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Distance measurement between two flexible sites in proteins in high viscosity medium at physiological temperature using continuous wave EPR

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Protein & Cell 2014年第5期5卷 334-337页

作者： Lu Yu Wei Wang shenglong ling Yao He Liang Xiao Kaiqi Wu Longhua Zhang Changlin Tian Hefei National Laboratory for Physical Science at the Microscale School of Life Science University of Science and Technology of ChinaHefei 230026China High Magnetic Field Laboratory Chinese Academy of SciencesHefei 230031China

Dear Editor, Accurate measurement of distances within and between biological macromolecules is important for structure-function studies, for investigating conformational changes and dynamics, and for improving restraints for molecular dynamics and modeling programs （Hellmich and Glaubitz, 2009）. Several methods have been developed to measure the distances between atoms, residues, and domains in single proteins and larger complexes. Fluorescence reso- nance energy transfer （FRET） is currently the most fre- quently used method to derive distances in cells or protein complexes, but the bulky size of the fluorescence probes and the strict requirement for frequency profile overlap between the acceptor and donor chromophores are limita- tions in many cases （Prevo and Peterman, 2014）.

关键词： Distance high viscosity EPR

Different conformational responses of the β2-adrenergic receptor-Gs complex upon binding of the partial agonist salbutamol or the full agonist isoprenaline

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National Science Review 2021年第9期8卷 111-120页

作者： Fan Yang shenglong ling Yingxin Zhou Yanan Zhang Pei Lv Sanling Liu Wei Fang Wenjing Sun Liaoyuan A.Hu Longhua Zhang Pan Shi Changlin Tian Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences University of Science and Technology of China Amgen Asia R&D Center Amgen Research Shanghai 201210 China3High Magnetic Field Laboratory Chinese Academy of Sciences

G protein-coupled receptors（GPCRs） are responsible for most cytoplasmic signaling in response to extracellular ligands with different efficacy profiles. Various spectroscopic techniques have identified that agonists exhibiting varying efficacies can selectively stabilize a specific conformation of the ***, the structural basis for activation of the GPCR-G protein complex by ligands with different efficacies is incompletely understood. To better understand the structural basis underlying the mechanisms by which ligands with varying efficacies differentially regulate the conformations of receptors and G proteins, we determined the structures of β2AR-Gαsβγ bound with partial agonist salbutamol or bound with full agonist isoprenaline using single-particle cryo-electron microscopy at resolutions of 3.26 ?A and3.80 ?A, respectively. Structural comparisons between the β2AR-Gs-salbutamol and β2AR-Gs-isoprenaline complexes demonstrated that the decreased binding affinity and efficacy of salbutamol compared with those of isoprenaline might be attributed to weakened hydrogen bonding interactions, attenuated hydrophobic interactions in the orthosteric binding pocket and different conformational changes in the rotamer toggle switch in TM6. Moreover, the observed stronger interactions between the intracellular loop 2 or 3（ICL2 or ICL3） of β2AR and Gαswith binding of salbutamol versus isoprenaline might decrease phosphorylation in the salbutamol-activated β2AR-Gs complex. From the observed structural differences between these complexes of β2AR, a mechanism of β2AR activation by partial and full agonists is proposed to provide structural insights into β2AR desensitization.

关键词： cryo-EM structure G protein-coupled receptor (GPCR) partial and full agonists conformational change desensitization

Binding coordination of metal ions in membrane proteins revealed by magnetic resonance methods

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Binding coordination of metal ions in membrane proteins reve...

中国化学会第十四届全国生物无机化学学术会议

作者： Lu Yu Yao He shenglong ling 田长麟 School of Life Sciences University of Science and Technology of China

＜正＞Metallo-membrane proteins are playing vital roles in cellular process, but the research methods and progress of metallo-membrane proteins are much lagged behind other membrane proteins. Combination of quadrupolar Nuclear magnetic resonance and quantum computation starting from three dimensional structures of proteins can illustrate the detail binding coordination of the metal ions. While Electron spin resonance can effectively illustrate the metal binding coordination and dynamic properties of metallo-membrane proteins.

