ISBN 9783843902809

978-3-8439-0280-9, Reihe Physikalische Chemie

Gregor Heiss
Single-Molecule Microscopy Study of Nano-Systems: From synthetic photo-switchable nano-devices to the dynamics of naturally occurring transcription factors

181 Seiten, Dissertation Ludwig-Maximilians-Universität München (2011), Softcover, A5

Zusammenfassung / Abstract

In this work, techniques were developed and used to study the properties of molecules on a single-molecule level. Single-molecule techniques have the major advantage, that in contrast to ensemble measurements, they allow a detailed insight on the distribution and dynamics of single molecules without averaging over subpopulations. The use of Total Internal Reflection Fluorescence Microscopy (TIRFM) in combination with single-pair Förster Resonance Energy Transfer (spFRET) and Alternating Laser Excitation (ALEX) allows the identification of molecular-states by making quantitative measurements of distances in the Ångström range. The development of highly sensitive photon detectors and the use of versatile labeling techniques with photostable (synthetic or genetically-encoded) fluorophores, extended the application of TIRF microscopy to in vitro and live-cell experiments. Despite reducing the complexity of biological systems down to the single-molecule level, functions of individual molecules and interactions between them can be very sophisticated and challenging to analyze. Using information theory based methods, e.g. HMM, the dynamics extracted from single-molecule data was used to illuminate protein interactions and functions.