Effect of Chiral Aggregate of Lutein on Photosynthetic Electron Transport Activity in Spinach Thylakoid, and Interaction between Lutein and Thylakoid Membrane

A herical chiral aggregate of lutein, considered to be an electron conductor, inhibits photosynthetic electron transport (photoreduction) activities in PS I and PS II. Lutein dispersed in thylakoid suspension was incorporated into thylakoid membrane to form the same chiral aggregate as that originally contained in thylakoid. Such a chiral aggregate exhibited different CD patterns from the ordinary one in aqueous system. The residual lutein in the suspension will form the ordinary chiral aggregate which adheres on to the membrane to make up by-path of electron transport. The results indicate an apparent inhibition of photoreduction activities in presence of added lutein.