Protein-mineral interactions at the organic-inorganic interface in biominerals

生物矿物质中有机-无机界面的蛋白质-矿物质相互作用

• 批准号: RGPIN-2022-03238
• 负责人: McKee, Marc
• 金额: $ 4.08万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=750712
• 关键词: Protein; mineral; interactions; organic; inorganic

Bones, teeth, otoconia, eggshells, snail shells, sea shells, corals, and many other biomineralized structures arise from synergistic interactions between co-existing organic (usually proteins) and inorganic mineral (often calcium-based) phases. These interactions produce hard, composite biological materials having specialized properties, largely attributable to hierarchically organized, supramolecular assemblies that provide a framework for remarkable biomineralized architectures. Negatively charged proteins within this organic framework (the extracellular matrix) may stabilize amorphous mineral precursor phases, or they may attain regulatory chemical complementarity by binding to lattice calcium at the organic-inorganic interface - mechanisms that influence crystal growth processes. It is hypothesized that the molecular precision of such organic-inorganic interfacial interactions regulates crystal growth to produce such hardened, biomineralized composite structures. My NSERC DG biomineralization research program focuses on specific biomolecules and proteins/peptides (notably osteopontin) that regulate calcium carbonate mineral growth (specifically here, the forms calcite and vaterite). Small biomolecules, amino acids, peptides and full-length proteins guide and regulate biomineralization. A common theme for calcium carbonate mineralization is that nanoparticles form within a confined, protein/peptide-rich reaction nanoenvironment, from which they crystallize and align over many length scales to build mesocrystals having occluded organics. This notion contrasts with classical crystallization theory which postulates ion-by-ion attachment. My biomineralization research program compares these scenarios by exploring fundamental principles of how relevant organics influence biomineralization. The short-term objectives for this proposal are to continue examining the extracellular regulatory mechanisms guiding Ca-carbonate biomineralization through three projects: i) reptile (gecko and snake) eggshell structure, ii) the interface (attachment) of avian and reptilian eggshell membrane fibers with the mineral of the shell, and iii) the determinants of synthetic, chiral helicoidal vaterite suprastructure growth (including simulations). Long-term objectives are to explore i) how diverse biomolecules influence Ca-carbonate growth and hierarchical assembly, and ii) how biomineral curvature (vs angulated facets) is produced in biology, particularly in shells. With new information from this research, we will understand key elements of biomineralization biology for calcium carbonate (particularly in eggshells, with implications for food safety in the case of the table egg) that might well cross over into other biomineralizing systems. Such a cross-over may potentially allow for tunable mineralization events in synthetic biomaterials with uses in tissue repair and tissue engineering applications, and for novel chiral materials with unique optical properties.

骨骼、牙齿、耳石、蛋壳、蜗牛壳、海壳、珊瑚和许多其他生物矿化结构是由共存的有机(通常是蛋白质)和无机矿物(通常是基于钙的)相之间的协同作用产生的。这些相互作用产生了具有特殊性质的硬质复合生物材料，这在很大程度上要归因于分级组织的超分子组装，这些组装为非凡的生物矿化结构提供了框架。这种有机骨架(细胞外基质)中带负电荷的蛋白质可能稳定无定形矿物前体相，或者它们可能通过与有机-无机界面上的晶格钙结合来实现调节性的化学互补--这是影响晶体生长过程的机制。据推测，这种有机-无机界面相互作用的分子精度调节晶体生长，以产生这种硬化的、生物矿化的复合结构。我的NSERC DG生物矿化研究项目专注于特定的生物分子和蛋白质/多肽(特别是骨桥蛋白)，它们调节碳酸钙矿物的生长(特别是方解石和球土)。生物小分子、氨基酸、多肽和全长蛋白质引导和调节生物矿化。碳酸钙矿化的一个共同主题是，纳米颗粒在一个受限的、富含蛋白质/多肽的反应纳米环境中形成，从这个纳米环境中，它们结晶并在许多长度尺度上排列，形成具有封闭有机物的介晶。这一概念与经典结晶理论形成鲜明对比，经典结晶理论假定离子与离子之间存在相互作用。我的生物矿化研究项目通过探索相关有机物如何影响生物矿化的基本原理来比较这些情景。这项建议的短期目标是通过三个项目继续研究指导碳酸钙生物矿化的细胞外调控机制：i)爬行动物(壁虎和蛇)蛋壳结构，ii)鸟类和爬行动物蛋壳膜纤维与贝壳矿物的界面(附着)，以及iii)合成的手性螺旋球状球石超结构生长的决定因素(包括模拟)。长期的目标是探索i)不同的生物分子如何影响碳酸钙的生长和分级组装，以及ii)生物矿物的曲率(VS角度面)是如何在生物学中产生的，特别是在贝壳中。有了这项研究的新信息，我们将了解碳酸钙生物矿化生物学的关键要素(特别是在蛋壳中，对餐桌鸡蛋的食品安全有影响)，这些要素很可能会跨越到其他生物矿化系统。这种交叉可能潜在地允许用于组织修复和组织工程应用的合成生物材料中的可调矿化事件，以及具有独特光学性质的新型手性材料。