Abstract
A method for the fractionation of sheep rumen epithelium with limited mitochondrial breakage is described. The distributions of the enzymes of the 3-hydroxy-3-methylglutaryl-CoA pathway of ketogenesis indicate that this process is exclusively mitochondrial. Enzyme activities are sufficient to account for the ketogenic rates found in vivo. The failure of (-)-hydroxycitrate to block ketogenic flux supports this view. 3-Hydroxybutyrate dehydrogenase activity is largely associated with particulate material in the mitochondrial fraction. ATP citrate lyase activity was found, with appreciable acetoacetyl-CoA thiolase and 3-hydroxy-3-methylglutaryl-CoA synthase in the cytoplasmic fraction.
Full text
PDFSelected References
These references are in PubMed. This may not be the complete list of references from this article.
- Abdel Rahman S. Comparative study of the urease in the rumen wall and rumen content. Nature. 1966 Feb 5;209(5023):618–619. doi: 10.1038/209618b0. [DOI] [PubMed] [Google Scholar]
- Allred J. B. Properties and subcellular distribution of enzymes required for acetoacetate biosynthesis in chicken liver. Biochim Biophys Acta. 1973 Jan 24;297(1):22–30. doi: 10.1016/0304-4165(73)90045-7. [DOI] [PubMed] [Google Scholar]
- Ash R., Baird G. D. Activation of volatile fatty acids in bovine liver and rumen epithelium. Evidence for control by autoregulation. Biochem J. 1973 Oct;136(2):311–319. doi: 10.1042/bj1360311. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Baird G. D., Hibbitt K. G., Lee J. Enzymes involved in acetoacetate formation in various bovine tissues. Biochem J. 1970 May;117(4):703–709. doi: 10.1042/bj1170703. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brunengraber H., Boutry M., Lowenstein J. M. Fatty acid, 3-beta-hydroxysterol, and ketone synthesis in the perfused rat liver. Effects of (--)-hydroxycitrate and oleate. Eur J Biochem. 1978 Jan 16;82(2):373–384. doi: 10.1111/j.1432-1033.1978.tb12032.x. [DOI] [PubMed] [Google Scholar]
- Chandrasena L. G., Emmanuel B., Hamar D. W., Howard B. R. A comparative study of ketone body metabolism between the camel (Camelus dromedarius) and the sheep (Ovis aries). Comp Biochem Physiol B. 1979;64(1):109–112. doi: 10.1016/0305-0491(79)90192-5. [DOI] [PubMed] [Google Scholar]
- Clinkenbeard K. D., Reed W. D., Mooney R. A., Lane M. D. Intracellular localization of the 3-hydroxy-3-methylglutaryl coenzme A cycle enzymes in liver. Separate cytoplasmic and mitochondrial 3-hydroxy-3-methylglutaryl coenzyme A generating systems for cholesterogenesis and ketogenesis. J Biol Chem. 1975 Apr 25;250(8):3108–3116. [PubMed] [Google Scholar]
- Endemann G., Goetz P. G., Edmond J., Brunengraber H. Lipogenesis from ketone bodies in the isolated perfused rat liver. Evidence for the cytosolic activation of acetoacetate. J Biol Chem. 1982 Apr 10;257(7):3434–3440. [PubMed] [Google Scholar]
- Fenselau A., Wallis K. Comparative studies on 3-oxo acid coenzyme A transferase from various rat tissues. Biochem J. 1974 Sep;142(3):619–627. doi: 10.1042/bj1420619. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Goldfarb S., Pitot H. C. Improved assay of 3-hydroxy-3-methylglutaryl coenzyme A reductase. J Lipid Res. 1971 Jul;12(4):512–515. [PubMed] [Google Scholar]
- Goosen P. C. Metabolism in rumen epithelium oxidation of substrates and formation of ketone bodies by pieces of rumen epithelium. Z Tierphysiol Tierernahr Futtermittelkd. 1976 May;37(1):14–25. doi: 10.1111/j.1439-0396.1976.tb00037.x. [DOI] [PubMed] [Google Scholar]
