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1.
J Am Chem Soc ; 144(17): 7741-7749, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35438986

RESUMO

Luminol-based electrochemiluminescence (ECL) can be readily excited by various reactive oxygen species (ROS) electrogenerated with an oxygen reduction reaction (ORR). However, the multiple active intermediates involved in the ORR catalyzed with complex nanomaterials lead to recognizing the role of ROS still elusive. Moreover, suffering from the absence of the direct electrochemical oxidation of luminol at the cathode and poor transformation efficiency of O2 to ROS, the weak cathodic ECL emission of luminol is often neglected. Herein, owing to the tunable coordination environment and structure-dependent catalytic feature, single-atom catalysts (SACs) are employed to uncover the relationship between the intrinsic ORR activity and ECL behavior. Interestingly, the traditionally negligible cathodic ECL of luminol is first boosted (ca. 70-fold) owing to the combination of electrochemical ORR catalyzed via SACs and chemical oxidation of luminol. The boosted cathodic ECL emission exhibits electron-transfer pathway-dependent response by adjusting the surrounding environment of the center metal atoms in a controlled way to selectively produce different active intermediates. This work bridges the relationship between ORR performance and ECL behavior, which will guide the development of an amplified sensing platform through rational tailoring of the ORR activity of SACs and potential-resolved ECL assays based on the high-efficiency cathodic ECL reported.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Catálise , Técnicas Eletroquímicas , Eletrodos , Medições Luminescentes , Luminol , Oxigênio , Espécies Reativas de Oxigênio
2.
J Am Chem Soc ; 143(18): 6933-6941, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33915042

RESUMO

Interfacial electron engineering between noble metal and transition metal carbide is identified as a powerful strategy to improve the intrinsic activity of electrocatalytic oxygen reduction reaction (ORR). However, this short-range effect and the huge structural differences make it a significant challenge to obtain the desired electrocatalyst with atomically thin noble metal layers. Here, we demonstrated the combinatorial strategies to fabricate the heterostructure electrocatalyst of Mo2C-coupled Pd atomic layers (AL-Pd/Mo2C) by precise control of metal-organic framework confinement and covalent interaction. Both atomic characterizations and density functional theory calculations uncovered that the strong electron effect imposed on Pd atomic layers has intensively regulated the electronic structures and d-band center and then optimized the reaction kinetics. Remarkably, AL-Pd/Mo2C showed the highest ORR electrochemical activity and stability, which delivered a mass activity of 2.055 A mgPd-1 at 0.9 V, which is 22.1, 36.1, and 80.3 times higher than Pt/C, Pd/C, and Pd nanoparticles, respectively. The present work has developed a novel approach for atomically noble metal catalysts and provides new insights into interfacial electron regulation.

3.
Rep Prog Phys ; 84(12)2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34753115

RESUMO

Biomolecular recognition usually leads to the formation of binding complexes, often accompanied by large-scale conformational changes. This process is fundamental to biological functions at the molecular and cellular levels. Uncovering the physical mechanisms of biomolecular recognition and quantifying the key biomolecular interactions are vital to understand these functions. The recently developed energy landscape theory has been successful in quantifying recognition processes and revealing the underlying mechanisms. Recent studies have shown that in addition to affinity, specificity is also crucial for biomolecular recognition. The proposed physical concept of intrinsic specificity based on the underlying energy landscape theory provides a practical way to quantify the specificity. Optimization of affinity and specificity can be adopted as a principle to guide the evolution and design of molecular recognition. This approach can also be used in practice for drug discovery using multidimensional screening to identify lead compounds. The energy landscape topography of molecular recognition is important for revealing the underlying flexible binding or binding-folding mechanisms. In this review, we first introduce the energy landscape theory for molecular recognition and then address four critical issues related to biomolecular recognition and conformational dynamics: (1) specificity quantification of molecular recognition; (2) evolution and design in molecular recognition; (3) flexible molecular recognition; (4) chromosome structural dynamics. The results described here and the discussions of the insights gained from the energy landscape topography can provide valuable guidance for further computational and experimental investigations of biomolecular recognition and conformational dynamics.


