Molecular interaction

分子相互作用
  • 文章类型: Journal Article
    研究了不同含量的秋葵多糖(OP)(0%-1%)对肌原纤维蛋白(MP)凝胶化的影响以及OP与MP之间的相互作用机制。OP以0.75%的添加剂限制改善了MP的胶凝性质。流变学分析表明,OP的加入增强了MPs之间的相互作用,导致更致密的分子间凝胶网络结构。OP的加入改变了傅里叶变换红外光谱的I850/I830,表明OP和MP之间形成了氢键。添加OP促进了MP中从α-螺旋到β-折叠的转变。OP暴露了MPs的疏水基团,并增加了它们之间的疏水相互作用的数量,有利于形成致密的凝胶网络。分子对接预测氢键是参与OP和MP结合的主要力量。中度OP促进了MP的聚集并改善了其功能特性,促进热诱导的凝胶化。
    The effects of various contents of okra polysaccharide (OP) (0%-1%) on myofibrillar protein (MP) gelation and the interaction mechanism between OP and MP were investigated. OP improved the gelling properties of MP with an additive limitation of 0.75%. Rheological analysis demonstrated that the addition of OP enhanced the interactions between MPs, resulting in a denser intermolecular gel network structure. The addition of OP shifted the I850/I830 of Fourier transform infrared spectroscopy, indicating that hydrogen bonds were formed between OP and MP. Adding OP promoted the transition from α-helix to β-sheet in the MP. OP exposed the hydrophobic groups of MPs and increased the number of hydrophobic interactions between them, favoring the formation of a dense gel network. Molecular docking predicted that hydrogen bonds were the main force involved in the binding of OP and MP. Moderate OP promoted the aggregation of MPs and improved their functional properties, facilitating heat-induced gelation.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    熊果苷,一种典型的光学异构体,以其良好的功效和安全性在美白化妆品中获得了广泛的赞誉。然而,α-熊果苷和β-熊果苷渗透皮肤的分子机制尚不清楚。本文旨在揭示α-熊果苷和β-熊果苷如何与角蛋白或SC脂质相互作用,进一步证明了它们与药物渗透性的关系。通过体外渗透测试,我们发现α-熊果苷在猪皮肤中的药物积累明显高于β-熊果苷。此外,α-熊果苷在药物渗透过程中主要诱导酰胺II二级结构的改变,这有利于α-熊果苷的渗透。相反,β-熊果苷对SC脂质的拉伸振动表现出可观察的作用,拥有明显更强的混合能量,结合能和与神经酰胺(Cer)的相容性比α-熊果苷,这最终限制了它的渗透。有趣的是,SC脂质的游离脂肪酸和神经酰胺专门利用其羧基的氧原子来对接熊果苷分子,增强它们与β-熊果苷的亲和力,通过分子模拟和13碳核磁共振证实。然而,观察到α-熊果苷和角蛋白之间的良好相容性。强调熊果苷独特的空间构型和相反的旋光度是影响熊果苷与SC之间分子间力的主要因素。从而导致不同的药物渗透。在细胞和体内皮肤药代动力学研究中,α-熊果苷还具有比β-熊果苷更高的细胞摄取和局部生物利用度。这项研究揭示了光学异构体熊果苷在分子水平上的经皮渗透机制,为研究具有相似空间构型的其他异构体的渗透行为提供方法参考。
    Arbutin, a typical optical isomer, has garnered widespread acclaim in the whitening cosmetics for its favorable efficacy and safety. However, the molecular mechanisms underlying α-arbutin and β-arbutin permeating across the skin have not elucidated clearly yet. Herein we aimed to unveil how α-arbutin and β-arbutin interacted with keratin or SC lipids, further demonstrating the relationship with their drug permeability. We found that α-arbutin displayed significantly higher drug accumulation into the porcine skin than β-arbutin within 24 h through in vitro permeation test. Moreover, α-arbutin predominantly induced the alternations of secondary structure of amide II during the drug permeation, which was favorable for α-arbutin permeation. On the contrary, β-arbutin exhibited an observable effect on the stretching vibration of SC lipids, possessing a significantly stronger mixing energy, binding energy and compatibility with ceramide (Cer) than that of α-arbutin, which ultimately restricted its permeation. Interestingly, free fatty acids and ceramides of the SC lipids specifically utilized its oxygen atom of carboxyl group to dock the arbutin molecules, enhancing their affinity with β-arbutin, as confirmed by molecular simulation and 13Carbon Nuclear Magnetic Resonance. Nevertheless, a favorable compatibility between α-arbutin and keratin was observed. It was emphasized that the distinct spatial