An investigation into the role of malonyl-coenzyme A in isoprenoid biosynthesis.
1. [(14)C]Malonyl-CoA was incorporated into isoprenoids by cell-free yeast preparations, by preparations from pigeon and rat liver, and by Hevea brasiliensis latex. 2. In agreement with previous reports the incorporation of acetyl-CoA into isoprenoids was not inhibited by avidin and was not stimulated by HCO(3) (-). In a cell-free yeast preparation addition of HCO(3) (-) stimulated the formation of fatty acids from acetyl-CoA and decreased the incorporation into unsaponifiable lipids. 3. The labelling patterns of beta-hydroxy-beta-methylglutaryl-CoA formed from [2-(14)C]- and [1,3-(14)C]-malonyl-CoA in rat and pigeon liver preparations were those that would be expected if malonyl-CoA underwent decarboxylation to acetyl-CoA before incorporation. 4. The labelling pattern of ergosterol formed by cell-free yeast preparations from [2-(14)C]malonyl-CoA was also consistent with decarboxylation of malonyl-CoA before incorporation. 5. The incorporation of [2-(14)C]malonyl-CoA into mevalonate by rat liver preparations was related to the malonyl-CoA decarboxylase activity present in the preparation.
D000105:Acetyl Coenzyme A; D000818:Animals; D001639:Bicarbonates / Q000494:pharmacology; D002247:Carbon Isotopes; D002262:Carboxy-Lyases / Q000378:metabolism; D002474:Cell-Free System; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D002854:Chromatography, Paper; D003065:Coenzyme A / Q000378:metabolism*; D010856:Columbidae; D004875:Ergosterol / Q000096:biosynthesis; D005977:Glutarates / Q000096:biosynthesis*; D008055:Lipids / Q000096:biosynthesis; D008099:Liver / Q000378:metabolism; D008314:Malonates / Q000378:metabolism*; D008798:Mevalonic Acid / Q000096:biosynthesis; D010944:Plants / Q000378:metabolism; D051381:Rats; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013729:Terpenes / Q000096:biosynthesis*; D013997:Time Factors
D001639:Bicarbonates; D002247:Carbon Isotopes; D005977:Glutarates; D008055:Lipids; D008314:Malonates; D013729:Terpenes; D000105:Acetyl Coenzyme A; D002262:Carboxy-Lyases; D008798:Mevalonic Acid; D003065:Coenzyme A; D004875:Ergosterol