Assuntos
Descoberta de Drogas , Proteínas , Conformação Molecular , Simulação de Dinâmica Molecular , Física , Ligação Proteica , Conformação Proteica , Proteínas/metabolismo
4.
BMC Plant Biol ; 21(1): 452, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34615485

RESUMO

BACKGROUND: Chinese bayberry (Myrica rubra Sieb. & Zucc.) is an important fruit tree in China, and has high medicinal value. At present, the genome, transcriptome and germplasm resources of bayberry have been reported. In order to make more convenient use of these data, the Bayberry Database was established. RESULTS: The Bayberry Database is a comprehensive and intuitive data platform for examining the diverse annotated genome and germplasm resources of this species. This database contains nine central functional domains to interact with multiomic data: home, genome, germplasm, markers, tools, map, expression, reference, and contact. All domains provide pathways to a variety of data types composed of a reference genome sequence, transcriptomic data, gene patterns, phenotypic data, fruit images of Myrica rubra varieties, gSSR data, gene maps with annotation and evolutionary analyses. The tools module includes BLAST search, keyword search, sequence fetch and enrichment analysis functions. CONCLUSIONS: The web address of the database is as follows http://www.bayberrybase.cn/ . The Myrica rubra database is an intelligent, interactive, and user-friendly system that enables researchers, breeders and horticultural personnel to browse, search and retrieve relevant and useful information and thus facilitate genomic research and breeding efforts concerning Myrica rubra. This database will be of great help to bayberry research and breeding in the future.


Assuntos
Produtos Agrícolas/genética , Bases de Dados Factuais , Genoma de Planta , Myrica/genética , Plantas Medicinais/genética , Transcriptoma , Árvores/genética , China , Variação Genética , Genótipo
5.
J Biol Chem ; 293(15): 5431-5446, 2018 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-29487133

RESUMO

Heme cytotoxicity is minimized by a two-step catabolic reaction that generates biliverdin (BV) and bilirubin (BR) tetrapyrroles. The second step is regulated by two non-redundant biliverdin reductases (IXα (BLVRA) and IXß (BLVRB)), which retain isomeric specificity and NAD(P)H-dependent redox coupling linked to BR's antioxidant function. Defective BLVRB enzymatic activity with antioxidant mishandling has been implicated in metabolic consequences of hematopoietic lineage fate and enhanced platelet counts in humans. We now outline an integrated platform of in silico and crystallographic studies for the identification of an initial class of compounds inhibiting BLVRB with potencies in the nanomolar range. We found that the most potent BLVRB inhibitors contain a tricyclic hydrocarbon core structure similar to the isoalloxazine ring of flavin mononucleotide and that both xanthene- and acridine-based compounds inhibit BLVRB's flavin and dichlorophenolindophenol (DCPIP) reductase functions. Crystallographic studies of ternary complexes with BLVRB-NADP+-xanthene-based compounds confirmed inhibitor binding adjacent to the cofactor nicotinamide and interactions with the Ser-111 side chain. This residue previously has been identified as critical for maintaining the enzymatic active site and cellular reductase functions in hematopoietic cells. Both acridine- and xanthene-based compounds caused selective and concentration-dependent loss of redox coupling in BLVRB-overexpressing promyelocytic HL-60 cells. These results provide promising chemical scaffolds for the development of enhanced BLVRB inhibitors and identify chemical probes to better dissect the role of biliverdins, alternative substrates, and BLVRB function in physiologically relevant cellular contexts.


Assuntos
Inibidores Enzimáticos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , 2,6-Dicloroindofenol/química , 2,6-Dicloroindofenol/farmacologia , Coenzimas/química , Coenzimas/metabolismo , Simulação por Computador , Cristalografia por Raios X , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Células HL-60 , Humanos , Niacinamida/química , Niacinamida/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/química , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo
6.
BMC Genomics ; 20(1): 458, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31170907

