Good Vibrations for Energy Management in Biomolecules

Primary steps of photo-initiated reactions in biology have been exhaustively investigated in the quest for fundamental principles underpinning energy transfer, conversion and storage at the molecular scale. An understanding of common operational motifs across several light-initiated processes has therefore the potential to advance this scientific area well beyond the state of art.

Over the last decade, ultrafast two-dimensional spectroscopy of photosynthetic light-harvesting antennae has revealed oscillatory electronic dynamics lasting up to picoseconds. Using the same experimental approach, researchers have recently observed picosecond coherent dynamics in photosynthetic reaction centers undergoing light-induced charge separation. The interpretation and implications of these experimental observations are being widely investigated all over the world. An issue that is becoming increasingly clear is that the observed picosecond coherent dynamics in these photosynthetic complexes reflects a non-trivial dynamical interplay between electronic interactions and specific non-equilibrium vibrational motion.

Research has also indicated that the primary energetic process of photo-transduction, for instance in bacteriorodhopsin, involves selected vibrational dynamics of retinal chromophores in their excited electronic states. Moreover, specific vibrational motions have being hypothesized to assist hydrogen transfer in some enzyme-catalyzed reactions as well as to be an integral component in molecular recognition.

The mounting scientific evidence of concerted electronic-vibrational dynamics across a variety of photo-activated processes thus suggests that a possible common fundamental operational principle for energy management in biomolecules is the direct involvement of specific, non-thermal equilibrium vibrational motion in the process of interest.  The aim of this workshop is therefore to gain a better understanding of the principles behind molecular motions assisting effective energy transfer, conversion and storage in photo-activated biomolecules.

Three key questions will be addressed during the workshop:

1)    Which experimental techniques do we need to develop to probe correlated electronic-vibrational dynamics in photo-activated molecules?

2)    What is the functional role of non-equilibrium vibrational motion for energy and charge transport as well as energy storage in biomolecules? How are these specific molecular motions “selected”?

3)    Do we have an appropriate theoretical framework to describe and understand these phenomena? Is the predictive power of the current theories enough to accurately predict dynamics and functionality?