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Designed histidine-rich peptide self-assembly for accelerating oxidase-catalyzed reactions

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Nano Research 2022年第5期15卷 4032-4038页

作者： Peidong Du Siyuan Liu Hao Sun Haifeng Wu zhen-gang wang State Key Laboratory of Organic-Inorganic Composites Key Lab of Biomedical Materials of Natural Macromolecules(Beijing University of Chemical TechnologyMinistry of Education)Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China

It is an important goal for supramolecular chemistry to develop synthetic enzyme mimics rivaling native enzymes,while de novo fabrication of such mimics remains a ***,the catalytic groups from the supramolecular complex can be integrated with the active sites of natural ***,we present a supramolecular catalytic hybrid that is self-assembled from oligohistidine-based peptides and a heme-dependent *** results indicate that the peptides altered the enzyme conformation,promoted the transitions between the resting and the intermediate states of the heme,and increased the turnover rate of the enzyme by up to *** propose that the histidine residues from the peptides may collaborate with the groups in the natural heme pocket to accelerate the catalytic cycles of the *** observations underline the advantages of the supramolecular approach and suggest that molecular self-assembly may combine with enzymes to provide a simple strategy to engineer the enzymatic active sites.

关键词： self-assembly oligohistidine enzymes biocatalysis active site

Designed imidazole-based supramolecular catalysts for accelerating oxidation/hydrolysis cascade reactions

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Nano Research 2024年第6期17卷 4916-4923页

作者： Yuanxi Liu Wenjie Xu Shichao Xu Haifeng Wu Baoli Zhang Li Song zhen-gang wang State Key Laboratory of Organic-Inorganic Composites Key Lab of Biomedical Materials of Natural Macromolecules(Ministry of Education)Beijing Laboratory of Biomedical MaterialsCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230029China

Reconstructing enzymatic active sites presents a significant challenge due to the intricacies involved in achieving enzyme-like scaffold folding and spatial arrangement of essential functional *** is also a growing interest in building biocatalytic networks,wherein multiple enzymatic active sites are localized within a single artificial system,allowing for cascaded *** this work,we report the self-assembly of imidazole or its derivatives with fluorenylmethyloxycarbonyl-modified histidine and Cu2+to fabricate a supramolecular catalyst,which possesses catechol oxidase-like dicopper center with multiple imidazole as the coordination *** electron microscopy,low-temperature X-band continuous-wave electron paramagnetic resonance,K-edge X-ray absorption spectra/the extended X-ray absorption fine structure analysis,and density functional theory modeling were used for the structural characterization of the *** phenol derivatives and the dissolved oxygen were used as the substrates,with the addition of 4-aminoantipyrine to generate a red adduct with a maximum absorbance at 510 nm,for obtaining time-dependent absorbance change curves and estimating the *** results reveal that the addition of imidazole synergistically accelerates the oxidative activity about 10-fold and the hydrolysis activity about 14-fold than fluorenylmethyloxycarbonyl modified-histidine/Cu2+.The supramolecular nanoassembly also exhibits the ability to catalyze oxidation/hydrolysis cascade reactions,converting 2′,7′-dichlorofluorescin diacetate into 2′,7′-*** process can be regulated through the methylation of the imidazole component at various *** work may contribute to the design of advanced biomimetic catalysts,and shed light on early structural models of the active sites of the primitive copper-dependent enzymes.

关键词： enzyme mimic self-assembly supramolecular catalyst cascade reactions

Self-Energy Effects of Salt Ions on Phase Behavior and Interfacial Properties

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Self-Energy Effects of Salt Ions on Phase Behavior and Inter...

中国化学会2014年大分子体系理论、模拟与计算研讨会

作者： zhen-gang wang Division of Chemistry and Chemical Engineering California Institute of Technology Pasadena CA 91125

Ions are essential in physical chemistry,colloidal science,electrochemistry,biology and many other areas of science and *** their role is commonly described in terms of screening and translational entropy,many phenomena,ranging from some classical experimental observations made many decades ago to some new systems of current interest,cannot be explained,even qualitatively,by these concepts.A key effect that is often ignored or inadequately

关键词： Self-Energy Effects of Salt Ions on Phase Behavior and Interfacial Properties

ELECTROSTATIC CORRELATIONS AND THE POLYELECTROLYTE SELF-ENERGY

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ELECTROSTATIC CORRELATIONS AND THE POLYELECTROLYTE SELF-ENER...

