Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 67
Filtrar
1.
Nat Commun ; 15(1): 1628, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388527

RESUMO

Euglena gracilis, a model organism of the eukaryotic supergroup Discoba harbouring also clinically important parasitic species, possesses diverse metabolic strategies and an atypical electron transport chain. While structures of the electron transport chain complexes and supercomplexes of most other eukaryotic clades have been reported, no similar structure is currently available for Discoba, limiting the understandings of its core metabolism and leaving a gap in the evolutionary tree of eukaryotic bioenergetics. Here, we report high-resolution cryo-EM structures of Euglena's respirasome I + III2 + IV and supercomplex III2 + IV2. A previously unreported fatty acid synthesis domain locates on the tip of complex I's peripheral arm, providing a clear picture of its atypical subunit composition identified previously. Individual complexes are re-arranged in the respirasome to adapt to the non-uniform membrane curvature of the discoidal cristae. Furthermore, Euglena's conformationally rigid complex I is deactivated by restricting ubiquinone's access to its substrate tunnel. Our findings provide structural insights for therapeutic developments against euglenozoan parasite infections.


Assuntos
Euglena , Membranas Mitocondriais , Transporte de Elétrons , Membranas Mitocondriais/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético
2.
Small ; : e2309031, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38258399

RESUMO

Liposomes are widely used in the biological field due to their good biocompatibility and surface modification properties. With the development of biochemistry and material science, many liposome structures and their surface functional components have been modified and optimized one by one, pushing the liposome platform from traditional to functionalized and intelligent, which will better satisfy and expand the needs of scientific research. However, a main limiting factor effecting the efficiency of liposomes is the complicated environmental conditions in the living body. Currently, in order to overcome the above problem, functionalized liposomes have become a very promising strategy. In this paper, binding strategies of liposomes with four main functional elements, namely nucleic acids, antibodies, peptides, and stimuli-responsive motif have been summarized for the first time. In addition, based on the construction characteristics of functionalized liposomes, such as drug-carrying, targeting, long-circulating, and stimulus-responsive properties, a comprehensive overview of their features and respective research progress are presented. Finally, the paper critically presents the limitations of these functionalized liposomes in the current applications and also prospectively suggests the future development directions, aiming to accelerate realization of their industrialization.

3.
Small ; : e2307995, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212277

RESUMO

A simple, reliable method for identifying ß-lactoglobulin (ß-LG) in dairy products is needed to protect those with ß-LG allergies. A common, practical strategy for target detection is designing simplified nucleic acid nanodevices by integrating functional components. This work presents a label-free modular ß-LG aptasensor consisting of an aptamer-loop G-quadruplex (G4), the working conformation of which is regulated by conformational antagonism to ensure respective module functionality and the related signal transduction. The polymorphic conformations of the module-fused sequence are systematically characterized, and the cause is revealed as shifting antagonistic equilibrium. Combined with conformational folding dynamics, this helped regulate functional conformations by fine-tuning the sequences. Furthermore, the principle of specific ß-LG detection by parallel G4 topology is examined as binding on the G4 aptamer loop by ß-LG to reinforce the G4 topology and fluorescence. Finally, a label-free, assembly-free, succinct, and turn-on fluorescent aptasensor is established, achieving excellent sensitivity across five orders of magnitude, rapidly detecting ß-LG within 22-min. This study provides a generalizable approach for the conformational regulation of module-fused G4 sequences and a reference model for creating simplified sensing devices for a variety of targets.

4.
Anal Methods ; 15(48): 6643-6647, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38044886

RESUMO

Combining powerful adsorption capacity, simple preparation, rapid separation as well as superior stability and recyclability, a polyurea-magnetic hierarchical porous composite has been prepared. It demonstrates efficient physisorption for anionic metabolites in less than one minute and is promising for application to the analysis of a broad range of anionic metabolites in complex matrices.