configuration and opposite optical rotation of arbutin was the leading factor affecting the intermolecular force between arbutin and the SC, thereby resulting in a diverse drug permeation. In cellular and in vivo skin pharmacokinetic studies, α-arbutin also possessed a higher cellular uptake and topical bioavailability than β-arbutin. This study revealed the transdermal permeation mechanisms of optical isomer arbutin at the molecular levels, providing methodological reference for the investigations of permeation behaviors of other isomers with similar spatial configuration.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    开发高地大麦产品是复杂的,可能是由于高原大麦中存在β-葡聚糖。本研究旨在探讨β-葡聚糖对其理化性质的影响,微观结构,以及高原大麦淀粉(HBS)在糊化和老化过程中的分子相互作用。增加β-葡聚糖含量显著降低峰粘度,挫折粘度,和分解粘度,指示改变的糊化行为。β-葡聚糖含量的增加导致峰值粘度的显著下降。添加20%的β-葡聚糖,它减少了883mPa·s,近38%。流变分析表明,从固体状的质地或质量转变为液体状的质地或质量,最终导致剪切稀化行为。傅里叶变换红外光谱(FT-IR)和X射线衍射(XRD)证实了HBS与β-葡聚糖之间通过分子间氢键相互作用,促进淀粉中双螺旋结构的形成。这些发现提供了一个更深入的了解β-葡聚糖的作用在加工的高原大麦,强调其对淀粉性质的影响。
    Developing highland barley products is complex, possibly due to the presence of β-glucan in highland barley. This study aims to investigate the impact of β-glucan on the physicochemical properties, microstructure, and molecular interactions of highland barley starch (HBS) during gelatinization and aging. Increasing the β-glucan content significantly reduced peak viscosity, setback viscosity, and breakdown viscosity, indicating altered gelatinization behavior. The β-glucan content increase caused a significant drop in peak viscosity. With 20% β-glucan addition, it reduced by 883 mPa·s, nearly 38%. Rheological analysis showed a transition from a solid-like to a liquid-like texture or quality, ultimately leading to a shear-thinning behavior. Fourier-transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) confirmed the interaction between HBS and β-glucan via intermolecular hydrogen bonding, promoting the formation of double helical structures in starch. These findings provide a deeper understanding of the role of β-glucan in the processing of highland barley, highlighting its influence on the starch\'s properties.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    热带和亚热带地区每年面临数百万人死于蚊子传播的疾病。杀虫剂可以预防传播,但会带来健康风险,如皮炎和过敏。主要目标是减轻对合成杀虫剂的反复依赖,从而遏制了蚊子抗性的发展。从Mayurbhanj收集了花cymbogonflexuosus(柠檬草)的叶子,印度,已处理,然后通过蒸汽蒸馏提取精油并进行光谱分析。在不同浓度下进行杀幼虫试验,揭示了花cymbogonflexuosus提取物对斯蒂芬氏按蚊幼虫的显着死亡率。通过使用G蛋白偶联受体(GPCR)序列模拟3D结构,并验证了结构稳定性。在对接后,从具有β-柠檬醛复合物的GPCR蛋白测定结合自由能。分子动力学(MD)研究是在对接的姿势上进行的,该姿势显示出最佳的相互作用谱。第12小时和第24小时的杀幼虫测定显示最高的LC50(致死浓度)为23.493ppm和19.664ppm。β-柠檬醛具有高结合亲和力和可识别的结合位点,这表明它可能通过与它建立稳定的复合物来调节受体的功能。柠檬草油中的β-柠檬醛具有潜在的杀幼虫活性,可有效对抗蚊子的GPCR家族1,并可高效驱避剂抵抗蚊子传播的疾病。
    Tropical and subtropical regions face millions of deaths from mosquito-borne illnesses yearly. Insecticides prevent transmission but pose health risks like dermatitis and allergies. The primary objective was to mitigate the recurring dependence on synthetic insecticides, thereby curbing the development of mosquito resistance. Leaves of Cymbopogon flexuosus (lemongrass) was collected from Mayurbhanj, India, processed, then extracted by steam distillation for essential oils & analyzed spectroscopically. Larvicidal assays were performed across varying concentrations, revealing the significant mortality induced by the Cymbopogon flexuosus extract against Anopheles stephensi larvae. 