Plant viruses for three dimensional actuators

生物系统通常表现为自组装形成复杂的结构。如果复杂的纳米和微结构可以通过自组装来减少生产时间和成本，那么在技术应用方面也会很有兴趣。在这个项目中，将分析和利用基因工程植物病毒的自组装。植物病毒的表面性质可以进行很大程度的修饰，并表现出良好的结晶性能。在重组病毒衣壳的表面，可以呈现出与金属或金属离子具有特异性相互作用的分子，例如与钴、镍离子的组氨酸标签或与金、银的半胱氨酸。然而，在技术应用方面，尽管具有良好的结晶特性，但到目前为止，在坚硬的表面上还不能形成延伸的二维晶体。然而，对球形番茄丛生矮化病毒的初步试验，结果表明，通过基因工程可以呈现正负电荷的氨基酸链，可以形成相当大的二维晶体。在本项目中，这一增长将进一步优化，因此将建立更复杂的结构。特别是，镍离子和组氨酸之间的联系将通过几种方式进行阐述。这包括病毒与底物的结合以及病毒表面的修饰，例如通过组氨酸和其他侧链介导的金属化。此外，外衣壳表面的新功能将得到证实，并将建立用于装载不同化合物的衣壳的系统。我们的总体目标一方面是更深入地了解(修饰的)球形病毒自组装过程中的基本原理。另一方面，我们希望探索可能的应用，特别是那些对有序金属阵列感兴趣的应用，例如在等离子激元或自旋电子学中。

Biological systems commonly show selfassembly to form complex structures. It would be also of interest for technical applications, if complex nano- and microstructures could be produced by selfassembly to reduce production time and costs. In this project the selfassembly of genetically engineered plant viruses will be analyzed and utilized. The surface properties of plant viruses can be modified to a large extent and they show good crystallization properties. On the surface of recombinant viral capsids, molecules can be presented which show specific interactions with e.g. metals or metal ions, such as His-tags with Co and Ni ions or cysteins with Au and Ag. However, for technical applications up to now, no extended two-dimensional crystals can be formed on hard surfaces despite of the good crystallization properties.Preliminary tests with spherical tomato bushy stunt viruses, genetically engineered to present either positively or negatively charged amino acid chains, resulted, however, in the formation of two-dimensional crystals in considerable size. In the present project this growth will be further optimized and in consequence more complex structures will be established. In particular the link between Ni ions and histidin will be exlpoited in several ways. This comprises the binding of the virus to the substrate as well as the modification of the virus surface, e.g. through metallization mediated by histidin and other side chains. In addition, new functionalizations of the outer capsid surface will be proven and systems for the loading of the capsid with different compounds iwill be established.Our general objective is on the one hand the deeper understanding of the underlying principles in the selfassembly process of (modified) spherical viruses. On the other hand we want to explore possible applications, in particular those, in which ordered arrays of metals are of interest, e.g. in plasmonics or spintronics.