RESUMO

BACKGROUND: Chinese bayberry (Myrica rubra Sieb. & Zucc.) is an economically important fruit tree characterized by its juicy fruits rich in antioxidant compounds. Elucidating the genetic basis of the biosynthesis of active antioxidant compounds in bayberry is fundamental for genetic improvement of bayberry and industrial applications of the fruit's antioxidant components. Here, we report the genome sequence of a multiple disease-resistant bayberry variety, 'Zaojia', in China, and the transcriptome dynamics in the course of fruit development. RESULTS: A 289.92 Mb draft genome was assembled, and 26,325 protein-encoding genes were predicted. Most of the M. rubra genes in the antioxidant signaling pathways had multiple copies, likely originating from tandem duplication events. Further, many of the genes found here present structural variations or amino acid changes in the conserved functional residues across species. The expression levels of antioxidant genes were generally higher in the early stages of fruit development, and were correlated with the higher levels of total flavonoids and antioxidant capacity, in comparison with the mature fruit stages. Based on both gene expression and biochemical analyses, five genes, namely, caffeoyl-CoA O-methyltransferase, anthocyanidin 3-O-glucosyltransferase, (+)-neomenthol dehydrogenase, gibberellin 2-oxidase, and squalene monooxygenase, were suggested to regulate the flavonoid, anthocyanin, monoterpenoid, diterpenoid, and sesquiterpenoid/triterpenoid levels, respectively, during fruit development. CONCLUSIONS: This study describes both the complete genome and transcriptome of M. rubra. The results provide an important basis for future research on the genetic improvement of M. rubra and contribute to the understanding of its genetic evolution. The genome sequences corresponding to representative antioxidant signaling pathways can help revealing useful traits and functional genes.


Assuntos
Genoma de Planta , Myrica/genética , Antioxidantes/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Genômica , Myrica/crescimento & desenvolvimento , Myrica/metabolismo , Transcriptoma
7.
Chaos ; 29(8): 083133, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31472512

RESUMO

The link prediction aims at predicting missing or future links in networks, which provides theoretical significance and extensive applications in the related field. However, the degree of confidence in the prediction results has not been fully discussed in related works. In this article, we propose a similarity confidence coefficient and a confidence measure for link prediction. The former is used to balance the reliability of similarity calculation results, which might be untrustworthy due to the information asymmetry in the calculation, and also makes it easier to achieve the optimal accuracy with a smaller number of neighbors. The latter is used to quantify our confidence in the prediction results of each prediction. The experimental results based on the Movie-Lens data set show that prediction accuracy is improved when the similarity between the nodes is corrected by the similarity confidence coefficient. Second, the experiments also confirm that the confidence degree of the link prediction results can be measured quantitatively. Our research indicates that the confidence level on each prediction is determined by the amount of data used in the corresponding calculation, which can be measured quantitatively.

8.
PLoS Comput Biol ; 11(4): e1004212, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25885453

RESUMO

We uncovered the universal statistical laws for the biomolecular recognition/binding process. We quantified the statistical energy landscapes for binding, from which we can characterize the distributions of the binding free energy (affinity), the equilibrium constants, the kinetics and the specificity by exploring the different ligands binding with a particular receptor. The results of the analytical studies are confirmed by the microscopic flexible docking simulations. The distribution of binding affinity is Gaussian around the mean and becomes exponential near the tail. The equilibrium constants of the binding follow a log-normal distribution around the mean and a power law distribution in the tail. The intrinsic specificity for biomolecular recognition measures the degree of discrimination of native versus non-native binding and the optimization of which becomes the maximization of the ratio of the free energy gap between the native state and the average of non-native states versus the roughness measured by the variance of the free energy landscape around its mean. The intrinsic specificity obeys a Gaussian distribution near the mean and an exponential distribution near the tail. Furthermore, the kinetics of binding follows a log-normal distribution near the mean and a power law distribution at the tail. Our study provides new insights into the statistical nature of thermodynamics, kinetics and function from different ligands binding with a specific receptor or equivalently specific ligand binding with different receptors. The elucidation of distributions of the kinetics and free energy has guiding roles in studying biomolecular recognition and function through small-molecule evolution and chemical genetics.


