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1.
近年来煤基高附加值化学品提取制备的前沿科学研究发现,黄腐酸平台化合物(FAPC)作为一类具有特殊功效的团簇族特性组装分子集合体,在现代农业、生物医药及功能材料等方面有良好应用前景,黄腐酸平台化合物制备提取基础理论及化学构成研究具有重要科学意义;简介了黄腐酸平台化合物基于不同源物质的制备提取方法,重点阐述了煤基物选择解离规律、黄腐酸平台化合物特征官能团构成及自组装结构特性的光谱解析,研究结果表明:酸碱反应、离子交换、生物转化及微波等途径,可以实现黄腐酸平台化合物选择性制备提取;通过红外、核磁共振、荧光光谱、电子与振动光谱及分子模拟等手段,能够从不同光谱谱图特征指认对制备所得黄腐酸平台化合物分子群组分进行分子结构、官能团、分子链、自组装空间构型、基团结构及构建方式有效检测表征;多谱图综合揭示黄腐酸平台化合物主要由羧羟基、酚羟基、醌基和羰基类分子构成;选择性解离生成的活性小分子因相关分子特性取向形成自组装集体,具备界面友好、微纳米尺寸、电学储能及良好生物相容性特点;通过对比分析对黄腐酸平台化合物制备规律进行了优缺点揭示,并对黄腐酸平台化合物未来理论研究与应用前景做了展望。  相似文献   

2.
棕色脂肪组织(brown adipose tissue,BAT)在机体的能量代谢中起着极其重要的作用,且被认为是治疗肥胖的潜在靶点之一,然而目前对于BAT功能的代谢基础并不清楚.该文使用了基于核磁共振(NMR)和气相色谱(GC)技术的代谢组学方法,描述和比较了BAT与白色脂肪组织(white adipose tissue,WAT)的水溶性代谢物和脂肪酸组成的差异.研究结果表明,两种脂肪组织在糖代谢、氨基酸代谢、脂肪酸代谢、核苷酸代谢、胆碱代谢等多种代谢通路上均具有显著性差异,且这些差异与两种组织不同的生物学作用密切相关.以上研究结果将为解析BAT功能分子机制提供了线索和基础数据.  相似文献   

3.
Here we present results obtained in our group from cell-based screenings of microbial secondary metabolites using intact microbial and mammalian cells having specific functions. We present summaries of the following five categories of compounds and the strategies that were used to identify them. (1) Antibacterial agents targeting cell wall peptidoglycan synthesis as well as active agents against organisms other than bacteria were identified by a combination of Bacillus subtilis and Mycoplasma as test organisms. (2) Antimetabolites, such as herbicidal agents targeting glutamine synthase, were identified using B. subtilis grown on minimal medium with or without the addition of glutamine and folate inhibitors by combination of B. subtilis and Enterococcus faecium, which have distinct folate metabolic pathways. (3) Among inhibitors of lipid metabolism, acyl-CoA synthetase inhibitors were identified using two mutants of C. lipolytica with different deletion sites in the fatty acid metabolic pathways, HMG-CoA synthase inhibitors were identified using Vero cells cultured in the presence and absence of mevalonate, and anti-atherosclerosis agents were identified using macrophages. (4) IL-6 inhibitors were detected by a combination of IL- 6-dependent and independent murine hybridoma MH60 cells, and (5) Small molecules with TNF-like activities were identified using a mouse neuroblastoma cell line. Some advantages of such screening method and the significance of the identified compounds are discussed.  相似文献   

4.
NMR detection of multiply labeled compounds in biological samples is often used to follow metabolic pathways. Detection of protons bound to 13C atoms offers a more sensitive approach than direct 13C detection, but generally results in the loss of carbon-carbon coupling information. We have modified an HSQC sequence to refocus the carbon chemical shifts in order to obtain a proton-correlated 13C homonuclear J spectrum, which allows us to measure singly and doubly labeled compounds in the same spectrum.  相似文献   

5.
喻祖国  肖前军  石龙  余君武  Vo Anh 《中国物理 B》2010,19(6):68701-068701
Investigating the biological function of proteins is a key aspect of protein studies.Bioinformatic methods become important for studying the biological function of proteins.In this paper,we first give the chaos game representation (CGR) of randomly-linked functional protein sequences,then propose the use of the recurrent iterated function systems (RIFS) in fractal theory to simulate the measure based on their chaos game representations.This method helps to extract some features of functional protein sequences,and furthermore the biological functions of these proteins.Then multifractal analysis of the measures based on the CGRs of randomly-linked functional protein sequences are performed.We find that the CGRs have clear fractal patterns.The numerical results show that the RIFS can simulate the measure based on the CGR very well.The relative standard error and the estimated probability matrix in the RIFS do not depend on the order to link the functional protein sequences.The estimated probability matrices in the RIFS with different biological functions are evidently different.Hence the estimated probability matrices in the RIFS can be used to characterise the difference among linked functional protein sequences with different biological functions.From the values of the D q curves,one sees that these functional protein sequences are not completely random.The D q of all linked functional proteins studied are multifractal-like and sufficiently smooth for the C q (analogous to specific heat) curves to be meaningful.Furthermore,the D q curves of the measure μ based on their CGRs for different orders to link the functional protein sequences are almost identical if q ≥ 0.Finally,the C q curves of all linked functional proteins resemble a classical phase transition at a critical point.  相似文献   

