How does life interact with light? Photo-fragmentation and photo-electron spectroscopy of biochrompohores

Dr. Y. Toker / Institute of Physics and Astronomy, Aarhus University, Denmark

*current Address: Department of Particle Physics, The Weizmann Institute of Science

Biochromophores are the molecules used by living organisms in order to interact with visible light. Naturally these molecules are found within proteins, however in order to arrive at a fundamental understanding of their basic properties, our approach is to study the chromophores isolated from their surroundings using action spectroscopy. Recent photo-electron spectroscopy measurements of the Green Flourescent Protein chromophores will be presented, revealing and interesting competition between the different quantum paths available to the chromophore after photo-excitation; as well as photo-fragmentation studies of the Retinal chromophore. These results illustrate the power of action spectroscopy, not only in measuring the absorption bands of isolated ions, but also in studying the dynamics and thermodynamics of these intriguing systems.