Studies on Tetrahymena membranes: Modification of surface membrane lipids by replacement of tetrahymanol by exogenous ergosterol in Tetrahymena pyriformis

摘要: Abstract Tetrahymena pyriformis WH-14 cells were grown in the medium supplemented with ergosterol (1 mg/100 ml) and effects of replacement tetrahymanol by upon lipid composition surface membranes (cilia pellicles) examined. 1. 1.|By scanning freeze-etch electron microscopy it was suggested that exogenous would be inserted into regions membranes. Although freeze-etched faces filipin-treated containing native showed a random distribution 85-A protein particles, ergosterol-replaced after same polyene treatment revealed marked ultrastructural alterations on fracture faces. 2. 2.|The induced profound alteration phospholipid class increase phosphatidylethanolamine compensatory decrease phosphatidylcholine 2-aminoethylphosphonolipid. 3. 3.|There are significant quantitative but not qualitative changes fatty acid total lipids from There also increases saturated decreases unsaturated acids. Phosphatidylethanolamine acyl chains particularly become more saturated, as compared two other phospholipids, pellicles. This saturation is due to an appreciable C14 : 0, C16 0 iso-C17 C18 1( Δ 9 ), C 18 2 (Δ 9, 12 ) 3 6, ). 4. 4.|These results suggest phospholipids well their required modify overall membrane for maintenance proper fluidity. Our data support thesis polar head groups involved organization sterols interact selectively molecules appropriate chain biological