A study of moss (Marchantia polymorpha) thylakoid membrane lipids in monolayers.

Monolayers of seven fractions of natural lipids (phosphatidyl inositol, sulfoquinovosyl diacylglycerol, phosphatidylcholine, digalactosyl diacylglycerol, phosphatidyl glycerol, phosphatidylethanolamine, monogalactosyl diacylglycerol), isolated from the photoautotrophic cell culture of the moss Marchantia polymorpha grown under normal and light-stress conditions, have been prepared for the first time. We have shown that the high-intensity light affects the area occupied by the lipid molecule. In the case of digalactosyl diacylglycerol and phosphatidyl glycerol fractions, after the light stress the area significantly increased from 0.

[Effect of surfactants on peroxidase activity. II. Effect of cationic surfactants].

The effect of various cationic surfactants on the initial rate of the 5-aminosalicylic acid peroxidation with horseradish peroxidase was studied. With increasing concentration of the surfactant, the rate first increased and then decreased. We attributed these changes to a primary activation of the enzyme and/or an increase in the concentration of the substrate in the region of the active site and to the subsequent inactivation of the protein with surfactant followed by its denaturing, respectively.

Mixed lipid-protein films of bacterial photosynthetic reaction centres. II. Mixed multilayers on solid supports.

Mixed lipid-protein multilayers composed of the reaction centre (RC) proteins from the Chloroflexus aurantiacus and Rhodobacter sphaeroides (wild type) photosynthetic bacteria and synthetic lipids were investigated. The optimal conditions for forming thin films on solid plates (approximately 100% transfer) were 30 mN/m surface pressure and transfer of the interfacial monolayers from the buffer/air interface onto the plates by the Langmuir-Schaefer method. The films transferred onto quartz and optical transparent current-conducting plates retained their optical and photoelectric properties.

Polymer ultrathin films with immobilized photosynthetic reaction center proteins.

Mixed monolayers of lipids with photosynthetic reaction center proteins (RCs) from Rb. sphaeroides and C. aurantiacus were studied and the optimum conditions for stable films fabrication were determined.