flavor metabolites, functional metabolic patterns of Huangjiu across three regions. Significant variations (P < 0.05) were observed in metabolic rate of physicochemical parameters and biogenic amine concentration among three regions. 8 aroma compounds (phenethyl acetate, phenylethyl alcohol, isobutyl alcohol, ethyl octanoate, ethyl acetate, ethyl hexanoate, isoamyl alcohol, and diethyl succinate) out of 448 volatile compounds were identified as the regional chemical markers. 25 dominant microbial genera were observed through metagenomic analysis, and 13 species were confirmed as microbial markers in three regions. A metabolic network analysis revealed that Saccharomycetales (Saccharomyces), Lactobacillales (Lactobacillus, Weissella, and Leuconostoc), and Eurotiales (Aspergillus) were the predominant populations responsible for substrate, flavor (mainly esters and phenylethyl alcohol) metabolism, Lactobacillales and Enterobacterales were closely linked with biogenic amine. These findings provide scientific evidence for regional microbial contributions to geographical characteristics of Huangjiu, and perspectives for optimizing microbial function to promote Huangjiu quality.
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Bactérias , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Redes e Vias Metabólicas , Metagenômica , Oryza , Compostos Orgânicos Voláteis , Vinho , Bactérias/classificação , Bactérias/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Aminas Biogênicas/análise , Aminas Biogênicas/metabolismo , China , Aromatizantes/metabolismo , Aromatizantes/química , Metabolômica/métodos , Microbiota , Odorantes/análise , Oryza/microbiologia , Oryza/química , Oryza/metabolismo , Microextração em Fase Sólida , Paladar , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/análise , Vinho/análise , Vinho/microbiologiaRESUMO
Predicting individual prognosis is difficult despite various risk factor studies, due to the complex recovery involving peripheral nerve restoration and cerebral plasticity. This study uses fixel-based analysis (FBA) to better understand neural pathway alterations, hypothesizing that FBA can effectively link functional outcomes with diffusion metrics in the process of rehabilitation. The authors recruited 50 participants including 30 patients and 20 healthy controls into the study. All of them underwent assessment 3 months and 6 months after injury. Both whole-brain fixel-based analysis and tract of interest analysis were performed. The authors observed multiple regions including the superior corona radiata, posterior limb of the internal capsule, and cerebral peduncle displaying significant changes of FD (fiber density), FC (fiber-bundle cross-section), and FDC (fiber density and cross-section). Patients with unfavorable outcomes showed increased FD in the ipsilesional side and decreased FD in the contralesional side compared with patients with favorable outcomes. In addition, FD values of the contralesional side exhibited positive correlations with differences in FGS at 3 months and 6 months. Conversely, FD values in the ipsilesional side showed a negative correlation. Our findings suggest that FD metrics within the corticobulbar tract could serve as predictive biomarkers for symmetry outcomes. Thus, FBA holds promise for early estimation of behavioral outcomes in facial palsy, guiding more targeted interventions.
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Although wind power contributes to the reduction of greenhouse gas emissions, it also has significant impacts on the local climate and vegetation. Exploring these impacts is important for the sustainable development of wind power. Therefore, based on moderate-resolution imaging spectroradiometer (MODIS) data and other remote sensing data from 2003 to 2022, this paper investigated the impacts of 101 grassland wind farms (WFs) in Inner Mongolia on land-atmosphere water and heat exchange, vegetation growth, ecosystem primary productivity, and vegetation structural characteristics during the growing season and revealed the spatial distribution patterns of the impacts of WFs as well as differences between different types of grasslands. The results indicated that WFs increased the nighttime land surface temperature (LST), decreased evapotranspiration (ET), inhibited vegetation growth, decreased gross primary productivity (GPP), and reduced the leaf area index (LAI) in growing season grasslands. This effect varied across different types of grasslands and showed significant complexity. In terms of land-atmosphere water and heat exchange, nighttime LST increases and ET decreases were significant in the typical steppe but not in the meadow steppe. In terms of vegetation change, meadow steppe had the most inhibited vegetation growth and the greatest reduction in GPP. In terms of the impact range, WFs on typical steppe and meadow steppe have opposite effects on vegetation growth and ecosystem primary productivity inside and outside of them, i.e., they inhibit vegetation growth and reduce GPP inside the WF areas but promote vegetation growth and increase GPP outside the WF areas. Compared with previous studies, this study analyzed multiple climate and vegetation indicators based on many WF samples, which reduced the uncertainty associated with a single sample and provided more comprehensive and comparable observations of different types of grasslands. These findings can help to balance the relationship between wind power development and ecological protection.