Assuntos
Cinética , Ligantes , Modelos Teóricos , Ligação Proteica/fisiologia , Biologia Computacional , Distribuições Estatísticas , Termodinâmica
9.
Phys Chem Chem Phys ; 18(12): 8570-8, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26947972

RESUMO

We investigated the main universal statistical distributions of single molecular recognition. The distributions of the single molecule binding free energy spectrum or density of states were characterized in the ligand-receptor binding energy landscape. The analytical results are consistent with the microscopic molecular simulations. The free energy distribution of different binding modes or states for a single molecule ligand receptor pair is approximately Gaussian near the mean and exponential at the tail. The equilibrium constant of single molecule binding is log-normal distributed near the mean and power law distributed near the tail. Additionally, we found that the kinetics distribution of single molecule ligand binding can be characterized by log-normal around the mean and power law distribution near the tail. This distribution is caused by exploration of the underlying inhomogeneous free energy landscape. Different ligand-receptor binding complexes have the same universal form of distribution but differ in parameters.

10.
Hortic Res ; 11(3): uhae033, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38495030

RESUMO

Chinese bayberry (Myrica rubra or Morella rubra; 2n = 16) produces fruit with a distinctive flavor, high nutritional, and economic value. However, previous versions of the bayberry genome lack sequence continuity. Moreover, to date, no large-scale germplasm resource association analysis has examined the allelic and genetic variations determining fruit quality traits. Therefore, in this study, we assembled a telomere-to-telomere (T2T) gap-free reference genome for the cultivar 'Zaojia' using PacBio HiFi long reads. The resulting 292.60 Mb T2T genome, revealed 8 centromeric regions, 15 telomeres, and 28 345 genes. This represents a substantial improvement in the genome continuity and integrity of Chinese bayberry. Subsequently, we re-sequenced 173 accessions, identifying 6 649 674 single nucleotide polymorphisms (SNPs). Further, the phenotypic analyses of 29 fruit quality-related traits enabled a genome-wide association study (GWAS), which identified 1937 SNPs and 1039 genes significantly associated with 28 traits. An SNP cluster pertinent to fruit color was identified on Chr6: 3407532 to 5 153 151 bp region, harboring two MYB genes (MrChr6G07650 and MrChr6G07660), exhibiting differential expression in extreme phenotype transcriptomes, linked to anthocyanin synthesis. An adjacent, closely linked gene, MrChr6G07670 (MLP-like protein), harbored an exonic missense variant and was shown to increase anthocyanin production in tobacco leaves tenfold. This SNP cluster, potentially a quantitative trait locus (QTL), collectively regulates bayberry fruit color. In conclusion, our study presented a complete reference genome, uncovered a suite of allelic variations related to fruit-quality traits, and identified functional genes that could be harnessed to enhance fruit quality and breeding efficiency of bayberries.

11.
Environ Sci Pollut Res Int ; 31(4): 5500-5512, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38123780

RESUMO

Carbendazim (CBZ) and prochloraz (PCZ) are broad-spectrum fungicides used in agricultural peat control. Both fungicides leave large amounts of residues in fruits and are toxic to non-target organisms. However, the combined toxicity of the fungicides to non-target organisms is still unknown. Therefore, we characterized the toxic effects of dietary supplementation with CBZ, PCZ, and their combination for 90 days in 6-week-old male Institute of Cancer Research (ICR) mice. CBZ-H (100 mg/kg day), PCZ-H (10 mg/kg day), and their combination treatments increased the relative liver weights and caused liver injury. The serum total cholesterol (TC), triglyceride (TG), glucose (Glu), pyruvate (PYR), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels were reduced, and synergistic toxicity was observed. Hepatic transcriptome revealed that 326 differentially expressed genes (DEGs) of liver were observed in the CBZ treatment group, 149 DEGs in the PCZ treatment group, and 272 DEGs in the combination treatment group. According to KEGG enrichment analysis, the fungicides and their combination affected lipid metabolism, amino acid metabolism, and ferroptosis. In addition, the relative mRNA levels of key genes involved in lipid metabolism were also examined. Compared with individual exposure, combined exposure to CBZ and PCZ caused a more obvious decrease in the expression of some genes related to glycolipid metabolism. Furthermore, the relative mRNA levels of some key genes in the combination treatment group were lower than those in the CBZ and PCZ treated groups. In summary, CBZ, PCZ, and their combination generally caused hepatotoxicity and glycolipid metabolism disorders, which could provide new insights for investigating the combined toxicity of multiple fungicides to animals.


