Acyl‐Coenzyme A: Cholesterol Acyltransferase

摘要: The preincubation at 37°C of rat liver microsomal fraction, followed by re-isolation the treated vesicles, results in a time-dependent increase activity acyl-CoA: cholesterol acyltransferase. presence cholesterol-phospholipid (1:1, mol/mol) liposomes higher rate and under these conditions is liposomal concentration-dependent. The fraction [3H]cholesterol-phospholipid transfer [3H]cholesterol to re-isolated vesicles this follows first-order kinetics respect donor concentration. These preincubations result also concentration-dependent incorporation into cholesteryl oleate produced on assay acyltransferase activity. From specific radioactivity data esters synthesised preparations, equilibration with substrate pool can be calculated. half-time decreased concentration present during preincubation. activation energy for acyltranferase was 87.9 kJ/mol independent cholesterol. total similar value low concentrations progressively increasing suggest that conditions, temperature-dependent due non-esterified from other and/or contain enzyme therefore increased availability substrate.