3D structure was modelled by using G protein-coupled receptors (GPCR) sequence and structural stability was also validated. After docking the binding free energy was determined from GPCR protein with β-citral complex. Molecular dynamics (MD) study was conducted on the docked pose that displayed an optimal interactome profile. The larvicidal assay at the 12th and 24th hour revealed the highest LC50 (lethal concentration) of 23.493 ppm and 19.664 ppm . β-Citral has a high binding affinity and an identifiable binding site, which suggests that it may play a larvicidal role in regulating the receptor\'s function by creating stable complexes with it. β-Citral from lemongrass oils has potential larvicidal activity and effective against GPCR family 1 of mosquito and highly effective repellents against mosquito-borne diseases.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    绿茶的收敛性是单个茶成分的协同和拮抗作用的综合结果,其机制非常复杂,尚未完全理解。在这里,我们使用表没食子儿茶素没食子酸酯(EGCG)/咖啡因(CAF)/唾液模型来模拟饮茶过程中的口腔条件。首先使用分子对接和等温滴定量热法(ITC)研究了CAF对EGCG和唾液蛋白之间相互作用的影响。然后,研究了唾液的流变学特性和微网络结构,以将分子相互作用和感知的收敛性联系起来。结果表明,CAF部分占据了EGCG与唾液蛋白的结合位点,抑制它们的相互作用并引起唾液膜弹性网络结构的变化,从而减少收敛性。
    The astringency of green tea is an integrated result of the synergic and antagonistic effects of individual tea components, whose mechanism is highly complex and not completely understood. Herein, we used an epigallocatechin gallate (EGCG)/caffeine (CAF)/saliva model to simulate the oral conditions during tea drinking. The effect of CAF on the interaction between EGCG and salivary proteins was first investigated using molecular docking and isothermal titration calorimetry (ITC). Then, the rheological properties and the micro-network structure of saliva were studied to relate the molecular interactions and perceived astringency. The results revealed that CAF partially occupied the binding sites of EGCG to salivary proteins, inhibiting their interaction and causing changes in the elastic network structure of the salivary film, thereby reducing astringency.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    PU.1(SPI1)在造血中至关重要,然而,其在人内皮-造血细胞转化(EHT)中的作用尚不清楚.比较人体内和体外EHT转录组揭示了SPI1的调节作用。在体外EHT过程中敲除SPI1导致造血祖细胞(HPCs)的生成及其分化潜力降低。通过多元分析,我们鉴定了KLF1和LYL1-红细胞/骨髓和淋巴样细胞特异性转录因子,分别作为SPI1的下游目标。过表达KLF1或LYL1部分挽救了SPI1敲低诱导的HPC形成减少。具体来说,KLF1过表达可恢复髓系潜能,而LYL1过表达重新建立淋巴谱系潜能。我们还在体内EHT的调节网络中观察到SPI1-LYL1轴。一起来看,我们的发现为SPI1在EHT期间调节谱系承诺的作用提供了新的思路,可能导致造血干细胞(HSC)的异质性。
    PU.1 (SPI1) is pivotal in hematopoiesis, yet its role in human endothelial-to-hematopoietic transition (EHT) remains unclear. Comparing human in vivo and in vitro EHT transcriptomes revealed SPI1\'s regulatory role. Knocking down SPI1 during in vitro EHT led to a decrease in the generation of hematopoietic progenitor cells (HPCs) and their differentiation potential. Through multi-omic analysis, we identified KLF1 and LYL1 - transcription factors specific to erythroid/myeloid and lymphoid cells, respectively - as downstream targets of SPI1. Overexpressing KLF1 or LYL1 partially rescues the SPI1 knockdown-induced reduction in HPC formation. Specifically, KLF1 overexpression restores myeloid lineage potential, while LYL1 overexpression re-establishes lymphoid lineage potential. We also observed a SPI1-LYL1 axis in the regulatory network in in vivo EHT. Taken together, our findings shed new light on the role of SPI1 in regulating lineage commitment during EHT, potentially contributing to the heterogeneity of hematopoietic stem cells (HSCs).
