Asp, aspartic acid

Asp,天冬氨酸
  • 文章类型: Journal Article
    未经证实:缺乏对新型冠状病毒疾病的治疗导致寻找能够抑制病毒复制的特定抗病毒药物。植物界已被证明是具有抗病毒潜力的新分子的重要来源。
    UNASSIGNED:本研究旨在利用各种计算工具来鉴定最有资格的候选药物,这些候选药物具有通过抑制主要蛋白酶(Mpro)酶来阻止SARS-COV-2病毒复制的能力。
    未经证实:我们选择了提取物对先前发现的冠状病毒具有抑制潜力的植物。调查了它们的植物成分,并制备了100个分子的文库。然后,计算工具,如分子对接,利用ADMET和分子动力学模拟来筛选化合物并评估它们对Mpro酶的影响。
    未经鉴定:所有的植物成分都显示出对Mpro酶的良好结合亲和力。其中月桂碱具有最高的结合亲和力,即-294.1533kcal/mol。在ADMET分析中,模拟了1.2ns的最佳三种配体,然后将其中的稳定配体进一步模拟20ns。结果表明,在月桂碱w.r.t.蛋白质残基中未观察到构象变化,较低的RMSD值表明月桂碱-蛋白质复合物稳定20ns。
    未经批准:劳罗利辛,黑斑草根的活性成分,被发现具有良好的ADMET谱并且具有停止酶活性的能力。因此,这使得月桂碱成为治疗COVID-19的良好候选药物。
    UNASSIGNED: Lack of treatment of novel Coronavirus disease led to the search of specific antivirals that are capable to inhibit the replication of the virus. The plant kingdom has demonstrated to be an important source of new molecules with antiviral potential.
    UNASSIGNED: The present study aims to utilize various computational tools to identify the most eligible drug candidate that have capabilities to halt the replication of SARS-COV-2 virus by inhibiting Main protease (Mpro) enzyme.
    UNASSIGNED: We have selected plants whose extracts have inhibitory potential against previously discovered coronaviruses. Their phytoconstituents were surveyed and a library of 100 molecules was prepared. Then, computational tools such as molecular docking, ADMET and molecular dynamic simulations were utilized to screen the compounds and evaluate them against Mpro enzyme.
    UNASSIGNED: All the phytoconstituents showed good binding affinities towards Mpro enzyme. Among them laurolitsine possesses the highest binding affinity i.e. -294.1533 kcal/mol. On ADMET analysis of best three ligands were simulated for 1.2 ns, then the stable ligand among them was further simulated for 20 ns. Results revealed that no conformational changes were observed in the laurolitsine w.r.t. protein residues and low RMSD value suggested that the Laurolitsine-protein complex was stable for 20 ns.
    UNASSIGNED: Laurolitsine, an active constituent of roots of Lindera aggregata, was found to be having good ADMET profile and have capabilities to halt the activity of the enzyme. Therefore, this makes laurolitsine a good drug candidate for the treatment of COVID-19.
