Measurements on Single DNA Molecules

All our understanding of how DNA works is based on evidence obtained with bulk methods. Moreover, information on the detailed conformation of DNA and interactions between DNA and proteins at a high resolution, have been obtained almost entirely under highly nonphysiological conditions (vacuum, low temperature etc.). Recently several methods have become available that make it possible to study individual bio-molecules under physiological conditions. We will describe three of these methods and there application to DNA research: flow analysis of individual molecules, measuring mechanical forces of bio-molecules using optical tweezers and using an AFM to study the dynamics of DNA and DNA protein interactions