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慈竹总黄酮提取工艺优化及抗氧化活性分析

食品科技 2024年第10期49卷 247-256页

作者：朱嘉杰林捷刘军李丽凌生隆江志聪田要美四川轻化工大学生物工程学院四川宜宾644000 四川省宜宾市思坡醋业有限责任公司四川宜宾644000

以慈竹叶、慈竹枝、慈竹秆为原料,以超声提取法为基础,分别采用醇提和水提2种方法提取慈竹中的活性成分,并测定粗提液中总黄酮、多酚、多糖的含量及其抗氧化能力,同时对慈竹叶总黄酮的提取工艺进行优化。结果表明,当提取时间为65 min、... 详细信息

以慈竹叶、慈竹枝、慈竹秆为原料,以超声提取法为基础,分别采用醇提和水提2种方法提取慈竹中的活性成分,并测定粗提液中总黄酮、多酚、多糖的含量及其抗氧化能力,同时对慈竹叶总黄酮的提取工艺进行优化。结果表明,当提取时间为65 min、乙醇体积分数为77%、料液比为1:26 g/mL时,慈竹叶醇提液的总黄酮含量最高,为2.61%。同时慈竹不同部位中活性成分和抗氧化能力有显著差异(P慈竹枝>慈竹秆。

关键词：慈竹总黄酮响应面法抗氧化活性

Properties of ABS/Organic-Attapulgite Nanocomposites Parts Fabricated by Fused Deposition Modeling

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Journal of Renewable Materials 2020年第11期8卷 1505-1518页

作者： ling Wang shenglong Jiang Chenchen Huang Pengyuan Dai Fenghua Liu Xiaopeng Qi Gaojie Xu Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou341000China Key Laboratory of Additive Manufacturing Materials of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of ScienceNingbo315201China

The paper discusses the mechanical and thermal performance manifested in natural nanorods attapulgite(ATP)reinforced Acrylonitrile butadiene styrene(ABS)nanocomposites in the process of fused deposition modeling(FDM).Molten extrusion technique was taken to manufacture the filaments of ABS/organic-attapulgite(OAT)nanocomposites with different mass fraction and the printing operation was made by one commercial FDM three-dimensional(3D)*** indicate that the mechanical performance of these FDM 3D printed specimens are improved obviously via the introduction of OAT,and tensile strength of the ABS/OAT nanocomposites parts with only 2 wt%OAT addition is enhanced by 48.1%.At the same time,the addition OAT can reduce the linear expansion coefficient and creep flexibility,and improve the thermal stability and dimensional accuracy of these FDM 3D printed parts.

关键词： ABS organic-attapulgite fused deposition modeling nanocomposites

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多应力耦合条件下氧气浓缩器退化建模

北京航空航天大学学报 2023年第2期49卷 472-481页

作者：潘晋新景博焦晓璇王生龙黄崧琳方玲空军工程大学航空工程学院西安710038 航空工业合肥江航飞机装备股份有限公司合肥230000

耦合应力条件下的建模是故障预测与健康管理领域的难点问题。以氧气浓缩器地面试验退化建模为例,针对试验中2种应力线性相关且耦合作用于氧气浓缩器退化的问题,提出了一种机理模型与数据驱动联合的偏微分方程建模方法。基于退化机理分... 详细信息

耦合应力条件下的建模是故障预测与健康管理领域的难点问题。以氧气浓缩器地面试验退化建模为例,针对试验中2种应力线性相关且耦合作用于氧气浓缩器退化的问题,提出了一种机理模型与数据驱动联合的偏微分方程建模方法。基于退化机理分析建立偏微分方程的基本形式,利用数据驱动的方法确定方程具体参数。通过偏微分方程建模,对2种应力进行解耦分析,确定引气湿度的增加会加快氧气浓缩器的退化速率,发现随着氧气浓缩器工作性能的退化,氧气浓缩器氧分压对引气压力的敏感性减弱,确定氧分压随引气压力变化斜率为健康因子。通过卡尔曼滤波器模式识别,确定氧气浓缩器退化可分为平稳阶段与退化阶段,与实际服役环境下氧气浓缩器退化数据对比,验证了氧气浓缩器两阶段退化特性。

