STRUCTURE OF AMORPHOUS METAL-HALOGEN BIOMATERIALS IN ARTHROPOD TOOLS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 我们建议使用X射线吸收光谱来表征金属卤素生物材料，这些材料是在大多数节肢动物和其他一些门的角质层工具中生物合成的。这些角质层工具(牙齿、刺、下巴、爪子等)的成熟涉及过渡金属(锰、铁、铜、锌)和卤素(氯、溴、碘)在非晶态结构中的迁移和沉积，X射线衍射无法表征这些结构。我们希望在这些工具的生物合成和成熟过程中，在确定这些生物材料的结构和空间分布方面发现新的生物学、生物化学和材料化学。大量的XAS，然后是成像和X射线显微镜将允许进行详细的结构分析。这些实验的范围从简单的(荧光激发的过渡金属块状X射线吸收光谱)到挑战性的(微米空间分辨率的低能量成像)，都将利用SPEAR3的光束线开发。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We propose to use x-ray absorption spectroscopy to characterize the metal-halogen biomaterials that are biosynthesized in the cuticular tools of most arthropods and a few other phyla. Maturation of these cuticular tools (fangs, stings, jaws, claws, etc.) involves the transport and deposition of transition metals (Mn, Fe, Cu, Zn) and halogens (Cl, Br, I) in amorphous structures that cannot be characterized by x-ray diffraction. We expect to uncover new biology, biochemistry, and materials chemistry in determining the structures and spatial distribution of these biomaterials during biosynthesis and maturation of these tools. Bulk XAS, followed by imaging and x-ray microscopy will allow detailed structural analysis. These experiments range from the straightforward (transition metal bulk XAS by fluorescence excitation) to the challenging (low-energy imaging at micron spatial resolution) that will take advantage of beamline developments for SPEAR3.