Detergent effects upon the picosecond dynamics of higher-plant light-harvesting chlorophyll complex (LHC2)

Abstract

Resolubilisation of detergent-extracted higher-plant light-harvesting complex (LHC2) from pea thylakoid membranes is shown to produce a sample which is heterogeneous in terms of its aggregation state. The dependence of the degree of aggregation upon the chlorophyll/detergent molar ratio is monitored using the techniques of single-photon counting, circular dichronic absorption spectroscopy and fluorescence spectroscopy. In general, greater aggregation is shown to lead to shorter fluorescence lifetimes and extra exciton features which can be compared with the known symmetry of the crystallised LHC2 previously determined to a resolution of 16 Å.