Assuntos
Benzimidazóis , Carbamatos , Fungicidas Industriais , Imidazóis , Camundongos , Masculino , Animais , Fungicidas Industriais/farmacologia , Fígado , Perfilação da Expressão Gênica , LDL-Colesterol/metabolismo , Glicolipídeos/metabolismo , RNA Mensageiro/metabolismo
12.
Front Plant Sci ; 14: 1127228, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36818844

RESUMO

Chinese bayberry (Myrica rubra) is an important tree in South China, with its fruit being of nutritional and high economic value. In this study, early ripening (ZJ), medium ripening (BQ) and late ripening (DK) varieties were used as test materials. Young leaves of ZJ, BQ and DK in the floral bud morphological differentiation periods were selected for transcriptome sequencing to excavate earliness related genes. A total of 4,538 differentially expressed genes were detected. Based on clustering analysis and comparisons with genes reportedly related to flowering in Arabidopsis thaliana, 25 homologous genes were identified. Of these, one gene named MrSPL4 was determined, with its expression down-regulated in DK but up-regulated in ZJ and BQ. MrSPL4 contained SBP domain and the target site of miR156, and its total and CDS length were 1,664 bp and 555 bp respectively. The overexpression vector of MrSPL4 (35S::35S::MrSPL4-pCambia2301-KY) was further constructed and successfully transfected into tobacco to obtain MrSPL4-positive plants. Based on the results of qRT-PCR, the relative expression of MrSPL4 was up regulated by 3,862.0-5,938.4 times. Additionally, the height of MrSPL4-positive plants was also significantly higher than that of wild-type (WT), with the bud stage occurring 12 days earlier. Altogether, this study identified an important gene -MrSPL4 in Chinese bayberry, which enhanced growth and flowering, which provided important theoretical basis for early-mature breeding of Chinese bayberry.

13.
Nat Commun ; 14(1): 5594, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37696805

RESUMO

Single-atom catalysts (SACs) have become one of the most attractive frontier research fields in catalysis and energy conversion. However, due to the atomic heterogeneity of SACs and limitations of ensemble-averaged measurements, the essential active sites responsible for governing specific catalytic properties and mechanisms remain largely concealed. In this study, we develop a quantitative method of single-atom catalysis-fluorescence correlation spectroscopy (SAC-FCS), leveraging the atomic structure-dependent catalysis kinetics and single-turnover resolution of single-molecule fluorescence microscopy. This method enables us to investigate the oxidase-like single-molecule catalysis on unidentical iron-nitrogen (Fe-N) coordinated SACs, quantifying the active sites and their kinetic parameters. The findings reveal the significant differences of single sites from the average behaviors and corroborate the oxidase-like catalytic mechanism of the Fe-N active sites. We anticipate that the method will give essential insights into the rational design and application of SACs.

14.
Antioxidants (Basel) ; 13(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38247485

RESUMO

Twig blight disease is the primary disease that affects the production of Myrica rubra in China. It was reported that exogenous brassinolide (BL) can improve disease resistance in plants. Here, we examined the effects of exogenous BL on disease resistance, chlorophyll contents, antioxidant enzyme activity, ROS accumulation, and key gene expression of M. rubra to analyze the mechanism of BR-induced resistance of twig blight disease in M. rubra. The results demonstrated that 2.0 mg·L-1 of BL could significantly lessen the severity of twig blight disease in M. rubra. Exogenous BL increased the contents of chlorophyll a, chlorophyll b, carotenoids, and total chlorophyll. Moreover, exogenous BL also significantly enhanced the activity of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and decreased malondialdehyde (MDA) content and reactive oxygen species (ROS) accumulation in leaves, such as H2O2 and O2·-. Additionally, exogenous BL dramatically up-regulated the expression of pathogenesis-related (PR) genes such as MrPR1, MrPR2, and MrPR10, as well as important genes such as MrBAK1, MrBRI1, and MrBZR1 involved in brassinosteroid (BR) signaling pathway. The transcriptome analysis revealed that a total of 730 common differentially expressed genes (DEGs) under BL treatment were found, and these DEGs were primarily enriched in four Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Based on these findings, nine important candidate genes related to the resistance of twig blight disease under BL treatment were further identified. In this study, we elucidated the effects of exogenous BL on enhancing the resistance of M. rubra to twig blight disease and preliminary analyzed the potential mechanism of resistance induction, which will provide a crucial foundation for the management and prevention of twig blight disease in M. rubra.