中国化学会2016年软物质理论计算与模拟会议

作者： zhen-gang wang Division of Chemistry and Chemical Engineering California Institute of Technology

＜正＞Electrostatic correlations are responsible for a variety of important phenomena in polyelectrolyte systems,from ion condensation to complex coacervation.A key theoretical challenge is the proper account of the dependence of the chain conformation on the concentration and/or salt *** widely used Voorn-Overbeek theory completely ignores the chain connectivity,while

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Barotropic phase behavior of compressible polymer blends

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Barotropic phase behavior of compressible polymer blends

中国化学会2016年软物质理论计算与模拟会议

作者： Xiaofei Xu Yu-Qiang Ma zhen-gang wang Center for Soft Condensed Matter Physics and Interdisciplinary Research Soochow University Collaborative Innovation Center of Advanced Microstructures and Department of Physics Nanjing University Division of Chemistry and Chemical Engineering California Institute of Technology

We study the phase behavior of polymer blends by using an equation-of-state *** is found that the blend of hard polymers with unequal segment sizes will demix with increasing pressure(P).This barotropic phase behavior is driven by the entropy and can be understood by examining the excess free energy at fixed *** demixing pressure decreases with increasing degrees of polymerization(N).For P < 200 MPa,the effective kai parameter χ of the blend has a linear dependence on the *** derive a simple analytical expression for the composition and χ at the critical *** show that the critical χ and critical P scale with N-2 in mean-field theory.

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Prognostic factors and staging systems of multiple myeloma:a single centre study in China

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Chinese Medical Journal 2007年第19期120卷 1655-1658页

作者： TAO Zhong-fei FU Wei-jun YUAN zhen-gang wang Dong-xing CHEN Yu-bao HOU Jian Department of Haematology Shanghai Changzheng Hospital Second Military Medical University Shanghai 200003 China

Background Previous studies found a range of prognostic factors but no consensus about the proper staging system for multiple myeloma has been achieved. This study explored the prognostic factors to find a staging system for multiple myeloma most suitable for Chinese patients. Methods Between February 1990 to August 2004, 206 patients （138 men and 68 women, mean aged （59±11） years） who were initially diagnosed as multiple myeloma in Changzheng Hospital （Shanghai, China） and had followup records were enrolled in this study. Potential prognostic factors were evaluated by univariate and multivariate analyses. Four staging systems were applied to compare their suitability for the patients. Results The median survival time of the patients was 33 months. The 1-, 3- and 5-year survival rates were 80.18%, 48.08% and 33.7% respectively. Factors identified as adversely affecting survival were older age, severe bone lesions, low haemoglobin, low platelet, low serum calcium, low serum albumin, high proportion of plasma cells in marrow, high serum creatinine, high serum β2 microglobulin and high C-reactive protein. Among these, only C-reactive protein, β2 microglobulin, albumin and age were the independent prognostic factors. There were statistically significant survival differences among the three groups in Durie Salmon staging system and Bataille staging system, but not in British Medical Research Council staging system or International Staging System. Conclusions High β2 microglobulin, high C-reactive protein, low albumin and old age are independent prognostic factors of multiple myeloma. Bataille staging system appears to be optimal for Chinese multiple myeloma patients.

关键词： multiple myeloma prognosis survival analysis clinical staging system

Self-Assembled DNA/Peptide-Based Nanoparticle Exhibiting Synergistic Enzymatic Activity

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Self-Assembled DNA/Peptide-Based Nanoparticle Exhibiting Syn...