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  • 文章类型: Journal Article
    鱼藤酮是一种广谱农药,用于世界各地的各种农业实践。人类通过口服接触这种化学物质,鼻部,和真皮路线。鱼藤酮的吸入使肺的生物分子成分暴露于这种化学物质。肺的生物物理活动由肺表面活性剂精确调节以促进气体交换。表面活性蛋白(SP)是肺表面活性物质的基本成分。SP-A和SP-D等SP具有抗菌活性,可为肺部感染提供重要的第一道防线,而SP-B和SP-C主要参与呼吸循环和降低空气-水界面的表面张力。在这项研究中,使用AutoDockVina进行了分子对接分析,以研究鱼藤酮与四种SP的结合潜力。结果表明,鱼藤酮可以与SP-A的碳水化合物识别域(CRD)结合,N-,和SP-B的C末端肽,SP-C,和SP-D的CRD在多个位点通过几个相互作用介质如H键,C-H键,烷基键,pi-pi堆叠,范德华互动,和其他。鱼藤酮与SP的这种相互作用可以破坏肺中SP的生物物理和抗微生物功能,这可能会引起呼吸道疾病和病原体感染。
    Rotenone is a broad-spectrum pesticide employed in various agricultural practices all over the world. Human beings are exposed to this chemical through oral, nasal, and dermal routes. Inhalation of rotenone exposes bio-molecular components of lungs to this chemical. Biophysical activity of lungs is precisely regulated by pulmonary surfactant to facilitate gaseous exchange. Surfactant proteins (SPs) are the fundamental components of pulmonary surfactant. SPs like SP-A and SP-D have antimicrobial activities providing a crucial first line of defense against infections in lungs whereas SP-B and SP-C are mainly involved in respiratory cycle and reduction of surface tension at air-water interface. In this study, molecular docking analysis using AutoDock Vina has been conducted to investigate binding potential of rotenone with the four SPs. Results indicate that, rotenone can bind with carbohydrate recognition domain (CRD) of SP-A, N-, and C- terminal peptide of SP-B, SP-C, and CRD of SP-D at multiples sites via several interaction mediators such as H bonds, C-H bonds, alkyl bonds, pi-pi stacked, Van der Waals interaction, and other. Such interactions of rotenone with SPs can disrupt biophysical and anti-microbial functions of SPs in lungs that may invite respiratory ailments and pathogenic infections.
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  • 文章类型: Journal Article
    质膜转运蛋白在营养物质的导入中起着关键作用,包括糖,氨基酸,核碱基,羧酸,和金属离子,围绕真菌细胞。通过胞吞作用选择性去除这些转运蛋白是最重要的调节机制之一,可确保细胞快速适应不断变化的环境(例如,营养波动或不同的压力)。这种机制的核心是蛋白质网络,其中包括与抑制蛋白相关的运输衔接子(ART),该衔接子将泛素连接酶Rsp5与营养转运蛋白和内吞因子联系起来。转运蛋白构象变化,以及其胞质末端/环与质膜脂质之间的动态相互作用,在胞吞过程中也很关键。这里,我们回顾了有关营养转运蛋白内吞作用的分子机制的最新知识和最新发现,在酿酒酵母酵母和某些丝状真菌曲霉中。我们详细阐述了在自然界中发现的动态条件下,紧密调节的内吞作用对细胞适应性的生理重要性,并强调了对该过程的进一步理解和工程对于最大化滴度至关重要。工业生物技术过程中工程细胞工厂的速率和产量(TRY)值。
    Plasma membrane transporters play pivotal roles in the import of nutrients, including sugars, amino acids, nucleobases, carboxylic acids, and metal ions, that surround fungal cells. The selective removal of these transporters by endocytosis is one of the most important regulatory mechanisms that ensures a rapid adaptation of cells to the changing environment (e.g., nutrient fluctuations or different stresses). At the heart of this mechanism lies a network of proteins that includes the arrestin-related trafficking adaptors (ARTs) which link the ubiquitin ligase Rsp5 to nutrient transporters and endocytic factors. Transporter conformational changes, as well as dynamic interactions between its cytosolic termini/loops and with lipids of the plasma membrane, are also critical during the endocytic process. Here, we review the current knowledge and recent findings on the molecular mechanisms involved in nutrient transporter endocytosis, both in the budding yeast Saccharomyces cerevisiae and in some species of the filamentous fungus Aspergillus. We elaborate on the physiological importance of tightly regulated endocytosis for cellular fitness under dynamic conditions found in nature and highlight how further understanding and engineering of this process is essential to maximize titer, rate and yield (TRY)-values of engineered cell factories in industrial biotechnological processes.