5.
Adv Sci (Weinh) ; 10(32): e2303375, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37759400

RESUMO

Disuse osteoporosis is characterized by decreased bone mass caused by abnormal mechanical stimulation of bone. Piezo1 is a major mechanosensitive ion channel in bone homeostasis. However, whether intervening in the action of Piezo1 can rescue disuse osteoporosis remains unresolved. In this study, a commonly-used hindlimb-unloading model is employed to simulate microgravity. By single-cell RNA sequencing, bone marrow-derived mesenchymal stem cells (BMSCs) are the most downregulated cell cluster, and coincidentally, Piezo1 expression is mostly enriched in those cells, and is substantially downregulated by unloading. Importantly, activation of Piezo1 by systemically-introducing yoda1 mimics the effects of mechanical stimulation and thus ameliorates bone loss under simulated microgravity. Mechanistically, Piezo1 activation promotes the proliferation and osteogenic differentiation of Gli1+ BMSCs by activating the ß-catenin and its target gene activating transcription factor 4 (ATF4). Inhibiting ß-catenin expression substantially attenuates the effect of yoda1 on bone loss, possibly due to inhibited proliferation and osteogenic differentiation capability of Gli1+ BMSCs mediated by ATF4. Lastly, Piezo1 activation also slightly alleviates the osteoporosis of OVX and aged mice. In conclusion, impaired function of Piezo1 in BMSCs leads to insufficient bone formation especially caused by abnormal mechanical stimuli, and is thus a potential therapeutic target for osteoporosis.


Assuntos
Osteoporose , Ausência de Peso , Animais , Camundongos , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/farmacologia , beta Catenina/genética , Canais Iônicos/farmacologia , Canais Iônicos/uso terapêutico , Osteogênese , Osteoporose/etiologia , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína GLI1 em Dedos de Zinco/farmacologia , Proteína GLI1 em Dedos de Zinco/uso terapêutico
7.
Biotechnol Lett ; 45(8): 955-966, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37266879

RESUMO

Clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9) system has been widely used in gene editing of various organisms. However, food-grade gene editing systems in lactic acid bacteria are still preliminary. Red/ET-dependent homologous recombination or CRISPR-based systems have been developed to gene editing in Lactococcus lactis, but these methods are overall inefficient. In the present study, a recombinant system based on CRISPR/Cas9 technology combined with Red/ET was developed using the plasmid pMG36e derived from Lactococcus lactis. Then, the developed recombinant system was applied to Lactococcus lactis. Knockout efficiency was significantly higher using the developed system (91%). In addition, this system showed the potential to be used as a high-throughput method for hierarchical screening. Finally, a gene-edited strain was obtained, and no antibiotics or exogenous genes were introduced using the developed gene editing system. Thus, the efficient system in lactic acid bacteria was constructed and optimized.


Assuntos
Edição de Genes , Lactococcus lactis , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Plasmídeos/genética , Recombinação Homóloga
8.
Anal Chem ; 95(25): 9539-9547, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37318774

RESUMO

Amino metabolites are essential for life activities and can be used clinically as biomarkers for disease diagnosis and treatment. Solid-phase-supported chemoselective probes can simplify sample handling and enhance detection sensitivity. However, the low efficiency and complicated preparation of traditional probes limit their further application. In this work, a novel solid-phase-supported probe Fe3O4-SiO2-polymers-phenyl isothiocyanate (FSP-PITC) was developed by immobilizing phenyl isothiocyanate on magnetic beads with disulfide as an orthogonal cleavage site, which can couple amino metabolites directly regardless of whether proteins and other matrixes were removed. After purification, the targeted metabolites were released by dithiothreitol and detected by high-resolution mass spectrometry. The simplified processing steps shorten the analysis time, and the introduction of polymers results in a 100-1000-fold increase in probe capacity. With high stability and specificity, FSP-PITC pretreatment allows accurate qualitative and quantitative (R2 > 0.99) analysis, facilitating the detection of metabolites in subfemtomole quantities. Using this strategy, 4158 metabolite signals were detected in negative ion mode. Among them, 352 amino metabolites including human cells (226), serum (227), and mouse samples (274) were searched from the Human Metabolome Database. These metabolites participate in metabolic pathways of amino acids, biogenic amine, and the urea cycle. All these results indicate that FSP-PITC is a promising probe for novel metabolite discovery and high-throughput screening.