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    细胞通过液-液相分离(LLPS)对蛋白质进行区室化以在空间和时间上控制生化反应。其中,蛋白质向DNA病灶的募集和核仁运输是通过生物分子缩合发生的。在这个框架内,癌蛋白SET/TAF-Iβ在染色质重塑和DNA损伤反应中起关键作用,确实参与核仁核糖体合成的核磷蛋白(NPM1)也是如此。而NPM1的相分离是广泛的特征,对SET/TAF-Iβ所经历的事情知之甚少。这里,我们显示SET/TAF-Iβ与呼吸道细胞色素c(Cc)一起经历相分离,它在DNA损伤后易位到细胞核。在这里,我们报告了控制Cc诱导的SET/TAF-Iβ和NPM1相分离的分子机制,其中两个富含赖氨酸的Cc簇对于以特定和协调的方式识别两个伙伴的分子表面至关重要。Cc因此成为一个小的,具有序列编码的异型相分离特性的球形蛋白。
    Compartmentalization of proteins by liquid-liquid phase separation (LLPS) is used by cells to control biochemical reactions spatially and temporally. Among them, the recruitment of proteins to DNA foci and nucleolar trafficking occur by biomolecular condensation. Within this frame, the oncoprotein SET/TAF-Iβ plays a key role in both chromatin remodeling and DNA damage response, as does nucleophosmin (NPM1) which indeed participates in nucleolar ribosome synthesis. Whereas phase separation by NPM1 is widely characterized, little is known about that undergone by SET/TAF-Iβ. Here, we show that SET/TAF-Iβ experiences phase separation together with respiratory cytochrome c (Cc), which translocates to the nucleus upon DNA damage. Here we report the molecular mechanisms governing Cc-induced phase separation of SET/TAF-Iβ and NPM1, where two lysine-rich clusters of Cc are essential to recognize molecular surfaces on both partners in a specific and coordinated manner. Cc thus emerges as a small, globular protein with sequence-encoded heterotypic phase-separation properties.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    尽管最近在氧化DNA激活NLRP3的机制方面取得了进展,但氧化DNA与NLRP3缔合的分子机制和结果仍然未知。胞质NLRP3结合从线粒体释放的氧化DNA,随后触发炎症体激活。人糖基化酶(hOGG1)修复氧化的DNA损伤,抑制炎症体激活。NLRP3pyrin结构域的折叠包含氨基酸和类似于hOGG1的蛋白质折叠。使hOGG1能够结合和切割氧化的DNA的氨基酸在NLRP3中是保守的。我们发现NLRP3可以结合并切割线粒体DNA内的氧化鸟嘌呤。氧化的DNA与NLRP3的结合被也抑制hOGG1的小分子药物阻止。这些相同的药物也抑制炎性体活化。阐明这种机制将使药物模因的设计能够治疗炎性体病变,本文通过抑制巨噬细胞中白细胞介素-1β(IL-1β)产生的NLRP3Pyrin结构域抑制剂来说明。
    Despite recent advances in the mechanism of oxidized DNA activating NLRP3, the molecular mechanism and consequence of oxidized DNA associating with NLRP3 remains unknown. Cytosolic NLRP3 binds oxidized DNA which has been released from the mitochondria, which subsequently triggers inflammasome activation. Human glycosylase (hOGG1) repairs oxidized DNA damage which inhibits inflammasome activation. The fold of NLRP3 pyrin domain contains amino acids and a protein fold similar to hOGG1. Amino acids that enable hOGG1 to bind and cleave oxidized DNA are conserved in NLRP3. We found NLRP3 could bind and cleave oxidized guanine within mitochondrial DNA. The binding of oxidized DNA to NLRP3 was prevented by small molecule drugs which also inhibit hOGG1. These same drugs also inhibited inflammasome activation. Elucidating this mechanism will enable the design of drug memetics that treat inflammasome pathologies, illustrated herein by NLRP3 pyrin domain inhibitors which suppressed interleukin-1β (IL-1β) production in macrophages.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    Tel1/共济失调毛细血管扩张突变(ATM)激酶在响应DNA损伤时发挥多种功能,促进检查点介导的细胞周期阻滞和破碎DNA的修复。此外,酿酒酵母Tel1稳定了用拓扑异构酶毒喜树碱(CPT)处理后停止的复制叉。我们发现Exo1核酸酶的失活加剧了Tel1缺陷细胞对CPT和其他阻碍DNA复制的试剂的敏感性。此外,缺乏Exo1和Tel1活性的细胞在CPT存在下表现出持续的检查点激活,指示Tel1和Exo1限制与Mec1相关的检查点的激活。Tel1或其激酶活性的缺失增强了由Exo1依赖性方式的复制叉阻断诱导的反向DNA重复序列之间的重组。因此,我们建议Exo1处理tel1突变体中停滞叉处产生的中间体,以促进DNA复制恢复和细胞存活。
