Hierarchical Architecture of Sponge Spicules: Bio-inspired assembly of multifunctional structures by biocatalytically active and structure-guiding proteins

海绵针的层次结构：通过生物催化活性和结构引导蛋白进行多功能结构的仿生组装

• 批准号: 128306461
• 负责人: Professor Dr. Heinz C. Schröder
• 金额: --
• 依托单位: Department Chemie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/128306461?language=en
• 关键词: Hierarchical; Architecture; Sponge; Spicules; Bio

The hierarchically structured skeletons of the siliceous sponges, the Demospongia and the Hexactinellida (glass sponges), and of the calcareous sponges, the Calcarea, with their exceptional opto-mechanical properties have turned out to be excellent models for biomimetic approaches. The biosilica of the siliceous sponges is formed by a unique group of enzymes, the silicateins, that turned out to show both biocatalytic and structure-guiding/forming activity. The species-specific 3D structure of their skeleton is controlled both on gene level, by a sequential gene expression of silicatein and silicatein interacting proteins, and by the specific interaction and assembly of these proteins to filamentous structures, as well as by cellular processes. In the first funding period, fundamental insights have been gained in the inorganic-organic hybrid structure of the spicules and in the mechanism of biosilica formation which was unequivocally proven to occur enzymatically. In the second funding period, new silicatein interactors (silintaphins) have been discovered and functionally characterized, allowing an understanding of the regulation not only of silicatein assembly/activity but also of the formation of the extracellular cylinder-like organic scaffold guiding the longitudinal and appositional growth of the spicules. Moreover, the processes of syneresis and hardening/ageing of the enzymatically formed soft biosilica to solid silica rods have been demonstrated for the first time, opening new avenues for biomimetic/bio-inspired applications of sponge biosilica. In the third period, we will use these tools for the generation of hierarchically structured and multifunctional nanomaterials, applying bio-inspired molecular switches and mimicking precision biosilica molding processes realized in sponges in nature. Among others, the effect of silicatein on the formation of CaCO3/silicatein hybrid fibers (synthetic spicules) shall be studied. The close collaboration between groups from inorganic chemistry and molecular biology shall allow it to exploit the self-assembly, structure-directing and biocatalytic capabilities of the sponge proteins involved in biomineralization, along with nanoparticles of calcium carbonate and metal oxides, for the generation of biomimetic nanostructured materials with new property combinations, whose mechanical and optical properties shall be examined as a function of their composition.

硅质海绵、Demospongia和Hexactinellida（玻璃海绵）以及钙质海绵、Calcarea的分级结构骨架，凭借其特殊的光学机械性能，已成为仿生方法的优秀模型。硅质海绵的生物二氧化硅是由一组独特的酶，即silicateins形成的，结果显示出生物催化和结构引导/形成活性。其骨骼的物种特异性3D结构在基因水平上受到控制，通过silicatein和silicatein相互作用蛋白的顺序基因表达，以及通过这些蛋白质与丝状结构的特异性相互作用和组装，以及通过细胞过程。在第一个资助期内，在针状体的无机-有机混合结构和生物二氧化硅形成机制方面获得了基本的见解，生物二氧化硅的形成机制已被明确证明是酶促作用。在第二个资助期，新的silicatein interactors（silintaphins）已被发现和功能特性，允许的调节不仅silicatein组装/活动的理解，但也形成的细胞外圆柱状有机支架引导纵向和并列生长的骨针。此外，酶促形成的软生物二氧化硅到固体二氧化硅棒的脱水收缩和硬化/老化过程首次得到证实，为海绵生物二氧化硅的仿生/生物启发应用开辟了新的途径。在第三阶段，我们将使用这些工具来生成分层结构和多功能纳米材料，应用生物启发的分子开关，并模仿在自然界中海绵中实现的精确生物二氧化硅成型过程。其中，应研究硅酸盐对CaCO 3/硅酸盐混杂纤维（合成针状体）形成的影响。无机化学和分子生物学小组之间的密切合作将使其能够利用生物矿化中涉及的海绵蛋白质的自组装、结构导向和生物催化能力，沿着碳酸钙和金属氧化物的纳米颗粒，用于产生具有新性能组合的仿生纳米结构材料，其机械和光学性能应作为其组成的函数进行检查。