Assuntos
Metaboloma , Dióxido de Silício , Humanos , Animais , Camundongos , Espectrometria de Massas/métodos , Aminas Biogênicas , Metabolômica/métodos
9.
Int J Biol Macromol ; 242(Pt 1): 124682, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37164133

RESUMO

Glycoalkaloids (GAs), including α-solanine and α-chaconine, are secondary metabolites found in potato, which are toxic to higher animals. In a previous study, Alkalihalobacillus clausii PA21 showed the capacity to degrade GAs. Herein, the transcriptome response of PA21 to α-solanine or α-chaconine was evaluated. In total, 3170 and 2783 differential expressed genes (DEGs) were found in α-solanine- and α-chaconine-treated groups, respectively, with most DEGs upregulated. Moreover, GAs activated transmembrane transport, carbohydrate metabolism, transcription, quorum sensing, and bacterial chemotaxis in PA21 to withstand GA-induced stress and promote GAs degradation. Furthermore, qRT-PCR analysis confirmed the upregulation of degrading enzymes and components involved in GA degradation in PA21. In addition, the GAs-degrading enzymes were heterologous expressed, purified, and incubated with GAs to analyze the degradation products. The results showed that α-solanine was degraded to ß1-solanine, ß2-solanine, γ-solanine, and solanidine by ß-glucosidase, α-rhamnosidase, and ß-galactosidase. Meanwhile, α-chaconine was degraded to ß1-chaconine, ß2-chaconine, γ-chaconine, and solanidine by ß-glucosidase and α-rhamnosidase. Overall, the molecular mechanism underlying GAs degradation by PA21 was revealed by RNAseq combined with protein expression and function studies, thus providing the basis for the development of engineered bacteria that can efficiently degrade GAs to promote their application in the control of GAs in potatoes.


Assuntos
Celulases , Solanina , Solanum tuberosum , Animais , Solanina/análise , Solanina/metabolismo , Solanina/farmacologia , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Bactérias/metabolismo , Perfilação da Expressão Gênica , Redes e Vias Metabólicas , Celulases/metabolismo
10.
Nat Commun ; 14(1): 2542, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-37248254

RESUMO

Tetrahymena thermophila, a classic ciliate model organism, has been shown to possess tubular mitochondrial cristae and highly divergent electron transport chain involving four transmembrane protein complexes (I-IV). Here we report cryo-EM structures of its ~8 MDa megacomplex IV2 + (I + III2 + II)2, as well as a ~ 10.6 MDa megacomplex (IV2 + I + III2 + II)2 at lower resolution. In megacomplex IV2 + (I + III2 + II)2, each CIV2 protomer associates one copy of supercomplex I + III2 and one copy of CII, forming a half ring-shaped architecture that adapts to the membrane curvature of mitochondrial cristae. Megacomplex (IV2 + I + III2 + II)2 defines the relative position between neighbouring half rings and maintains the proximity between CIV2 and CIII2 cytochrome c binding sites. Our findings expand the current understanding of divergence in eukaryotic electron transport chain organization and how it is related to mitochondrial morphology.


Assuntos
Tetrahymena thermophila , Tetrahymena thermophila/genética , Membranas Mitocondriais/metabolismo , Mitocôndrias/metabolismo
11.
Int Orthop ; 47(7): 1715-1727, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37074375

