[Possible role of acetyl-CoA-carboxylase in biosynthesis of mevalonic acid and sterols in rat liver].
Effect of citrate on acetyl-CoA incorporation into mevalonic acid, sterols and fatty acids after preliminary incubation of rat liver extracts under conditions optimal for acetyl-CoA carboxylase activation, was studied. 30 min preincubation with the citrate at 37 degrees C results in a 2--3-fold stimulation of the mevalonic acid biosynthesis from acetyl-CoA in the microsomal and soluble (140 000 g) fraction, and in that of sterols precipitated by digitonin or isolated by TLC in the mitochondria--free fraction. 2-14C-malonyl-CoA incorporation into the mevalonic acid and sterols and biosynthesis of sterols from 2-14C-mevalonic acid were not stimulated under those conditions. A correlation was shown to exist between the activity of acetyl-CoA carboxylase and the rate of acetyl-CoA incorporation into mevalonate and sterols; the activity of beta-hydroxy-beta-methylglutaryl-CoA reductase, limiting the rate of the sterol biosynthesis, was not changed. The stimulating effect of citrate was found to depend on the concentration of acetyl-CoA and NADPH in the medium. The data obtained suggest that the mevalonic acid biosynthesis in rat liver may occur in the presence of acetyl-CoA carboxylase through the formation of malonyl-CoA.
D000103:Acetyl-CoA Carboxylase / Q000378:metabolism*; D000818:Animals; D002250:Carbon Radioisotopes; D002262:Carboxy-Lyases / Q000378:metabolism; D002784:Cholesterol / Q000096:biosynthesis; D002951:Citrates / Q000494:pharmacology; D005227:Fatty Acids / Q000096:biosynthesis; D006903:Hydroxymethylglutaryl CoA Reductases / Q000378:metabolism; D007553:Isotope Labeling; D007810:Lanosterol / Q000096:biosynthesis; D008025:Ligases / Q000378:metabolism*; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008297:Male; D008798:Mevalonic Acid / Q000096:biosynthesis*; D009243:NAD / Q000494:pharmacology; D009249:NADP / Q000494:pharmacology; D051381:Rats; D013261:Sterols / Q000096:biosynthesis*; D013268:Stimulation, Chemical; D013347:Subcellular Fractions / Q000378:metabolism*
D002250:Carbon Radioisotopes; D002951:Citrates; D005227:Fatty Acids; D013261:Sterols; D009243:NAD; D007810:Lanosterol; D009249:NADP; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases; D002262:Carboxy-Lyases; D008025:Ligases; D000103:Acetyl-CoA Carboxylase; D008798:Mevalonic Acid
O vozmozhnom uchastii atsetil-KoA-karboksilazy v biosinteze mevalonovoĭ kisloty i sterinov v pecheni krysy.