    Tel1/ataxia telangiectasia mutated (ATM) kinase plays multiple functions in response to DNA damage, promoting checkpoint-mediated cell-cycle arrest and repair of broken DNA. In addition, Saccharomyces cerevisiae Tel1 stabilizes replication forks that arrest upon the treatment with the topoisomerase poison camptothecin (CPT). We discover that inactivation of the Exo1 nuclease exacerbates the sensitivity of Tel1-deficient cells to CPT and other agents that hamper DNA replication. Furthermore, cells lacking both Exo1 and Tel1 activities exhibit sustained checkpoint activation in the presence of CPT, indicating that Tel1 and Exo1 limit the activation of a Mec1-dependent checkpoint. The absence of Tel1 or its kinase activity enhances recombination between inverted DNA repeats induced by replication fork blockage in an Exo1-dependent manner. Thus, we propose that Exo1 processes intermediates arising at stalled forks in tel1 mutants to promote DNA replication recovery and cell survival.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    棕榈疫霉,一种半营养性卵菌,导致几种经济上重要的热带作物的疾病,比如油棕,它导致了一种叫做芽腐烂(BR)的毁灭性疾病。尽管最近在理解宿主抗性和毒力机制方面取得了进展,从油棕分离出的棕榈假单胞菌的许多方面仍然未知。模型病理系统对于理解病原体和宿主之间的分子相互作用是有用的。在这项研究中,我们利用拟南芥Col-0的离体叶片和整株幼苗来描述和评估引起油棕BR的三种棕榈假单胞菌分离株(CPPhZC-05,CPPhZC-04,CPPhZOC-01)的感染过程。两个相容的分离株(CPPhZC-05和CPPhZOC-01)在接种后72小时(hpi)诱导了房水损伤,通过微观可视化显示,游动孢子在3hpi时被包裹和附着体渗透,其次是72hpi的孢子囊代。相比之下,不相容的分离株(CPPhZC-04)表现出不能穿透组织的囊肿,导致低叶定殖。通过RT-qPCR定量10个掌形虫感染相关基因的基因表达,揭示相容分离株中的过表达,但不是在不兼容的隔离中。此外,与水杨酸(SA)相关的关键基因,茉莉酸(JA),拟南芥中的乙烯(ET)在与三个分离株的相互作用中表现出调节作用。这些发现表明,棕榈假单胞菌可以感染拟南芥Col-0,并且在拟南芥-Col-0和棕榈假单胞菌之间的相互作用中观察到变异性。建立该病理系统有望增强我们对棕榈假单胞菌的病理和生理学的理解。
    Phytophthora palmivora, a hemibiotrophic oomycete, causes diseases in several economically important tropical crops, such as oil palm, which it is responsible for a devastating disease called bud rot (BR). Despite recent progress in understanding host resistance and virulence mechanisms, many aspects remain unknown in P. palmivora isolates from oil palm. Model pathosystems are useful for understanding the molecular interactions between pathogens and hosts. In this study, we utilized detached leaves and whole seedlings of Arabidopsis thaliana Col-0 to describe and evaluate the infection process of three P. palmivora isolates (CPPhZC-05, CPPhZC-04, CPPhZOC-01) that cause BR in oil palm. Two compatible isolates (CPPhZC-05 and CPPhZOC-01) induced aqueous lesions at 72 h post-inoculation (hpi), with microscopic visualization revealing zoospore encysting and appressorium penetration at 3 hpi, followed by sporangia generation at 72 hpi. In contrast, an incompatible isolate (CPPhZC-04) exhibited cysts that could not penetrate tissue, resulting in low leaf colonization. Gene expression of ten P. palmivora infection-related genes was quantified by RT-qPCR, revealing overexpression in compatible isolates, but not in the incompatible isolate. Additionally, key genes associated with salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) in Arabidopsis exhibited regulation during interaction with the three isolates. These findings demonstrate that P. palmivora can infect Arabidopsis Col-0, and variability is observed in the interaction between Arabidopsis-Col-0 and P. palmivora isolates. Establishing this pathosystem is expected to enhance our understanding of P. palmivora\'s pathology and physiology.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

公众号