RESUMO

PURPOSE: The study aimed to compare the perioperative complications, short-term clinical outcomes, patient-reported outcomes, and radiographic parameters of tibiofibular proximal osteotomy combined with absorbable spacer insertion (TPOASI) and open-wedge high tibial osteotomy (OWHTO) in a two year postoperative time period. METHODS: A total of 160 patients with Kellgren-Lawrence classification grade 3 medial compartmental knee OA were randomized to receive either TPOASI (n = 82) or OWHTO (n = 78). The primary and secondary outcomes were measured preoperatively, postoperatively, and at each follow-up examination. The primary outcomes were the between-group change in the Western Ontario and McMaster Universities Global score (WOMAC). Secondary measures included visual analog scale (VAS), radiographic parameters, American Knee Society Score (KSS), operation time, blood loss, length of incision, hospital stay, and relevant complications. Postoperative radiographic parameters, including the femorotibial angle (FTA), varus angle (VA), and joint line convergence angle (JLCA), were measured to evaluate the correction of varus deformity. RESULTS: No significant differences were found in the baseline data between the two groups. Both methods improved functional status and pain postoperatively. For primary outcomes of both groups, statistical difference was observed in WOMAC scores at the 6-month follow-up (P < 0.001). For secondary outcomes, no statistical difference was observed between the groups during the 2-year follow-up (P > 0.05). For TPOASI vs. OWHTO, the mean hospital stay (6.6 ± 1.3 days vs. 7.8 ± 2.1 days) was shorter (P < 0.001), and both blood loss (70.56 ± 35.58 vs. 174.00 ± 66.33 mL) and complication rate (3.7% vs. 12.8%) were significantly lower (P < 0.005 for both). CONCLUSIONS: Both approaches showed satisfactory functional outcomes and alleviated pain. However, TPOASI is a simple, feasible method with few complications, and it could be widely used.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/cirurgia , Tíbia/cirurgia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteotomia/efeitos adversos , Osteotomia/métodos , Dor , Estudos Retrospectivos
12.
Food Funct ; 14(7): 3304-3318, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36938927

RESUMO

The prevention, mitigation and treatment of depression has become a global issue that needs to be solved urgently. Sayram Ketteki, a traditional natural fermented yoghurt from the region with the world's fourth highest life expectancy, has been known as the "longevity secret", whose longevity and anti-depression factors are speculated to come from its rich microorganisms. Therefore, for the first time, we systematically studied in depth the microbes of Sayram Ketteki, screened a new edible probiotic strain, Lactiplantibacillus plantarum R6-3, and explored its anti-depression effect in chronic unpredictable mild stress (CUMS)-induced depression in mice. It is encouraging that L. plantarum R6-3 was significantly superior to the classic anti-depressant drug, fluoxetine, in the performance of promoting sucrose preference test (SPT) behavior by 18% (p < 0.001), lowering the serum CORT content by 5.6% (p < 0.05), accelerating the brain-derived neurotrophic factor (BDNF) level by 5.9% (p < 0.01), increasing the serum IL-10 concentration by 2.3% (p < 0.05), up-regulating the expression of BDNF and phosphorylated-ERK by 74% (p < 0.01) and 45% (p < 0.001), respectively, and facilitating the secretion of fecal short-chain fatty acids (SCFAs), including n-butyric, n-valeric, and isovaleric acid by 47% (p < 0.01), 42% (p < 0.05) and 38% (p < 0.05), respectively. Through the microbiota-gut-brain axis, L. plantarum R6-3 promoted the secretion of intestinal SCFAs through regulation of the composition and function of the gut microbiota, and activated the production of the monoamine neurotransmitter, renewed the level of brain neurotrophic factor, and suppressed the hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis by adjusting the hippocampal BDNF/TrkB/ERK/CREB signaling pathway, thereby improving the immune and oxidative stress status, protecting hippocampal tissue from damage, maintaining a healthy weight and preventing CUMS-induced depressive behavior in mice. It has great prospects for the development of natural functional foods, the prevention and treatment of depression and in innovative microecological preparations.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Transtorno Depressivo , Camundongos , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Antidepressivos/farmacologia , Eixo Encéfalo-Intestino , Depressão/tratamento farmacológico , Depressão/prevenção & controle , Depressão/metabolismo , Transtorno Depressivo/tratamento farmacológico , Hipocampo/metabolismo , Estresse Psicológico/tratamento farmacológico , Modelos Animais de Doenças
13.
Anal Chim Acta ; 1250: 340977, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36898822