15.
Food Sci Nutr ; 11(1): 493-503, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36655066

RESUMO

The alcohol extracts of Chinese bayberry (Myrica rubra) branches (MRBE) are rich in flavonoids which have a variety of medicinal benefits, but their effects on human HepG2 were unknown. In this study, the effects of MRBE on HepG2 cell growth and its potential for inhibiting cancer were explored. The results displayed that MRBE inhibited HepG2 proliferation both by arresting cells in S phase and promoting apoptosis. Quantitative reverse-transcription PCR (qRT-PCR), western blotting, and immunofluorescence showed that MRBE induced S-phase arrest by upregulating p21, which in turn downregulated cyclin and cyclin-dependent kinase messenger RNA (mRNA) and protein. Apoptosis was induced by blocking the expression of BCL-2 and suppression of the Raf/ERK1 signaling pathways. These results indicated that MRBE may have the potential for treatment of human liver cancer, highlighting novel approaches for developing new pharmacological tools for the treatment of this deadly type cancer. Meanwhile, it provides a new direction for the medicinal added values of Chinese bayberry, which helped to broaden the diversified development of its industry chain.

16.
Bioinformatics ; 27(3): 399-404, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21148544

RESUMO

MOTIVATION: Biofuel cells (BFCs) based on enzymes and microbes are the promising future alternative sources of sustainable electrical energy under mild conditions (i.e. ambient temperature and neutral pH). By combining the adaptive behavior of BFCs self-regulating energy release with the versatility of biocomputing, we construct a novel gas-controlled biocomputing security system, which could be used as the potential implantable self-powered and 'smart' medical system with the logic diagnosis aim. RESULTS: We have demonstrated a biocomputing security system based on BFCs. Due to the unique 'RESET' reagent of N(2) applied in this work, the prepared biocomputing security system can be reset and cycled for a large number of times with no 'RESET' reagent-based 'waste'. This would be advantageous for the potential practical applications of such keypad lock as well as the development of biocomputing security devices. In order to validate the universality of the system and also to harvest energy directly from biofuels with enhanced power output, we replace the glucose with orange juice as the biofuel to operate BFCs-based biocomputing system, which also possesses the function of keypad lock. In addition, by introducing BFCs into the biocomputing security system, the adaptive behavior of the BFCs self-regulating the power release would be an immense advantage of such security keypad lock devices in potential self-powered implantable medical systems. The designed sequence gives the maximum power output and discriminate itself from the rest of the sequences. From this, we find that maximizing the dimensionless ratio of gap versus SD of the power output spectrum (a funnel in power outputs) gives the quantitative optimal design criterion. Therefore, our construction here may also provide a practical example and microscopic structural basis for mimicking the real biological network systems and bridge the gaps between the theoretical concepts and experiments important for biomolecular systems and synthetic biology.


Assuntos
Fontes de Energia Bioelétrica , Biocombustíveis , Computadores Moleculares/normas , Gases , Eletrodos , Glucose/química , Concentração de Íons de Hidrogênio , Lógica , Biologia Sintética
17.
Nat Commun ; 13(1): 2808, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606351