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Plant height (PH) is an important trait affecting the plant architecture, seed yield, and harvest index. However, the molecular mechanisms underlying PH heterosis remain unclear. In addition, useful PH-related genes must be urgently identified to facilitate ideal plant architecture breeding in rice (Oryza sativa L.). In the present study, to explore rice quantitative trait loci (QTLs) and heterosis-related loci of PH in rice, we developed a high-generation (>F15 ) population of 272 recombinant inbred lines (RIL) from a cross of two elite varieties, Luohui 9 (indica/xian) × RPY geng (japonica/geng), and two testcross hybrid populations derived from the crosses of RILs and two cytoplasmic male sterile lines (YTA [indica] and Z7A [japonica]). Using deep resequencing data, a high-density genetic map containing 4758 bin markers was constructed, with a total map distance of 2356.41 cM. Finally, 31 PH-related QTLs for different PH component lengths or tiller numbers across five seasons were identified. Two major environment-specific PH QTLs were stably detected in Hainan (qPH-3.1) or Hubei (qPH-5.1), which have undergone significant functional alterations in rice with changes in geographical environment. Based on comparative genomics, gene function annotation, homolog identification, and existing literature (pioneering studies), candidate genes for multiple QTLs were fine-mapped, and the candidate genes qPH-3.1 and qPH-5.1 for PH were further validated using CRISPR-Cas9 gene editing. Specifically, qPH-3.1 was characterized as a pleiotropic gene, and the qPH-3.1 knockout line showed reduced PH, delayed heading, a decreased seed setting rate, and increased tiller numbers. Importantly, 10 PH heterosis-related QTLs were identified in the testcross populations, and a better-parent heterosis locus (qBPH-5.2) completely covered qPH-5.1. Furthermore, the cross results of fixed-genotype RILs verified the dominant effects of qPH-3.1 and qPH-5.1. Together, these findings further our understanding of the genetic mechanisms of PH and offer multiple highly reliable gene targets for breeding rice varieties with ideal architecture and high yield potential in the immediate future.
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Vigor Híbrido , Oryza , Mapeamento Cromossômico/métodos , Genes de Plantas , Ligação Genética , Vigor Híbrido/genética , Oryza/genética , Fenótipo , Melhoramento Vegetal , Locos de Características Quantitativas/genéticaRESUMO
The maintenance of a proton gradient across the thylakoid membrane is an integral aspect of photosynthesis that is mainly established by the splitting of water molecules in photosystem II and plastoquinol oxidation at the cytochrome complex, and it is necessary for the generation of ATP in the last step of photophosphorylation. Although environmental stresses, such as high temperatures, are known to disrupt this fundamental process, only a few studies have explored the molecular mechanisms underlying proton gradient regulation during stress. The present study identified a heat-sensitive mutant that displays aberrant photosynthesis at high temperatures. This mutation was mapped to AtFtsH11, which encodes an ATP-dependent AAA-family metalloprotease. We showed that AtFtsH11 localizes to the chloroplast inner envelope membrane and is capable of degrading the ATP synthase assembly factor BFA3 under heat stress. We posit that this function limits the amount of ATP synthase integrated into the thylakoid membrane to regulate proton efflux from the lumen to the stroma. Our data also suggest that AtFtsH11 is critical in stabilizing photosystem II and cytochrome complexes at high temperatures, and additional studies can further elucidate the specific molecular functions of this critical regulator of photosynthetic thermotolerance.
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Arabidopsis , ATPases de Cloroplastos Translocadoras de Prótons , ATPases de Cloroplastos Translocadoras de Prótons/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Prótons , Arabidopsis/genética , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Fotossíntese/fisiologia , Resposta ao Choque Térmico , Trifosfato de Adenosina/metabolismo , Citocromos/metabolismoRESUMO
Fermented foods are important parts of traditional food culture with a long history worldwide. Abundant nutritional materials and open fermentation contribute to the diversity of microorganisms, resulting in unique product quality and flavor. Lactic acid bacteria (LAB), as important part of traditional fermented foods, play a decisive role in the quality and safety of fermented foods. Reproduction and metabolic of microorganisms drive the food fermentation, and microbial interaction plays a major role in the fermentation process. Nowadays, LAB have attracted considerable interest due to their potentialities to add functional properties to certain foods or as supplements along with the research of gut microbiome. This review focuses on the characteristics of diversity and variability of LAB in traditional fermented foods, and describes the principal mechanisms involved in the flavor formation dominated by LAB. Moreover, microbial interactions and their mechanisms in fermented foods are presented. They provide a theoretical basis for exploiting LAB in fermented foods and improving the quality of traditional fermented foods. The traditional fermented food industry should face the challenge of equipment automation, green manufacturing, and quality control and safety in the production.