RESUMO

The analysis of biological samples is often affected by the background matrix. Proper sample preparation is a critical step in the analytical procedure for complex samples. In this study, a simple and efficient enrichment strategy based on Amino-functionalized Polymer-Magnetic MicroParticles (NH2-PMMPs) with coral-like porous structures was developed to enable the detection of 320 anionic metabolites, providing detailed coverage of phosphorylation metabolism. Among them, 102 polar phosphate metabolites including nucleotides, cyclic nucleotides, sugar nucleotides, phosphate sugars, and phosphates, were enriched and identified from serum, tissues, and cells. Furthermore, the detection of 34 previously unknown polar phosphate metabolites in serum samples demonstrates the advantages of this efficient enrichment method for mass spectrometric analysis. The limit of detections (LODs) were between 0.02 and 4 nmol/L for most anionic metabolites and its high sensitivity enabled the detection of 36 polar anion metabolites from 10 cell equivalent samples. This study has provided a promising tool for the efficient enrichment and analysis of anionic metabolites in biological samples with high sensitivity and broad coverage, facilitating the knowledge of the phosphorylation processes of life.


Assuntos
Nucleotídeos , Fosfatos , Ânions/química , Ânions/metabolismo , Fenômenos Magnéticos , Espectrometria de Massas/métodos , Nucleosídeos/síntese química , Nucleosídeos/química , Nucleotídeos/síntese química , Nucleotídeos/química , Fosfatos/síntese química , Fosfatos/metabolismo
14.
Plant Cell Physiol ; 63(12): 1890-1899, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35475535

RESUMO

Sinapate esters, which are induced in plants under ultraviolet-B (UV-B) irradiation, have important roles not only in the protection against UV-B irradiation but also in the regulation of stomatal closure. Here, we speculated that sinapate esters would function in the stomatal closure of Arabidopsis thaliana in response to UV-B. We measured the stomatal aperture size of the wild-type (WT) and bright trichomes 1 (brt1) and sinapoylglucose accumulator 1 (sng1) mutants under UV-B irradiation; the latter two mutants are deficient in the conversion of sinapic acid to sinapoylglucose (SG) and SG to sinapoylmalate (SM), respectively. Both the brt1 and sng1 plants showed smaller stomatal apertures than the WT under normal light and UV-B irradiation conditions. The accumulation of SM and malate were induced by UV-B irradiation in WT and brt1 plants but not in sng1 plants. Consistently, exogenous malate application reduced UV-B-induced stomatal closure in WT, brt1 and sng1 plants. Nonetheless, levels of reactive oxygen species (ROS), nitric oxide (NO) and cytosolic Ca2+ were higher in guard cells of the sng1 mutant than in those of the WT under normal white light and UV-B irradiation, suggesting that disturbance of sinapate metabolism induced the accumulation of these signaling molecules that promote stomatal closure. Unexpectedly, exogenous sinapic acid application prevented stomatal closure of WT, brt1 and sng1 plants. In summary, we hypothesize that SG or other sinapate esters may promote the UV-B-induced malate accumulation and stomatal closure, whereas sinapic acid inhibits the ROS-NO pathway that regulates UV-B-induced cytosolic Ca2+ accumulation and stomatal closure.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Peróxido de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Ésteres/metabolismo , Malatos/metabolismo , Cálcio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Estômatos de Plantas/fisiologia , Ácido Abscísico/metabolismo
15.
Plant Cell Physiol ; 63(12): 1900-1913, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35681253