关键词：多应力耦合退化建模偏微分方程氧气浓缩器卡尔曼滤波

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一种双折射平衡型光纤温度传感器的研究

传感技术学报 1999年第2期12卷 99-103页

作者：吕玲董胜龙黄登山西北工业大学电子工程系西安市710072

本文提出了一种双折射平衡型光纤高温传感系统．这种系统是通过检测光偏振态的变化来测量温度特性的．用两块蓝宝石单晶片作为探头中的敏感元件，它们首尾相接，第一块晶体的慢轴与第二块晶体的快轴相连．两块晶体的双折射相互平衡，提... 详细信息

本文提出了一种双折射平衡型光纤高温传感系统．这种系统是通过检测光偏振态的变化来测量温度特性的．用两块蓝宝石单晶片作为探头中的敏感元件，它们首尾相接，第一块晶体的慢轴与第二块晶体的快轴相连．两块晶体的双折射相互平衡，提高了传感器的灵敏度和准确性，温度的测量范围可达２０００℃以上．精度可达０．３５％，这种系统可广泛用于航空发动机进口温度测量．本文从物理模型和数学分析上证实了这种传感器的可行性，并通过计算机仿真结果对系统进行了验证．

关键词：光纤温度传感器偏振特性双折射平衡型

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我国机床数控化的现状和未来对策

制造技术与机床 2013年第4期 42-45页

作者：景富军谭胜龙刘玲范华献西南自动化研究所数控部四川绵阳621000

介绍目前我国机床的数控化现状。通过分析制约发展的部分因素,提出我国未来数控机床进一步优化的部分策略。

关键词：现状制约优化策略

肝癌相关抗原SMP30重组基因的构建、表达及分子伴侣共表达系统的探索

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生物技术通报 2012年第4期28卷 170-175页

作者：黄朋范升龙凌敏贺菽嘉周素芳广西医科大学生物化学与分子生物学教研室南宁530021

旨在通过应用基因工程的方法构建、表达和纯化肝癌相关抗原SMP30,研究共表达分子伴侣提高基因工程蛋白表达的可溶性及效率。PCR扩增SMP30 cDNA序列,用基因工程技术构建重组表达质粒,转化***21(DE3)pLysS宿主菌。表达蛋白经Ni-NTA亲和柱... 详细信息

旨在通过应用基因工程的方法构建、表达和纯化肝癌相关抗原SMP30,研究共表达分子伴侣提高基因工程蛋白表达的可溶性及效率。PCR扩增SMP30 cDNA序列,用基因工程技术构建重组表达质粒,转化***21(DE3)pLysS宿主菌。表达蛋白经Ni-NTA亲和柱纯化获得HIS-SMP30融合蛋白;分别将4种表达不同分子伴侣的质粒(pG-KJE8、pGro7、pKJE7、pTf16)转入***21(DE3)中;然后再将重组质粒转入含有分子伴侣质粒的细胞中,进行分子伴侣与重组质粒的共表达,SDS-PAGE检测目的蛋白的表达量与可溶性分析。经优化表达条件后,目的蛋白以包涵体形式表达,目的蛋白占总蛋白的60%以上;纯化后纯度高达95%以上;诱导共表达后,目的蛋白在上清含量极少,不到总表达目的蛋白的10%。成功构建出高效表达的SMP30重组质粒;加入到诱导表达体系中的4种分子伴侣质粒不能有效的促进可溶性蛋白的表达,pTf16共表达系统能增加目的蛋白表达量。

关键词： SMP30 基因工程表达与纯化分子伴侣质粒共表达