| Abstract: | Chromatography of a mixture of phospholipids and Ca-dependent ATPase from sarcoplasmic reticulum solubilized by cholate on a column with anionite results in a formation of proteoliposomes. Using the freeze-fracture technique, it was shown that the density of intramembrane particles in fractured proteoliposomes formed is reversely proportional to the lipid--protein ratio. This is indicative of possible changes in ATPase concentration in the membrane, when the above-mentioned method was used. It was shown that dilution of ATPase with phospholipids increases its thermal stability. This is probably due to aggregation of the ATPase molecules and increase in the length of the borderline of lipids around each enzyme molecule. |