RESUMO

Recent investigations in Arabidopsis thaliana suggest that SUPPRESSOR of MORE AXILLARY GROWTH 2 1 (SMAX1) and SMAX1-LIKE2 (SMXL2) are negative regulators of karrikin (KAR) and strigolactone (SL) signaling during plant growth and development, but their functions in drought resistance and related mechanisms of action remain unclear. To understand the roles and mechanisms of SMAX1 and SMXL2 in drought resistance, we investigated the drought-resistance phenotypes and transcriptome profiles of smax1 smxl2 (s1,2) double-mutant plants in response to drought stress. The s1,2 mutant plants showed enhanced drought-resistance and lower leaf water loss when compared with wild-type (WT) plants. Transcriptome comparison of rosette leaves from the s1,2 mutant and the WT under normal and dehydration conditions suggested that the mechanism related to cuticle formation was involved in drought resistance. This possibility was supported by enhanced cuticle formation in the rosette leaves of the s1,2 mutant. We also found that the s1,2 mutant plants were more sensitive to abscisic acid in assays of stomatal closure, cotyledon opening, chlorophyll degradation and growth inhibition, and they showed a higher reactive oxygen species detoxification capacity than WT plants. In addition, the s1,2 mutant plants had longer root hairs and a higher root-to-shoot ratio than the WT plants, suggesting that the mutant had a greater capacity for water absorption than the WT. Taken together, our results indicate that SMAX1 and SMXL2 negatively regulate drought resistance, and disruption of these KAR- and SL-signaling-related genes may therefore provide a novel means for improving crop drought resistance.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Resistência à Seca , Germinação/genética , Ácido Abscísico/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
16.
J Dairy Sci ; 106(2): 897-911, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36526462

RESUMO

Yogurt and its related products are popular worldwide. During transportation and storage, Lactobacillus delbrueckii ssp. bulgaricus in yogurt continues to metabolize to form lactic acid, the postacidification phenomenon of yogurt. Postacidification of yogurt is a widespread phenomenon in the dairy industry. Many scholars have done research on controlling the postacidification process, but few report on the molecular mechanisms involved. In this study, we used a molecular-assisted approach to screen food additives that can inhibit postacidification and analyzed its effects on yogurt quality as well as its regulatory mechanism from multi-omics perspectives in combination. The copper ion was found to upregulate the expression of the LDB_RS05285 gene, and the copper transporter-related genes were regulated by copper. Based on the metabolic-level analysis, copper was found to promote lactose hydrolysis, accumulate a large amount of glucose and galactose, inhibit the conversion of glucose to lactic acid, and reduce the production of lactic acid. The significantly greater abundance of l-isoleucine and l-phenylalanine increased the abundance of 3-methylbutyraldehyde (∼1.2 times) and benzaldehyde (∼7.9 times) to different degrees, which contributed to the formation of the overall flavor of yogurt. Copper not only stabilizes the acidity of yogurt, but also it improves the flavor of yogurt. Through this established method involving quantitative and correlation analyses at the transcriptional and metabolic levels, this study provides guidance for the research and development of food additives that inhibit postacidification of yogurt and provide a reference for studying the changes of metabolites during storage of yogurt.


Assuntos
Cobre , Lactobacillus delbrueckii , Animais , Fermentação , Cobre/metabolismo , Iogurte/análise , Lactobacillus delbrueckii/metabolismo , Glucose/metabolismo , Óperon , Ácido Láctico/metabolismo , Streptococcus thermophilus/metabolismo
17.
Small ; 19(1): e2204734, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36354199

RESUMO

Playing a great role in human physiologies and pathologies, carbonyl metabolites are intimately associated with a variety of diseases, though the effective analysis method of them remains a challenge. A hydrazide-terminated polyurea-modified magnetic particle (HPMP) with versatile probes is developed to address this issue. The capture ability of HPMPs for carbonyl metabolite is more than 1200 µmol g-1 , which is increased by 4 orders of magnitude via the introduction of polyurea. With a broad linear range of over 4 orders of magnitude, remarkably improved sensitivity, and limit of detection at attomole quantities, HPMPs are applied in relative quantification of more than 1500 carbonyl metabolites in 113 human serum samples with high throughput and high coverage. The combined indicators of these metabolites demonstrates a great diagnostic accuracy for distinguishing between health and disease subjects as well as differentiating the patients with benign lung disease and lung cancer. Combining powerful capture ability, low-cost preparation, and convenient operation, the HPMPs demonstrate extensive application in biomarker discovery and the detailed study of the biochemical landscape.


