PARENT SESSION
Posters P4Aa Chlorophyll and bilin based antenna systems. Abstracts (239-271)

Aggregational states of LHCIIb. Chunhong Yang^{*,1, 2}, Harald Paulsen¹, ¹ Institute of General Botany, Mainz, Germany² Institute of Botany, Beijing, P. R. China

ABSTRACT- Aggregation of light-harvesting chlorophyll a/b complex (LHCIIb) is thought to be involved in some of its functional states. Circular dichroism (CD) and absorption spectra, steady state and time-resolved fluorescence emission spectra have been used to study LHCIIb in different aggregated states embedded in bilayer membranes made of thylakoid lipids. CD spectra showed a chiral structure of LHCIIb aggregates in liposomes. Their size correlates positively with fluorescence quenching at 77K. The effect of different lipids on this correlation was measured to study the effect of different thylakoid lipids on LHCIIb aggregates. The correlation was also influenced by low pH and the presence of zeaxanthin.

KEY WORDS: aggregation, Light harvesting chlorophyll a/b complex, liposome