Bustamante Carlos, Chemla Yann R, Moffitt Jeffrey R
Cold Spring Harb Protoc. 2009 Oct;2009(10):pdb.top60. doi: 10.1101/pdb.top60.
Optical traps or "optical tweezers" have become an indispensable tool in understanding fundamental biological processes. The ability to manipulate and probe individual molecules or molecular complexes has led to a new, more refined understanding of the mechanical properties of the fundamental building blocks of the cell, and of the mechanism by which molecular machines function. The field has seen a steady stream of technological advances that have greatly refined the technique. One major effort has been in developing methods to resolve motions at the angstrom level--the fundamental length scale for many biological processes. This drive has only recently come to fruition with the advent of high-resolution optical trapping techniques that can now detect movements on the scale of a single base pair of DNA, 3.4 A. Here we briefly review the basic concepts and components of optical traps and the single-molecule experiments in which they are used.
光镊，即“光学镊子”，已成为理解基本生物学过程不可或缺的工具。操纵和探测单个分子或分子复合物的能力，使得人们对细胞基本组成部分的力学性质以及分子机器的运作机制有了全新的、更精确的认识。该领域不断涌现出技术进步，极大地完善了这项技术。其中一项主要工作是开发在埃米尺度上解析运动的方法——这是许多生物学过程的基本长度尺度。随着高分辨率光镊技术的出现，这一努力最近才取得成果，现在这种技术能够检测到DNA单碱基对尺度（3.4埃）的运动。在此，我们简要回顾光镊的基本概念和组件，以及使用光镊的单分子实验。
