基于蛋白质分子自组装体系的构建

蛋白质是一类功能丰富、结构独特的生物大分子,具有高度的自组装特性。氨基酸通过酰胺键形成序列确定的肽链,是蛋白质的基本构成单元。肽链通过弱相互作用控制肽链折叠以及蛋白质高级结构的形成。同时,蛋白质是一种来源丰富、生物可降解以及生物相容性可再生资源,利用蛋白质的自组装特性构建具有生物功能的可控自组装体系是纳米科学、材料科学以及生物医学等学科潜在的研究课题之一。本文从分子科学的角度解析了蛋白质三维结构的自组装特性,进一步探讨蛋白质热变性后自组装、金属诱导的蛋白质自组装、蛋白质与高分子的自组装以及蛋白质杂化体的自组装。旨在进一步认识和理解蛋白质的自组装特性,并为设计和构建结构可控及功能独特的自组装体系提供思路。     

基于生物大分子的纳米药物载体

生物大分子材料由于其可再生性、无毒性以及良好的生物相容性、生物可降解性和黏膜粘附性等特点成为药物载体研究的热点,尤其是将其作为纳米药物载体材料更加受人关注。本文首先对生物大分子纳米颗粒常用的制备方法--乳化法、自组装法和离子凝聚法进行了详细的介绍。由于乳化法在一定程度上破坏了生物大分子的生物相容性,因此自组装法和离子凝聚法是比较理想的制备方法。其中自组装法是利用两亲性的生物大分子,如蛋白质、多糖衍生物等在静电作用、疏水作用、范德华力等非键合作用力下组装成纳米结构;而离子凝聚法则是利用聚电解质与带相反电荷物质之间的静电作用形成纳米结构。接着本文对通过这些方法获得的生物大分子纳米颗粒作为蛋白类药物、抗癌药物以及基因药物的载体在近年来的研究进展进行了归纳和总结,结果显示其在药物缓释体系中具有广阔的应用前景。     

DNA发夹结构自组装信号放大策略应用的研究进展

DNA发夹结构自组装因具有无酶参与、等温以及识别序列能力强等优点,在生物分子和金属离子检测方面展现了良好的发展前景。该文梳理了DNA发夹结构自组装信号放大策略的类型,综述了近年来该策略在致病菌、核酸肿瘤标记物、蛋白质、无机金属离子,以及生物小分子检测中应用的研究进展,并对其未来发展趋势进行了展望,旨在为基于DNA发夹结构自组装检测生物分子提供一定的参考。     

生物大分子自组装膜及其应用研究进展

本文主要介绍了酶，蛋白质、DNA等生物大分子自组装膜的研究进展，并对生物大分子膜在生物传感器，分子器件，高效催化材料，医用生物材料等方面的应用前景进行了展望。     

Langmuir膜及LB膜中的金属参与

本文主要介绍了金属离子与Langmuir膜及LB膜相互作用中静电、配位等作用方式及其对膜相态和分子二维排列的影响。在此基础上探讨了Langmuir膜对金属离子的识别与传感。以Langmuir膜和LB膜为二维模板诱导无机盐定向生长作为金属/单分子膜结合的重要应用在文中也进行了讨论。通过举例展示了金属离子参与的Langmuir膜和LB膜催化有机反应的特点。最后对金属参与的Langmuir膜和LB膜在功能化和器件化等方面的研究也作了论述， 并通过介绍金属螯合类脂分子的Langmuir膜在蛋白质等生物大分子界面定向聚集研究中的应用表明了金属参与的Langmuir膜及LB 膜在生命科学研究中的意义。全文贯穿了金属结合调节Langmuir膜和LB膜组装结构以及通过金属结合导入功能基团进行有序组装的思想。     

自然的启示:多糖与功能材料的集成组装(英文)

从自然界汲取创新灵感,深层次解析生物材料的形成过程以及结构-功能关系是仿生材料研究的核心问题。生物矿物质是一类天然无机-有机界面复合材料,以复杂高级有序结构、多功能以及温和组装为特点,在复合生物大分子诱导调控下构建而成。天然多糖是一类特殊的碳水化合物,具有丰富的化学和结构特性,它们在众多生物矿物质的形成过程中扮演重要角色。科学家预言多糖在创新功能材料研究中举足轻重。文章以贝壳珍珠层、龙虾壳及硅藻为例,概述生物矿物质的形成过程和结构-功能关系,列举仿生先进材料研究代表性工作,扼要介绍多糖自组装特性、生物功能以及无机-多糖共组装化学,并列举该研究领域代表性前沿工作,评述多糖自组装体诱导构建功能界面材料的研究战略,提出对该研究领域未来发展的粗浅看法。期望以此文抛砖引玉,邀请跨学科合作,推动功能材料集成组装研究领域的发展。     

非共价键胶束方法与原理的拓展与应用

20世纪末,江明等在其有关大分子络合的研究基础上,通过将大分子间相互作用局域化,成功地利用大分子间的络合来驱动结构规整组装体的形成.这一思想和方法通过不断地拓展和深化,形成了大分子自组装的新路线,获得了一系列具有新颖结构与功能的核壳间为非共价键连接的聚合物胶束(non-covalently connected micelles,NCCM).本综述将对近年来我们在非共价键胶束方法与原理的拓展与应用方面取得的成果作一总结.内容包括:为NCCM的形成引入新的驱动力,并同时赋予NCCM新的性质与功能;将NCCM的形成原理应用于生物大分子的自组装,发展出了全绿色的大分子自组装路线;运用将相互作用局域化的基本思想,将嵌段共聚物的化学交联反应局域化,发展出化学交联诱导嵌段共聚物胶束化的新方法.     