Assuntos
Neoplasias Pulmonares , Polímeros , Humanos , Neoplasias Pulmonares/metabolismo , Biomarcadores , Fenômenos Magnéticos
18.
Food Res Int ; 162(Pt A): 111929, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461190

RESUMO

The post-acidification of yogurt results in short shelf life, undesirable flavor, and sour taste, making it unacceptable to consumers. Many scholars have proposed several solutions to this problem. However, the existing methods of inhibiting post-acidification cannot fundamentally solve this problem. So exploring the molecular mechanism behind post-acidification can be a better approach to finding the solution. Therefore, we first evaluated the correlation between 69 candidate genes for post-acidification and changes in the acidity of yogurt fermented with different Lactobacillus bulgaricus, and mined a biomarker LDB_RS00370 for post-acidification. Subsequently, this biomarker was used for large-scale screening of food additives that could inhibit post-acidification, and niacin was found to be the most representative one. Finally, the mechanism of niacin inhibiting post-acidification of yogurt was analyzed by RNA-seq, which revealed that post-acidification might be inhibited by affecting protein synthesis and glycolysis. This study opens up a novel perspective on molecular prediction of the post-acidification process, which could provide guidance for precautions to be taken in yogurt production.


Assuntos
Lactobacillus delbrueckii , Niacina , Iogurte , Biomarcadores , Concentração de Íons de Hidrogênio
19.
Food Sci Biotechnol ; 31(11): 1451-1462, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36060571

RESUMO

Lactobacillus plantarum is an essential probiotic in the human gastrointestinal tract. L. plantarum BF_15, a functional probiotic isolated from the feces of breast-fed infants, has been reported in many in vitro and in vivo studies with strong gastrointestinal adaptability and outstanding anti-oxidative activities. Therefore, the whole genome of L. plantarum BF_15 was sequenced. Several genes, encoding the gastrointestinal adaptability-related proteins, were identified, including genes related to gastrointestinal environment-induced stress resistance, adhesive performance, and ability to transport and metabolize resistant starch and oligosaccharides. Genes related to alleviating oxidative stress were also found. Further functional verification was carried out by RT-qPCR on the 10 and 12 key adhesion and antioxidant genes. Overall, this study might provide a critical basis for L. plantarum BF_15 as a potential candidate for probiotics. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01132-w.

20.
Plant Physiol ; 190(4): 2671-2687, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-35822606

RESUMO

The karrikin (KAR) receptor and several related signaling components have been identified by forward genetic screening, but only a few studies have reported on upstream and downstream KAR signaling components and their roles in drought tolerance. Here, we characterized the functions of KAR UPREGULATED F-BOX 1 (KUF1) in drought tolerance using a reverse genetics approach in Arabidopsis (Arabidopsis thaliana). We observed that kuf1 mutant plants were more tolerant to drought stress than wild-type (WT) plants. To clarify the mechanisms by which KUF1 negatively regulates drought tolerance, we performed physiological, transcriptome, and morphological analyses. We found that kuf1 plants limited leaf water loss by reducing stomatal aperture and cuticular permeability. In addition, kuf1 plants showed increased sensitivity of stomatal closure, seed germination, primary root growth, and leaf senescence to abscisic acid (ABA). Genome-wide transcriptome comparisons of kuf1 and WT rosette leaves before and after dehydration showed that the differences in various drought tolerance-related traits were accompanied by differences in the expression of genes associated with stomatal closure (e.g. OPEN STOMATA 1), lipid and fatty acid metabolism (e.g. WAX ESTER SYNTHASE), and ABA responsiveness (e.g. ABA-RESPONSIVE ELEMENT 3). The kuf1 mutant plants had higher root/shoot ratios and root hair densities than WT plants, suggesting that they could absorb more water than WT plants. Together, these results demonstrate that KUF1 negatively regulates drought tolerance by modulating various physiological traits, morphological adjustments, and ABA responses and that the genetic manipulation of KUF1 in crops is a potential means of enhancing their drought tolerance.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Secas , Proteínas de Arabidopsis/metabolismo , Estômatos de Plantas/fisiologia , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Água/metabolismo , Plantas Geneticamente Modificadas/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...