Weill Cornell Medicine, Department of Anesthesiology, 1300 York Avenue, New York, NY, 10065, USA.
Weill Cornell Medicine, Department of Physiology and Biophysics, 1300 York Avenue, New York, NY, 10065, USA.
Nat Commun. 2018 Nov 26;9(1):4983. doi: 10.1038/s41467-018-07512-3.
Dynamics are fundamental to the functions of biomolecules and can occur on a wide range of time and length scales. Here we develop and apply high-speed AFM height spectroscopy (HS-AFM-HS), a technique whereby we monitor the sensing of a HS-AFM tip at a fixed position to directly detect the motions of unlabeled molecules underneath. This gives Angstrom spatial and microsecond temporal resolutions. In conjunction with HS-AFM imaging modes to precisely locate areas of interest, HS-AFM-HS measures simultaneously surface concentrations, diffusion coefficients and oligomer sizes of annexin-V on model membranes to decipher key kinetics allowing us to describe the entire annexin-V membrane-association and self-assembly process in great detail and quantitatively. This work displays how HS-AFM-HS can assess the dynamics of unlabeled bio-molecules over several orders of magnitude and separate the various dynamic components spatiotemporally.
动力学是生物分子功能的基础，并且可以在广泛的时间和长度尺度上发生。在这里，我们开发并应用了高速原子力显微镜高度谱（HS-AFM-HS）技术，通过该技术，我们可以监测固定位置的 HS-AFM 探针的感应，以直接检测下方未标记分子的运动。这提供了埃分辨率的空间和微秒分辨率的时间。结合 HS-AFM 成像模式来精确定位感兴趣的区域，HS-AFM-HS 同时测量模型膜上 annexin-V 的表面浓度、扩散系数和低聚物大小，以解析关键动力学，使我们能够详细和定量地描述 annexin-V 膜结合和自组装过程的整个过程。这项工作展示了 HS-AFM-HS 如何评估未标记生物分子的动力学，并在时空上分离各种动态成分。