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  • 文章类型: Journal Article
    在过去的30年里,自从发现钒是在被膜动物的某些酶中以及可能在哺乳动物中发现的辅因子以来,已经开发了不同的钒基药物靶向治疗不同的病症。到目前为止,胰岛素模拟物的体外研究,某些钒化合物的抗肿瘤和抗寄生虫活性导致了其无机和生物无机化学的巨大繁荣。在受控条件下,钒与氨基酸的化学形态研究或,即使在血浆中,对于理解例如在生理水平上的钒抗糖尿病复合物的生物转化至关重要,提供其作用机制的线索。本文进行了文献研究,重点介绍了钒与不同氨基酸的化学形态,并回顾了其他一些重要方面,例如几种钒配合物的化学和治疗应用。
    In the last 30 years, since the discovery that vanadium is a cofactor found in certain enzymes of tunicates and possibly in mammals, different vanadium-based drugs have been developed targeting to treat different pathologies. So far, the in vitro studies of the insulin mimetic, antitumor and antiparasitic activity of certain compounds of vanadium have resulted in a great boom of its inorganic and bioinorganic chemistry. Chemical speciation studies of vanadium with amino acids under controlled conditions or, even in blood plasma, are essential for the understanding of the biotransformation of e.g. vanadium antidiabetic complexes at the physiological level, providing clues of their mechanism of action. The present article carries out a bibliographical research emphaticizing the chemical speciation of the vanadium with different amino acids and reviewing also some other important aspects such as its chemistry and therapeutical applications of several vanadium complexes.
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  • 文章类型: Journal Article
    同型半胱氨酸(Hcy)升高与几种病理有关。与Hcy相关的基因-饮食相互作用可用于定制饮食建议以降低疾病发生率。为了探索这种可能性,我们调查了人体测量学之间的相互作用,生化标志物和饮食和单核苷酸多态性(SNP)与Hcy浓度的关系。在2010年南非黑人中分析了Hcy代谢酶的五个SNP。
    每个额外的亚甲基四氢叶酸还原酶(MTHFR)C677T次要等位基因拷贝的Hcy较高,但蛋氨酸合成酶(MTR)2756AA纯合子低于杂合子。含有胱硫醚β合酶(CBS)833T/844ins68的个体Hcy浓度低于其他人。没有观察到任何人体测量标记的交互效应。MTHFRC677T和CBST833C/844ins68纯合子次要等位基因携带者随着高密度脂蛋白胆固醇(HDL-c)的升高而呈现较低的Hcy。在TT和TC基因型中,Hcy浓度与膳食蛋白和动物蛋白摄入量呈负相关,但在CBST833C/844ins68的CC基因型中呈阳性。随着添加糖摄入量的增加,MTHFRC677T的TT纯合子中的Hcy明显更高。在CBST833C/844ins68主要等位基因携带者中,生物素摄入与Hcy呈负相关;但在具有纯合次要等位基因的人群中呈正相关。
    Hcy-SNP关联受饮食调节,并开辟了调用饮食干预治疗高同型半胱氨酸血症的可能性。未来的干预试验应进一步探索观察到的基因-饮食和基因-血脂相互作用。
    UNASSIGNED: Elevated homocysteine (Hcy) is associated with several pathologies. Gene-diet interactions related to Hcy might be used to customize dietary advice to reduce disease incidence. To explore this possibility, we investigated interactions between anthropometry, biochemical markers and diet and single-nucleotide polymorphisms (SNPs) in relation to Hcy concentrations. Five SNPs of Hcy-metabolizing enzymes were analyzed in 2010 black South Africans.
    UNASSIGNED: Hcy was higher with each additional methylenetetrahydrofolate reductase (MTHFR) C677T minor allele copy, but was lower in methionine synthase (MTR) 2756AA homozygotes than heterozygotes. Individuals harboring cystathionine β synthase (CBS) 833 T/844ins68 had lower Hcy concentrations than others. No interactive effects were observed with any of the anthropometrical markers. MTHFR C677T and CBS T833C/844ins68 homozygote minor allele carriers presented with lower Hcy as high density lipoprotein cholesterol (HDL-c) increased. Hcy concentrations were negatively associated with dietary protein and animal protein intake in the TT and TC genotypes, but positively in the CC genotype of CBS T833C/844ins68. Hcy was markedly higher in TT homozygotes of MTHFR C677T as added sugar intake increased. In CBS T833C/844ins68 major allele carriers, biotin intake was negatively associated with Hcy; but positively in those harboring the homozygous minor allele.