6.
The emergence and evolution of metabolic pathways represented a crucial step in molecular and cellular evolution. In fact, the exhaustion of the prebiotic supply of amino acids and other compounds that were likely present in the ancestral environment, imposed an important selective pressure, favoring those primordial heterotrophic cells which became capable of synthesizing those molecules. Thus, the emergence of metabolic pathways allowed primitive organisms to become increasingly less-dependent on exogenous sources of organic compounds.Comparative analyses of genes and genomes from organisms belonging to Archaea, Bacteria and Eukarya revealed that, during evolution, different forces and molecular mechanisms might have driven the shaping of genomes and the arisal of new metabolic abilities. Among these gene elongations, gene and operon duplications undoubtedly played a major role since they can lead to the (immediate) appearance of new genetic material that, in turn, might undergo evolutionary divergence giving rise to new genes coding for new metabolic abilities. Gene duplication has been invoked in the different schemes proposed to explain why and how the extant metabolic pathways have arisen and shaped. Both the analysis of completely sequenced genomes and directed evolution experiments strongly support one of them, i.e. the patchwork hypothesis, according to which metabolic pathways have been assembled through the recruitment of primitive enzymes that could react with a wide range of chemically related substrates. However, the analysis of the structure and organization of genes belonging to ancient metabolic pathways, such as histidine biosynthesis and nitrogen fixation, suggested that other different hypothesis, i.e. the retrograde hypothesis or the semi-enzymatic theory, may account for the arisal of some metabolic routes.  相似文献   

7.
NMR detection of multiply labeled compounds in biological samples is often used to follow metabolic pathways. Detection of protons bound to13C atoms offers a more sensitive approach than direct13C detection, but generally results in the loss of carbon–carbon coupling information. We have modified an HSQC sequence to refocus the carbon chemical shifts in order to obtain a proton-correlated13C homonuclearJspectrum, which allows us to measure singly and doubly labeled compounds in the same spectrum.  相似文献   

8.
Jun-Bao Ma 《中国物理 B》2021,30(10):108701-108701
The realization of protein functional movement is usually accompanied by specific conformational changes, and there exist some key residues that mediate and control the functional motions of proteins in the allosteric process. In the present work, the perturbation-response scanning method developed by our group was combined with the molecular dynamics (MD) simulation to identify the key residues controlling the functional movement of proteins. In our method, a physical quantity that is directly related to protein specific function was introduced, and then based on the MD simulation trajectories, the perturbation-response scanning method was used to identify the key residues for functional motions, in which the residues that highly correlated with the fluctuation of the function-related quantity were identified as the key residues controlling the specific functional motions of the protein. Two protein systems, i.e., the heat shock protein 70 and glutamine binding protein, were selected as case studies to validate the effectiveness of our method. Our calculated results are in good agreement with the experimental results. The location of the key residues in the two proteins are similar, indicating the similar mechanisms behind the performance of their biological functions.  相似文献   

9.
《Current Applied Physics》2014,14(6):876-880
Calcium phosphate compounds have been widely studied for biomedical applications because of their chemical and structural similarity to the mineral phase constituting bone and teeth. In this work, biphasic calcium phosphate ceramics (HAP/β-TCP), with tunable phase composition ratio, were synthesized by a solid state reaction process. The effect of varying the heat treatment temperature (700, 800, 900, 1000, and 1100 °C) on the formation of the ceramic materials and their related cytotoxicity were examined. The phase composition and morphology of the prepared ceramic powders were characterized by X-ray diffraction and scanning electron microscopy, and the functional groups were analyzed using Fourier transform infrared spectroscopy and Raman spectroscopy. Cell culture experiments, using murine macrophages, showed that the synthesized HAP/β-TCP materials did not exhibit cytotoxicity regardless of the doses assayed or the differences in composition ratio of HAP/β-TCP, suggesting the potential of HAP/β-TCP for biological applications.  相似文献   

10.
肿瘤是一种代谢疾病,癌基因表达对肿瘤细胞代谢的影响是目前肿瘤研究的热点之一.本文利用基于核磁共振氢谱(1H NMR)的代谢组学方法对癌基因SIRT7低表达胶质瘤细胞株的代谢特征进行分析,寻找与SIRT7基因表达相关的特征性代谢物和代谢通路.分析结果表明,SIRT7基因低表达组与对照组细胞的代谢轮廓存在显著性差异,其细胞水溶性萃取物中有22种代谢物浓度发生明显变化.与对照组相比,SIRT7基因低表达胶质瘤细胞株中乳酸、甘氨酸、谷氨酸等12种代谢物浓度升高;缬氨酸、亮氨酸、赖氨酸等10种代谢物浓度降低.通路富集分析提示氨酰-tRNA生物合成、氨基酸代谢等代谢通路与SIRT7低表达密切相关.以上结果为进一步阐明癌基因SIRT7调控胶质瘤细胞代谢的作用机制提供了理论依据.  相似文献   

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