STUDY OF MONOLAYER AND MULTILAYER MEMBRAN ES OF THE PHOTOSYSTEM-II REACTION CENTERS FROM SPINACH

Monolayers of the photosystem II reaction center (PSIIRC) pigment-prot ein complexes isolated from spinach on the liquid/air interface and th eir multilayers on Ag electrodes were prepared and investigated. The o ptimum conditions for the preparation of stable film monolayers were t he following: 10-mM Tris-HCl buffer (pH 7.0-8.0) as a liquid subphase at 20 degrees C. The monolayers were transferred onto the surface of a n anodized Ag electrode by the Langmuir - Blodgett and Langmuir - Scha efer methods and investigated by the surface-enhanced resonance Raman spectroscopy (SERRS). The SERRS spectra obtained at two excitation wav elengths (406.1 and 488.0 nm) exhibited signals from all the chromopho res (chlorophyll, pheophytin and carotenoides). The obtained results p rove that the native properties of the PSIIRC are preserved in such mo nolayer films and allow some suggestions to be made about the orientat ion of the protein-pigment complexes on Ag electrodes and at the liqui d/air interface.