    UNASSIGNED: The Hcy-SNP associations are modulated by diet and open up the possibility of invoking dietary interventions to treat hyperhomocysteinemia. Future intervention trials should further explore the observed gene-diet and gene-blood lipid interactions.
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  • 文章类型: Journal Article
    我们表明,具有无功能突变G150D的αLβ2整合素不能用Mg/EGTA诱导表达mAbKIM127表位,报告了腿部延伸的构象。我们将研究扩展到αIIbβ3,一种没有αI结构域的整联蛋白。等效突变,即G161D,也导致了一个可以表达的,但非粘附性αIIbβ3整合素。跨越β3I结构域的α1-α1螺旋的合成肽的NMR研究显示野生型和突变型肽都是α-螺旋的。然而,而在野生型肽中,这种螺旋是连续的,突变体呈现不连续性,或者扭结,正好在G161D突变位点.我们的结果表明,突变可能将整联蛋白异源二聚体锁定在弯曲的构象中,从而阻止了整联蛋白通过构象延伸的激活。
    We showed that the αLβ2 integrin with the non-functional mutation G150D cannot be induced with Mg/EGTA to express the mAb KIM127 epitope, which reports the leg-extended conformation. We extended the study to the αIIbβ3, an integrin without an αI domain. The equivalent mutation, i.e. G161D, also resulted in an expressible, but non-adhesive αIIbβ3 integrin. An NMR study of synthetic peptides spanning the α1-α1\' helix of the β3 I domain shows that both wild-type and mutant peptides are α-helical. However, whereas in the wild-type peptide this helix is continuous, the mutant presents a discontinuity, or kink, precisely at the site of mutation G161D. Our results suggest that the mutation may lock integrin heterodimers in a bent conformation that prevents integrin activation via conformational extension.
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  • 文章类型: Journal Article
    目的:非酒精性脂肪性肝病(NAFLD)是最常见的慢性肝病,与肝脏和心血管疾病的风险增加以及死亡率相关。NAFLD可以从单纯性肝脂肪变性发展为非酒精性脂肪性肝炎(NASH)。然而,诱发这一进展的机制仍未定义。值得注意的是,肝线粒体功能障碍是NASH患者的常见表现.由于缺乏合适的实验动物模型,尚未评估这种线粒体功能障碍是否在NASH的发展中起致病作用.
    方法:为了确定明确定义的线粒体功能障碍在基线和饮食挑战期间对肝脏生理的影响,采用C57BL/6J-mt(FVB/N)小鼠。先前已报道这种再生近交系表现出线粒体呼吸降低,可能与线粒体ATP合酶蛋白8(mt-ATP8)的非同义基因变异(nt7778G/T)有关。
    结果:在基线条件下,C57BL/6J-mt(FVB/N)小鼠表现出肝线粒体功能障碍,其特征是ATP产生减少和活性氧(ROS)形成增加。此外,影响脂质代谢的基因差异表达,这些动物的肝脏甘油三酯和胆固醇水平发生了变化,各种酰基肉碱被改变了,指向受损的线粒体肉碱穿梭。然而,在十二个月的时间里,未观察到自发性肝脂肪变性或炎症。另一方面,在蛋氨酸和胆碱缺乏饮食或西式饮食的饮食挑战,C57BL/6J-mt(FVB/N)小鼠发展为以脂质积累为特征的加重脂肪性肝炎,肝细胞膨胀和免疫细胞浸润。
    结论:我们在线粒体多态性与肝脏线粒体功能障碍相关的小鼠中观察到明显的代谢改变。然而,第二次打击,比如饮食压力,需要引起肝脏脂肪变性和炎症。这项研究表明肝线粒体功能障碍在实验性NASH的发展中的致病作用。
    OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease and is associated with an enhanced risk for liver and cardiovascular diseases and mortality. NAFLD can progress from simple hepatic steatosis to non-alcoholic steatohepatitis (NASH). However, the mechanisms predisposing to this progression remain undefined. Notably, hepatic mitochondrial dysfunction is a common finding in patients with NASH. Due to a lack of appropriate experimental animal models, it has not been evaluated whether this mitochondrial dysfunction plays a causative role for the development of NASH.
