In nature, bundles of biological fibers are a common solution for many mechanical tasks. Because they exhibit unusual mechanical properties and a stunning adaptability to changing requirements, they are also of interest to the field of nanotechnology. One example of a fiber bundle in biology are microtubules which are essential for a variety of cell functions. They are tubular protein filaments which consist of parallel filaments whose interactions determine the mechanics of the overall microtubule. In nature, the exact architecture of microtubules is tightly controlled for each cell type.
Some of the most drastic mechanical consequences of the fiber architecture are expected to predominantly affect very short microtubules. These predictions have however been difficult to verify because the short length regime is barely accessible to measurements with conventional techniques. In the proposed research, we will employ a high speed, high resolution position detection system based on the scattering of laser light which will allow for measurements in the previously inaccessible microtubule length regime. The thermal fluctuations of microtubules will be exploited to extract their mechanical properties. In addition, the project will study the connection between the number of constituent filaments and the emergent mechanical properties. Results will be compared to state-of-the-art polymer models.
The proposed research aims to identify and quantify the interplay between microtubule molecular architecture and mechanics. The results will not only allow for a deeper understanding of how cellular functions are implemented on a molecular scale, but will also yield insights into nanotechnology because they can be generalized to other fiber bundles, including artificial ones. The gained knowledge may lead to new artificially designed materials available to consumers.
The research will expose students to a rich interplay between scientific fields as diverse as theoretical physics, biochemistry, molecular biology, engineering and material science, thereby training them in developing an interdisciplinary approach towards research.
