Orientation of photosynthetic reaction center in Langmuir–Blodgett film by formation of cross-linked complex with cytochrome c

Abstract

Cross-linked complex between photosynthetic reaction center and horse heart cytochrome c (cyt c) was prepared for the control of molecular orientation in Langmuir–Blodgett (LB) method. The surface of cyt c is highly hydrophilic whereas that of RC is hydrophobic. A polar distribution of hydrophobicity/hydrophilicity in the complex was realized by the cross-linkage of the different protein molecules. An index was introduced to evaluate the hydrophobicity of the surface of the proteins. The orientation of RCs in an LB film was evaluated by the displacement current. The complex showed a response 1.5 times larger than that of RC.