RESUMO

Hydrogen peroxide has been synthesized mainly through the electrocatalytic and photocatalytic oxygen reduction reaction in recent years. Herein, we synthesize a single-atom rhodium catalyst (Rh1/NC) to mimic the properties of flavoenzymes for the synthesis of hydrogen peroxide under mild conditions. Rh1/NC dehydrogenates various substrates and catalyzes the reduction of oxygen to hydrogen peroxide. The maximum hydrogen peroxide production rate is 0.48 mol gcatalyst-1 h-1 in the phosphorous acid aerobic oxidation reaction. We find that the selectivity of oxygen reduction to hydrogen peroxide can reach 100%. This is because a single catalytic site of Rh1/NC can only catalyze the removal of two electrons per substrate molecule; thus, the subsequent oxygen can only obtain two electrons to reduce to hydrogen peroxide through the typical two-electron pathway. Similarly, due to the restriction of substrate dehydrogenation, the hydrogen peroxide selectivity in commercial Pt/C-catalyzed enzymatic reactions can be found to reach 75%, which is 30 times higher than that in electrocatalytic oxygen reduction reactions.

18.
PeerJ ; 10: e13070, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35265403

RESUMO

Chinese bayberry (CB) is among the most popular and valuable fruits in China owing to its attractive color and unique sweet/sour taste. Recent studies have highlighted the nutritional value and health-related benefits of CB. CB has special biological characteristics of evergreen, special aroma, dioecious, nodulation, nitrogen fixation. Moreover, the fruits, leaves, and bark of CB plants harbor a number of bioactive compounds including proanthocyanidins, flavonoids, vitamin C, phenolic acids, and anthocyanins that have been linked to the anti-cancer, anti-oxidant, anti-inflammatory, anti-obesity, anti-diabetic, and neuroprotective properties and to the treatment of cardiovascular and cerebrovascular diseases. The CB fruits have been used to produce a range of products: beverages, foods, and washing supplies. Future CB-related product development is thus expected to further leverage the health-promoting potential of this valuable ecological resource. The present review provides an overview of the botanical characteristics, processing, nutritional value, health-related properties, and applications of CB in order to provide a foundation for further research and development.


Assuntos
Antocianinas , Myrica , Humanos , Antocianinas/análise , População do Leste Asiático , Flavonoides , Antioxidantes , Valor Nutritivo
19.
Natl Sci Rev ; 9(3): nwab186, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35261777

RESUMO

Designing highly active nanozymes for various enzymatic reactions remains a challenge in practical applications and fundamental research. In this work, by studying the catalytic functions of natural NADH oxidase (NOX), we devised and synthesized a porous carbon-supported cobalt catalyst (Co/C) to mimic NOX. The Co/C can catalyze dehydrogenation of NADH and transfers electrons to O2 to produce H2O2. Density functional theory calculations reveal that the Co/C can catalyze O2 reduction to H2O2 or H2O considerably. The Co/C can also mediate electron transfer from NADH to heme protein cytochrome c, thereby exhibiting cytochrome c reductase-like activity. The Co/C nanoparticles can deplete NADH in cancer cells, induce increase of the reactive oxygen species, lead to impairment of oxidative phosphorylation and decrease in mitochondrial membrane potential, and cause ATP production to be damaged. This 'domino effect' facilitates the cell to approach apoptosis.

20.
Am J Bot ; 98(4): e93-5, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21613157

RESUMO

PREMISE OF THE STUDY: Microsatellite markers were developed in Myrica rubra to investigate potential hybridization events within or between M. rubra and its closely related species. METHODS AND RESULTS: Using an ISSR-suppression PCR method, 12 primer pairs were temporarily developed with GSG(GT)(6) as the primer for enriching microsatellite sequences and the genomic DNA of M. rubra cv. 'Heijing' as template. The average allele number per locus was 4.9 within 26 individuals including two species, M. rubra and M. nana. Three pairs of primers produced species-specific alleles, and the other nine showed polymorphisms among 26 accessions. CONCLUSIONS: Results indicated that the ISSR-suppression PCR method is suitable for developing microsatellite markers, especially for this species with little understanding of genomic information. The developed microsatellite markers provide a useful tool for further studies of population structure within or between M. rubra and M. nana or other closely related species.


Assuntos
Alelos , Primers do DNA , DNA de Plantas/análise , Loci Gênicos , Repetições de Microssatélites , Myrica/genética , Polimorfismo Genético , Genoma de Planta , Hibridização Genética , Reação em Cadeia da Polimerase/métodos , Especificidade da Espécie
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