诱导配体：蛋白质组装新策略

近年来,分子自组装的研究特别关注应用复杂组装基元模拟体内复杂的生命过程.其中,利用蛋白质作为组装基元构筑组装体的相关研究有助于进一步了解生命相关的自组装,并进一步揭示生命过程的调控机制.然而,由于蛋白质组装基元自身的结构复杂性和构象多样性等特点,具有规则结构的人工蛋白质组装体仍然难以构建.本文将回顾和总结本课题组近年来所提出的诱导配体蛋白质组装新策略.首先简要叙述文献中蛋白质组装方向的研究进展,继而介绍诱导配体策略产生的背景和主要思路,重点讨论利用诱导配体策略获得的蛋白质组装体的结构、形貌及功能,最后展望该策略的发展前景.     

酪氨酸衍生物调控酶催化路径可控合成功能黑色素

利用酶催化自组装将生物小分子构筑成具有独特功能的生物大分子聚合物是制备功能生物材料极具前景的新策略,然而其挑战在于如何在底物层面调控生物大分子的结构和功能.以从酪氨酸构筑黑色素为例,通过底物结构的简单衍生化,实现了对酶催化自组装过程中关键聚合位点的控制,得到一系列尺寸、形貌各异的黑色素产物.进一步表征了各黑色素产物的光热转换性能,在细胞层次验证了结构修饰的黑色素用于光热材料的潜力.揭示了通过改变底物核心基团周边化学结构调控酶催化路径,进一步调控黑色素产物性质及功能的可行性,为构筑新型功能黑色素材料提供了新思路,同时对揭示生物大分子结构与生物功能的关系提供了有益启示.     

蛇毒蛋白质中金属离子及其配位化学的研究

蛇毒蛋白质中金属离子及其配位化学的研究刘清亮吴双顶张祖德余华明（中国科学技术大学应用化学系安徽合肥２３００２６）在生命体内，金属离子能参与许多重要的生物化学反应，其实质就是金属离子与生物大分子的相互作用。蛇毒可以用作药物，具有抗凝、止血、抗癌和镇痛等...     

Self‐Assembled Cyclic Structures from Copper(II) Peptoids

Metal–ligand coordination is a key interaction in the self‐assembly of both biopolymers and synthetic oligomers. Although the binding of metal ions to synthetic proteins and peptides is known to yield high‐order structures, the self‐assembly of peptidomimetic molecules upon metal binding is still challenging. Herein we explore the self‐assembly of three peptoid trimers bearing a bipyridine ligand at their C‐terminus, a benzyl group at their N‐terminus, and a polar group (N‐ethyl‐R) in the middle position (R=OH, OCH₃, or NH₂) upon Cu²⁺ coordination. X‐ray diffraction analysis revealed unique, highly symmetric, dinuclear cyclic structure or aqua‐bridged dinuclear double‐stranded peptoid helicates, formed by the self‐assembly of two peptoid molecules with two Cu²⁺ ions. Only the macrocycle with the highest number of intermolecular hydrogen bonds is stable in solution, while the other two disassemble to their corresponding monometallic complexes.     

Self‐Assembly of Giant Spherical Liquid‐Crystalline Complexes and Formation of Nanostructured Dynamic Gels that Exhibit Self‐Healing Properties

Supramolecular self‐assembly of 24 forklike mesogenic ligands and 12 transition metal ions led to the formation of giant spherical coordination complexes that exhibit liquid‐crystalline (LC) phases. Self‐healing LC supramolecular gels were also obtained through the introduction of these LC nanostructured supramolecular giant spherical complexes into dynamic covalent networks formed by cross‐linkers and bifunctional polymers. The giant spherical structures of the Pd^II complexes with 72 rodlike moieties on the periphery were characterized by NMR, diffusion‐ordered NMR spectroscopy, and mass spectrometry. These complexes are stable and exhibit lyotropic LC behavior, while the mesogenic ligands show thermotropic LC properties. The self‐assembled LC structures of the spherical complexes can be tuned by the length of the rodlike moieties.     

