Single-Molecule Pullers with Improved Force Resolution

描述（由申请人提供）：蛋白质具有许多结构和功能。 从骨骼中的胶原蛋白到肌肉中的肌联蛋白， 从细胞表面的整联蛋白到细胞膜内的离子通道。 最近，已经表明，特殊的原子力显微镜，“拉，” 可用于测量单个分子的机械性能， 拉他们。 来自这些牵引器的力与距离曲线包含以下信息： 分子内的键和分子间的键这些信息 可能会导致更深入地了解与疾病相关的病理学， 蛋白质的结构和机械性质，并提供洞察可能的 补救办法 然而，现有的可用于牵引的牵引器存在问题。 一般用途。例如：1）目前用于牵引机的力噪声 这件作品比它需要的要大得多， 由于弱键的特性。2)现有的牵引机不能将原子力联合收割机 显微镜选择分子的成像能力以及精确的 传感器来测量拉动的距离。其他问题详见 提案的主体。 在此建议开展工作，以改进可用于一般 使用仪器的开发分三个阶段：（1）增加小悬臂梁 提高部队分辨率（5倍）和速度的能力 （30倍），同时保持精确的位置测量和成像，（2） 为具有高数值孔径的显微镜物镜增加光学通路 以及（3）在拉动和成像两者中仅移动悬臂，以避免高 细胞培养物等精细样品的频率振荡。

DESCRIPTION (provided by applicant): Proteins have many structural and mechanical roles in the body from collagen in bones to titin in muscles and from integrin on the cell surface to ion channels within cell membranes. Recently, it has been shown that special Atomic Force Microscopes, "pullers," can be used to measure the mechanical properties of individual molecules by pulling on them. The force vs. distance curves from these pullers contain information about bonds within molecules and about bonds between molecules. This information could lead to a deeper understanding of pathologies associated with the structural and mechanical properties of proteins and give insight into possible remedies. There are, however, problems with the existing pullers that are available for general use. As examples: 1) the force noise in the pullers currently used for this work is significantly larger than it needs to be, obscuring subtle features due to weak bonds. 2) Existing pullers do not combine the Atomic Force Microscope's imaging abilities for selecting molecules together with accurate sensors to measure the distance of pulling. Other problems are detailed in the body of the proposal. Work is proposed here to improve the instruments that are available for general use by three stages of instrument development: (1) adding small cantilever capability for increased force resolution (a factor of 5) and increased speed (a factor of 30) while retaining accurate position measurement and imaging, (2) adding optical access for microscope objectives with high numerical aperture and (3) moving only the cantilever in both pulling and imaging to avoid high frequency shaking of delicate samples like cell cultures.