第十届全国化学生物学学术会议

作者： Qing Liu Hui wang Xinghua Shi zhen-gang wang Baoquan Ding CAS Key Laboratory of Nanosystem and Hierarchial Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology

Designing enzyme-mimicking active sites in artificial systems is key to achieving catalytic efficiencies rivaling those of natural enzymes and can provide valuable insight in the understanding of the natural evolution of enzymes. Here, we report the design of a catalytic hemin-containing nanoparticle with self-assembled guanine-rich nucleic acid/histidine-rich peptide components that mimics the active site and peroxidative activity of hemoproteins. The chemical complementarities between the folded nucleic acid and peptide enable the spatial arrangement of essential elements in the active site and effective activation of hemin. As a result, remarkable synergistic effects of nucleic acid and peptide on the catalytic performances were observed. The turnover number of peroxide reached the order of that of natural peroxidase, and the catalytic efficiency is comparable to that of myoglobin. These results have implications in the precise design of supramolecular enzyme mimetics, particularly those with hierarchical active sites. The assemblies we describe here may also resemble an intermediate in the evolution of contemporary enzymes from the catalytic RNA of primitive cells.

关键词： DNA peptide hemin peroxidase mimics self-assembly

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信息技术影响下休闲研究动态与展望

世界地理研究 2017年第3期26卷 167-176页

作者：尹罡甄峰汪侠南京大学地理与海洋科学学院南京210093 湖南城市学院商学院湖南益阳413000 南京大学建筑与城市规划学院南京2100932

作为一种发生在可自由支配时间的任意性活动,休闲既包括人们在其居住地的日常游憩与娱乐活动,也包括人们离开其惯常居住地开展的相关旅游活动。随着经济社会的进步与价值观的转变,休闲的价值内涵正逐步由人们的身心健康扩展至城市居民... 详细信息

作为一种发生在可自由支配时间的任意性活动,休闲既包括人们在其居住地的日常游憩与娱乐活动,也包括人们离开其惯常居住地开展的相关旅游活动。随着经济社会的进步与价值观的转变,休闲的价值内涵正逐步由人们的身心健康扩展至城市居民的生活品质及城市的发展质量。信息与通讯技术(ICT)的迅猛发展给包括休闲在内的人类生产、生活的各个领域带来了广泛和深刻的影响。在上述背景下,本文采用文献信息分析法和对比分析法就信息技术对休闲的影响,从休闲时空行为、休闲产业及休闲研究方法等三个方面进行梳理、分析与总结,结果显示国内外关于信息技术对休闲影响的研究在研究视角、研究方法及研究侧重点上均存在差异。在信息技术支撑的大数据时代,应更多地应用大数据挖掘与分析技术研究人们的休闲行为特征,并在此基础上,分析休闲行为的空间效应及信息技术对不同休闲方式的影响。

关键词：信息技术休闲互联网大数据

聚合物A/B共混理论:相平衡及Coil-to-Globule转变

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聚合物A/B共混理论:相平衡及Coil-to-Globule转变

中国化学会2017全国高分子学术论文报告会

作者：徐玉赐 zhen-gang wang 宁波大学 California Insititute of Technology

Flory-Huggins理论是描述聚合物共混里程碑式的工作,通过假设高分子A/B均匀混合,并用一个唯象的相互作用参数c来表示它们之间的相互作用从而得到体系的自由能。当大于临界c时候,共混体系会分相,形成稀相与浓相两相。但是在稀溶液的情况... 详细信息

Flory-Huggins理论是描述聚合物共混里程碑式的工作,通过假设高分子A/B均匀混合,并用一个唯象的相互作用参数c来表示它们之间的相互作用从而得到体系的自由能。当大于临界c时候,共混体系会分相,形成稀相与浓相两相。但是在稀溶液的情况下,体系真实的物理图像并不是Flory-Huggins所描述的均匀分布,而是具有局部的浓度涨落。我们通过考虑这种局部的浓度涨落,发现在稀溶液的情况下,F-H理论由于假设均匀分布,而过高的估计了体系相互作用能,进而极大的低估了溶解度极限;另一方面,稀相浓度与聚合度N的指数关系也并非为F-H所预测的N,而是N的关系。最后我们对局部涨落单链的Globule-to-Coil转变也进行了研究,发现随着chi的降低,单链分子会经历完全榻缩小球,到表面溶胀,然后再到Coil结构。

关键词： Flory-Huggins Theory Localized Fluctuation Self-Consistent Field Theory Coil-to-Globule Transition