POLYMER ULTRATHIN FILMS WITH IMMOBILIZED PHOTOSYNTHETIC REACTION-CENTER PROTEINS

Properties of mixed monolayers of lipid-photosynthetic reaction center proteins (RC) were studied and the optimum conditions for stable film s fabrication were determined. The following synthetic: N-acryloylphos phatidylethanolamine (ACPE), tetracosa-11,13-diinoic acid (TDA), penta cosa-10,12-diinoic acid (PDA), dioctadecyldienoylphosphatidylcholine ( DODL) and natural lipids: L-(sic)-phosphatidylethanolamine (PE), L-(si c)-phosphatidylcholine (PC) a ere used. The rate of polymerization of the mixed ACPE-RC and TDA-RC monolayers is lower in comparison with co rresponding values for pure lipid-like monomers on air/water interface . The optical and photoelectrical measurements provide evidence for an orientation of RCs on interface. Hydrophilic H-subunit in monomeric a nd polymeric ACPE-RCs, and monomeric DODL-RCs monolayers is preferenti ally oriented towards water as in the pure RC monolayers. Opposite ori entation was found with TDA-RCs and PDA-RCs films. No preferential ori entation for lipid-RCs from C. aurantiacus monolayers was found becaus e of the RCs having low assymmetry of hydrophobic subunits (M and L).