Selective Inhibition of Cholesterol Synthesis by Cell-free Preparations of Rat Liver by Using Inhibitors of Cytoplasmic Acetoacetyl-coenzyme A Thiolase

Overview

Journal Biochem J

Specialty Biochemistry

Date 1975 Jun 1

PMID 241330

Citations 2

Authors

D P Bloxham

Affiliations

Soon will be listed here.

Abstract

Cytoplasmic acetoacetyl-CoA thiolase (acetyl-CoA C-acetyltransferase, EC 2.3.1.9) was partially purified from rat liver. The enzyme was irreversibly inactivated by 4-bromocrotonyl-CoA, but-3-ynoyl-CoA, pent-3-ynoyl-CoA and dec-3-ynoyl-CoA. In the case of the alk-3-ynoyl-CoA esters the potency as alkylating agents of acetoacetyl-CoA thiolase decreased with increased chain length of the alk-3-ynoyl moiety. Advantage was taken of the specific action of alk-3-ynoyl-CoA esters on acetoacetyl-CoA thiolase to show that in a postmitochondrial fraction from rat liver they are effective inhibitors of cholesterol synthesis from sodium [2-14C]acetate under conditions when mevalonate conversion into cholesterol and fatty acid synthesis are unafffected. Short-chain alk-3-ynoic acids have little effect on sterol synthesis, although dec-3-ynoic acid is an effective inhibitor owing to its conversion into the CoA ester by the microsomal fatty acyl-CoA synthetase.

Citing Articles

Effect of methyl 2-hexadecynoate on hepatic fatty acid metabolism.

Wood R, Lee T, Gershon H Lipids. 1980; 15(3):141-50.

PMID: 7374364 DOI: 10.1007/BF02540960.

Synthesis of chloromethyl ketone derivatives of fatty acids. Their use as specific inhibitors of acetoacetyl-coenzyme A thiolase, cholesterol biosynthesis and fatty acid synthesis.

Bloxham D, Chalkley R, Coghlin S, Salam W Biochem J. 1978; 175(3):999-1011.

PMID: 33667 PMC: 1186163. DOI: 10.1042/bj1750999.

References

BUCHER N, Overath P, Lynen F . beta-Hydroxy-beta-methyl-glutaryl coenzyme A reductase, cleavage and condensing enzymes in relation to cholesterol formation in rat liver. Biochim Biophys Acta. 1960; 40:491-501. DOI: 10.1016/0006-3002(60)91390-1. View

Akhtar M, Rahimtula A, Watkinson I, Wilton D, MUNDAY K . The status of C-6, C-7, C-15 and C-16 hydrogen atoms in cholesterol biosynthesis. Eur J Biochem. 1969; 9(1):107-11. DOI: 10.1111/j.1432-1033.1969.tb00582.x. View

BRODIE J, Wasson G, Porter J . The participation of malonyl coenzyme A in the biosynthesis of mevalonic acid. J Biol Chem. 1963; 238:1294-301. View

HERNDON Jr J, SIPERSTEIN M . Desmosterol deposition in human and experimental atherosclerosis. Circ Res. 1963; 12:228-34. DOI: 10.1161/01.res.12.2.228. View

Ellman G . Tissue sulfhydryl groups. Arch Biochem Biophys. 1959; 82(1):70-7. DOI: 10.1016/0003-9861(59)90090-6. View

Lynen F . Functional group of coenzyme A and its metabolic relations, especially in the fatty acid cycle. Fed Proc. 1953; 12(3):683-91. View

Kornberg A, PRICER Jr W . Enzymatic synthesis of the coenzyme A derivatives of long chain fatty acids. J Biol Chem. 1953; 204(1):329-43. View

Holland P, Sherratt H . Biochemical effects of the hypoglycaemic compound pent-4-enoic acid and related non-hypoglycaemic fatty acids. Effects of the free acids and their carnitine esters on coenzyme A-dependent oxidations in rat liver mitochondria. Biochem J. 1973; 136(1):157-71. PMC: 1165935. DOI: 10.1042/bj1360157. View

Morisaki M, Bloch K . On the mode of interaction of -hydroxydecanoyl thioester dehydrase with allenic acid derivatives. Biochemistry. 1972; 11(3):309-14. DOI: 10.1021/bi00753a001. View

10.

DEMPSEY M . Regulation of steroid biosynthesis. Annu Rev Biochem. 1974; 43(0):967-90. DOI: 10.1146/annurev.bi.43.070174.004535. View

11.

Middleton B . The kinetic mechanism and properties of the cytoplasmic acetoacetyl-coenzyme A thiolase from rat liver. Biochem J. 1974; 139(1):109-21. PMC: 1166257. DOI: 10.1042/bj1390109. View

12.

Middleton B, Tubbs P . An enzyme-bound intermediate in the biosynthesis of 3-hydroxy-3-methylglutaryl-coenzyme A. Biochem J. 1974; 137(1):15-23. PMC: 1166075. DOI: 10.1042/bj1370015. View

13.

Clinkenbeard K, Sugiyama T, Moss J, REED W, Lane M . Molecular and catalytic properties of cytosolic acetoacetyl coenzyme A thiolase from avian liver. J Biol Chem. 1973; 248(7):2275-84. View

14.

Bloxham D, Wilton D, Akhtar M . Studies on the mechanism and regulation of C-4 demethylation in cholesterol biosynthesis. The role of adenosine 3':5'-cyclic monophosphate. Biochem J. 1971; 125(2):625-34. PMC: 1178100. DOI: 10.1042/bj1250625. View

15.

FIMOGNARI G, Rodwell V . Mevalonate biosynthesis in rat liver. Lipids. 1970; 5(1):104-8. DOI: 10.1007/BF02531103. View

16.

Bloxham D, Akhtar M . Studies on the control of cholesterol biosynthesis: the adenosine 3':5'-cyclic monophosphate-dependent accumulation of a steroid carboxylic acid. Biochem J. 1971; 123(2):275-8. PMC: 1176933. DOI: 10.1042/bj1230275. View

17.

Higgins M, KEKWICK R . An investigation into the role of malonyl-coenzyme A in isoprenoid biosynthesis. Biochem J. 1973; 134(1):295-310. PMC: 1177809. DOI: 10.1042/bj1340295. View

18.

Holland P, Senior A, Sherratt H . Biochemical effects of the hypoglycaemic compound pent-4-enoic acid and related non-hypoglycaemic fatty acids. Effects of their coenzyme A esters on enzymes of fatty acid oxidation. Biochem J. 1973; 136(1):173-84. PMC: 1165936. DOI: 10.1042/bj1360173. View

19.

Holland P, Clark M, Bloxham D . Inactivation of pig heart thiolase by 3-butynoyl coenzyme A, 3-pentynoyl coenzyme A, and 4-bromocrotonyl coenzyme A. Biochemistry. 1973; 12(17):3309-15. DOI: 10.1021/bi00741a024. View

20.

Gehring U, RIEPERTINGER C, Lynen F . [Purification and crystallization of thiolase; study of its action mechanism]. Eur J Biochem. 1968; 6(2):264-80. DOI: 10.1111/j.1432-1033.1968.tb00446.x. View