    METHODS: To determine the effect of a well-defined mitochondrial dysfunction on liver physiology at baseline and during dietary challenge, C57BL/6J-mt(FVB/N) mice were employed. This conplastic inbred strain has been previously reported to exhibit decreased mitochondrial respiration likely linked to a non-synonymous gene variation (nt7778 G/T) of the mitochondrial ATP synthase protein 8 (mt-ATP8).
    RESULTS: At baseline conditions, C57BL/6J-mt(FVB/N) mice displayed hepatic mitochondrial dysfunction characterized by decreased ATP production and increased formation of reactive oxygen species (ROS). Moreover, genes affecting lipid metabolism were differentially expressed, hepatic triglyceride and cholesterol levels were changed in these animals, and various acyl-carnitines were altered, pointing towards an impaired mitochondrial carnitine shuttle. However, over a period of twelve months, no spontaneous hepatic steatosis or inflammation was observed. On the other hand, upon dietary challenge with either a methionine and choline deficient diet or a western-style diet, C57BL/6J-mt(FVB/N) mice developed aggravated steatohepatitis as characterized by lipid accumulation, ballooning of hepatocytes and infiltration of immune cells.
    CONCLUSIONS: We observed distinct metabolic alterations in mice with a mitochondrial polymorphism associated hepatic mitochondrial dysfunction. However, a second hit, such as dietary stress, was required to cause hepatic steatosis and inflammation. This study suggests a causative role of hepatic mitochondrial dysfunction in the development of experimental NASH.
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  • 文章类型: Journal Article
    作为真核核糖体不可或缺的组成部分,核糖体蛋白L23a在蛋白质合成中起着重要作用,折叠和分类。在这项研究中,从小尾寒羊耳缘组织cDNA表达文库中筛选出大小为471bp的核糖体蛋白L23a的cDNA片段,它具有157个氨基酸和17.69kDa的分子量。L23a的核苷酸序列与人类的核苷酸序列具有很高的同源性,鼠标,牛和猪占91.51%,88.32%,96.18%和93.84%,分别。L23a是高度基础的,含有一个合并的45精氨酸,Lys,和His残基,只有14个Asp和Glu残基。用质粒pEGFP-N3-RPL23A转染后,分析了重组L23a蛋白在Ujumqin绵羊成纤维细胞中的表达模式和细胞内分布,转染后24h细胞的细胞质和核仁均有绿色荧光信号,阳性细胞数随时间增加,转染48小时后达到峰值水平。转染效率为22.8%。重组L23a基因在大肠杆菌中的表达模式随诱导温度的不同而不同,电感浓度和诱导时间,当IPTG浓度为0.1mmol/L,诱导温度为37°时,L23a蛋白表达随诱导时间增加。
    As an indispensable component of the eukaryotic ribosome, ribosomal protein L23a plays an important role in protein synthesis, folding and sorting. In this study, the cDNA fragment of ribosomal protein L23a with 471 bp in size was screened from the Small Tail Han sheep ear marginal tissue cDNA expression library, it has 157 amino acids and a molecular weight of 17.69 kDa. The nucleotide sequence of L23a shares a high homology with those of human, mouse, cattle and pig of 91.51%, 88.32%, 96.18% and 93.84%, respectively. L23a is highly basic, containing a combined 45 Arg, Lys, and His residues and only 14 Asp and Glu residues. The expression pattern and intra-cellular distribution of recombinant L23a proteins in Ujumqin sheep fibroblast cells were analyzed after transfected with the plasmid pEGFP-N3-RPL23A, there were green fluorescence signals both in the cytoplasm and nucleolus of transfected cells after 24 h, the number of positive cells was increased with time, and they reached the peak level after 48 h of transfection. The transfection efficiency was 22.8%. Expression patterns of recombinant L23a gene in Escherichia coli were different with induction temperature, inductor concentration and induction time, when the IPTG concentration was 0.1 mmol/L and induction temperature was 37°, L23a protein expression was increased with induction time.
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