Theory of optical spectra of photosynthetic pigment-protein complexes: From structure to function

Univ.-Prof. Dr. Thomas Renger

Dec. 16, 2009, 4:15 p.m. HF 9901

In photosynthesis the light energy absorbed by so-called antenna pigment-protein complexes is transferred to the photosynthetic reaction center where it is converted into chemical energy. An important open question is: How does the protein trigger excitation energy transfer? The latter can occur with nearly hundred percent quantum efficiency.

To address this question, a dynamical theory of optical spectra is combined with a structure-based electrostatic/quantum chemical computation of the parameters of the theory. The methods are applied to photosynthetic pigment-protein complexes of green sulfur bacteria and cyanobacteria. Quantitative agreement of the calculated optical spectra with the experimental data is obtained allowing to analyse the structure-function relationships in detail.