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Alimentos Fermentados , Lactobacillales , Lactobacillales/metabolismo , Alimentos Fermentados/microbiologia , Alimentos , Fermentação , Microbiologia de AlimentosRESUMO
This paper presents the common methods and corresponding drawbacks concerning nonlinear analysis of fluxgate excitation circuits and emphasizes the importance of nonlinear analysis for these circuits. With regard to the nonlinearity of the excitation circuit, this paper proposes the use of the core-measured hysteresis curve for mathematical analysis and the use of a nonlinear model that considers the coupling effect of the core and winding and influence of the historical magnetic field on the core for simulation analysis. The feasibility of mathematical calculations and simulation for the nonlinear study of fluxgate excitation circuit is verified via experiments. The results demonstrate that, in this regard, the simulation is four times better than a mathematical calculation. The simulation and experimental results of the excitation current and voltage waveforms under different excitation circuit parameters and structures are essentially consistent, with a difference in current of no more than 1 mA, thereby verifying the effectiveness of the nonlinear excitation analysis method.
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The CYP76 subfamily, a member of the CYP superfamily, plays crucial roles in the biosynthesis of phytohormones in plants, involving biosynthesis of secondary metabolites, hormone signaling, and response to environmental stresses. Here, we conducted a genome-wide analysis of the CYP76 subfamily in seven AA genome species: Oryza sativa ssp. japonica, Oryza sativa ssp. indica, Oryza rufipogon, Oryza glaberrima, Oryza meridionalis, Oryza barthii, and Oryza glumaepatula. These were identified and classified into three groups, and it was found that Group 1 contained the largest number of members. Analysis of cis-acting elements revealed a large number of elements related to jasmonic acid and light response. The gene duplication analysis revealed that the CYP76 subfamily expanded mainly in SD/WGD and tandem forms and underwent strong purifying selection during evolution. Expression pattern analysis of OsCYP76s in various developmental stages revealed that the majority of OsCYP76s exhibit relatively restricted expression patterns in leaves and roots. We further analyzed the expression of CYP76s in O. sativa, japonica, and O. sativa, indica under cold, flooding, drought, and salt abiotic stresses by qRT-PCR. We found that OsCYP76-11 showed a huge increase in relative expression after drought and salt stresses. After flooding stress, OsiCYP76-4 showed a greater increase in expression compared to other genes. CYP76 in japonica and indica showed different response patterns to the same abiotic stresses, revealing functional divergence in the gene family during evolution; these may be the key genes responsible for the differences in tolerance to indica japonica. Our results provide valuable insights into the functional diversity and evolutionary history of the CYP76 subfamily and pave the way for the development of new strategies for improving stress tolerance and agronomic traits in rice.
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Oryza , Oryza/genética , Oryza/metabolismo , Duplicação Gênica , Estresse Fisiológico/genética , Estresse Salino , Reação em Cadeia da Polimerase , Filogenia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
BACKGROUND: Oleogels have been extensively explored as fat substitutes with no trans fatty acids and low saturated fatty acids in recent years as a result of increased health problems found to be related to the intake of trans and saturated fatty acids. RESULTS: Herein, high internal phase emulsion (HIPE) stabilized by rice bran protein (RBP) was prepared and further utilized as a template for preparation of RBP oleogels. RBP HIPE with the strongest rheological properties was obtained at pH 5.0 as a result of appropriate structural deformation, surface charge and a high three-phase contact angle at this pH. However, RBP oleogels prepared at pH 9.0 exhibited the highest yield stress after drying process. At this pH, RBP showed higher resistance to deformation caused by water evaporation. This highlighted the importance of structural stability of protein network on rheological properties of the resultant oleogels. Furthermore, with an increase in drying temperature, RBP oleogels exhibited higher yield stress and gel strength because water was better removed as a result of an enhanced capability to overcome the capillary pressure of emulsion. CONCLUSION: The present study further revealed the structure-activity relationship between protein, HIPE and oleogel, and also provided theoretical support for the development of protein-based oleogel. © 2023 Society of Chemical Industry.
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Oryza , Oryza/química , Emulsões/química , Ácidos Graxos/química , ÁguaRESUMO
The electrochemical dinitrogen (N2 ) reduction reaction (NRR) under ambient conditions has gained significant interest as an environmentally friendly alternative to the traditional Haber-Bosch process for the synthesis of ammonia (NH3 ). However, up to now, most of the reported NRR electrocatalysts with satisfactory catalytic activities have been hindered by the large overpotential in N2 activation. The preparation of highly efficient Mo-based NRR electrocatalyst in acidic electrolytes under ambient conditions is demonstrated here, consisting of stabilized single Mo atoms anchored on holey nitrogen-doped graphene synthesized through a convenient potassium-salt-assisted activation method. At -0.05 V versus a reversible hydrogen electrode (RHE), an electrode consisting of the resultant electrocatalyst immobilized on carbon fiber paper can attain an exceptional Faradaic efficiency of 50.2% and a NH3 yield rate of 3.6 µg h-1 mgcat-1 with low overpotentials. Density functional theory calculations further unveil that compared to the original graphene without holes, the edge coordinated Mo atoms and the existence of vacancies on holey graphene lower the overpotential of N2 reduction, thereby promoting the NRR catalytic activity. This work could provide new guidelines for future designs in single-atom catalysis that would be beneficial to ambient N2 fixation, and replacement of classical synthesis processes that are very energy-intensive.