Salen‐Based Amphiphiles: Directing Self‐Assembly in Water by Metal Complexation

Tuning morphologies of self‐assembled structures in water is a major challenge. Herein we present a salen‐based amphiphile which, using complexation with distinct transition metal ions, allows to control effectively the self‐assembly morphology in water, as observed by Cryo‐TEM and confirmed by DLS measurements. Applying this strategy with various metal ions gives a broad spectrum of self‐assembled structures starting from the same amphiphilic ligand (from cubic structures to vesicles and micelles). Thermogravimetric analysis and electric conductivity measurements reveal a key role for water coordination apparently being responsible for the distinct assembly behavior.     

Self‐assembly of a Sequence‐shuffled Short Peptide Amphiphile Triggered by Metal Ions into Terraced Nanodome‐like Structures

We highlight the structural diversity of strategically designed two short peptide amphiphiles (sPAs) and describe their structure–function relationship studies. The shuffling of two key amino acids, that is, tyrosine and phenylalanine, in a designed sPA lead to a pair of constitutional isomers. Such small and strategic alteration can bring a substantial change in the self‐assembling pattern. Inspired from the naturally occurring metallopeptides, bioactive transition‐metal ions were used for constructing the unusual nanostructures. Use of appropriate metal ions created bigger differences between the properties of these isomers and hence the self‐assembly. Coordination of appropriate transition metal ions modifies the internal nanoscale structures of sPA, thus leading to the formation of vertically stacked terraced layers with decreasing size, which possess a high degree of dimensional regularity. We propose that such metal‐induced terraced nanodome‐like hierarchical self‐assembly may have relevance for specific biotechnology applications.     

几种环状多肽的几何构型特征及其自组装的理论研究

运用半经验分子轨道AM₁方法优化了6种环状多肽的结构,并进行了振动分析的确认.通过对它们的能量、结构特征和正则振动模式的分析研究,揭示了这类分子具有能够进行自组装过程的结构特征,详细讨论了取代基对结构和自组装过程的影响.     

Self‐assembly: An intriguing relationship between structures of metal complexes and shapes of ancient Chinese characters

Self‐assembly is a fundamental principle, which generates structural organization on all scales from molecules to galaxies. In the field of chemistry and materials science, the self‐assembly process driven by noncovalent interactions offers considerable advantages over the stepwise bond formation in the construction of large supramolecular assemblies with different sizes and shapes. The structures of metal clusters are mainly constructed from the assembly of mononuclear metal center to dinuclear, trinuclear species, and so on. It is of interest that Chinese ancient people also used this concept to create and encrypt characters. Herein, we report on an intriguing relationship between structures of metal complexes and the shapes of ancient Chinese characters, in which the self‐assembly principle is clearly demonstrated.     

芳基柔性二齿配体在金属超分子自组装中的结构调控作用

芳基柔性二齿佤体的配位构型多变，使得其金属配合物的结构丰富多彩。该文介绍了15种该类配体及其相应的金属配合物的结构与性质和自组装策略，对其在超分子自组装中的结构调控作用作了概述。     

Spin‐Übergänge in supramolekularen Strukturen. Für Speicherbausteine von morgen?

We reported about octahedrally coordinated Fe2+‐complexes, which are able to switch between two stable spin states (LS and HS) with different magnetic properties. This phenomenon is called spin crossover (SCO). The interaction between metal ion and ligand determines the actual spin state and whether an extern stimulus can trigger a spin crossover. Due to this fact it is possible for the chemist through the choice of the ligands to manipulate the character and the temperature region of the SCO. Some metal complexes assemble into highly ordered structures on graphite by molecular self assembly. The substitution of the metal complexes with alkyl chains and the interaction of these chains with the highly ordered graphite is crucial for a periodic arrangement of the complexes on the surface. For the future we are curious to see whether through the cooperative effort of coordination chemistry (SCO phenomenon) and surface science (self assembly of SCO complexes on a surface) the vision of a molecular memory will turn into a reality.     

Triple Self‐Sorting in Constitutional Dynamic Networks: Parallel Generation of Imine‐Based CuI,FeII, and ZnII Complexes

Three imine‐based metal complexes, having no overlap in terms of their compositions, have been simultaneously generated from the self‐sorting of a constitutional dynamic library (CDL) containing three amines, three aldehydes, and three metal salts. The hierarchical ordering of the stability of the three metal complexes assembled and the leveraging of the antagonistic and agonistic relationships existing between the constituents within the constitutional dynamic network corresponding to the CDL were pivotal in achieving the sorting. Examination of the process by NMR spectroscopy showed that the self‐sorting of the Fe^II and Zn^II complexes depended on an interplay between the thermodynamic driving forces and a kinetic trap involved in their assembly. These results also exemplify the concept of “simplexity”—the fact that the output of a self‐assembling system may be simplified by increasing its initial compositional complexity—as the two complexes could self‐sort only in the presence of the third pair of organic components, those of the Cu^I complex.     

铜(Ⅱ)离子导向的自组装研究

A few copper(Ⅱ) ions or groups have been designed and investigated for metal-assisted self assembly. Reactions of these metal units with a number of linear bridging ligands have led to the production of some dinuclear copper(Ⅱ) complexes and coordination polymers in which metal centers are all five-coordinate in the configuration of a square pyramid or a triangular bipyramid.