- Hird F. J., Weidemann M. J. Transport and metabolism of butyrate by isolated rumen epithelium. Biochem J. 1964 Sep;92(3):585–589. doi: 10.1042/bj0920585. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kramer P. R., Miziorko H. M. Purification and characterization of avian liver 3-hydroxy-3-methylglutaryl coenzyme A lyase. J Biol Chem. 1980 Nov 25;255(22):11023–11028. [PubMed] [Google Scholar]
- Leng R. A., West C. E. Contribution of acetate, butyrate, palmitate, stearate and oleate to ketone body synthesis in sheep. Res Vet Sci. 1969 Jan;10(1):57–63. [PubMed] [Google Scholar]
- Longshaw I. D., Bowen N. L., Pogson C. I. The pathway of gluconeogenesis in the cortex of guinea-pig kidney. Use of aminooxyacetate as a transaminase inhibitor. Eur J Biochem. 1972 Feb 15;25(2):366–371. doi: 10.1111/j.1432-1033.1972.tb01705.x. [DOI] [PubMed] [Google Scholar]
- McCowan R. P., Cheng K. J., Bailey C. B., Costerton J. W. Adhesion of bacteria to epithelial cell surfaces within the reticulo-rumen of cattle. Appl Environ Microbiol. 1978 Jan;35(1):149–155. doi: 10.1128/aem.35.1.149-155.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Middleton B. The oxoacyl-coenzyme A thiolases of animal tissues. Biochem J. 1973 Apr;132(4):717–730. doi: 10.1042/bj1320717. [DOI] [PMC free article] [PubMed] [Google Scholar]
- PENNINGTON R. J. The metabolism of short-chain fatty acids in the sheep. I. Fatty acid utilization and ketone body production by rumen epithelium and other tissues. Biochem J. 1952 May;51(2):251–258. doi: 10.1042/bj0510251. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Patel T. B., Clark J. B. Acetoacetate metabolism in rat brain. Development of acetoacetyl-coenzyme A deacylase and 3-hydroxy-3-methylglutaryl-coenzyme A synthase. Biochem J. 1978 Dec 15;176(3):951–958. doi: 10.1042/bj1760951. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SRERE P. A. The citrate cleavage enzyme. I. Distribution and purification. J Biol Chem. 1959 Oct;234:2544–2547. [PubMed] [Google Scholar]
- Smith S. A., Carr F. P., Pogson C. I. The metabolism of L-tryptophan by isolated rat liver cells. Quantification of the relative importance of, and the effect of nutritional status on, the individual pathways of tryptophan metabolism. Biochem J. 1980 Nov 15;192(2):673–686. doi: 10.1042/bj1920673. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith S. A., Elliott K. R., Pogson C. I. Differential effects of tryptophan on glucose synthesis in rats and guinea pigs. Biochem J. 1978 Dec 15;176(3):817–825. doi: 10.1042/bj1760817. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith S. A., Pogson C. I. The metabolism of L-tryptophan by isolated rat liver cells. Effect of albumin binding and amino acid competition on oxidatin of tryptophan by tryptophan 2,3-dioxygenase. Biochem J. 1980 Mar 15;186(3):977–986. doi: 10.1042/bj1860977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stegink L. D., Coon M. J. Stereospecificity and other properties of highly purified beta-hydroxy-beta-methylglutaryl coenzyme A cleavage enzyme from bovine liver. J Biol Chem. 1968 Oct 25;243(20):5272–5279. [PubMed] [Google Scholar]
- Tisdale M. J., Brennan R. A. Loss of acetoacetate coenzyme A transferase activity in tumours of peripheral tissues. Br J Cancer. 1983 Feb;47(2):293–297. doi: 10.1038/bjc.1983.38. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Watson H. R., Lindsay D. B. 3-hydroxybutyrate dehydrogenase in tissues from normal and ketonaemic sheep. Biochem J. 1972 Jun;128(1):53–57. doi: 10.1042/bj1280053. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Watson J. A., Fang M., Lowenstein J. M. Tricarballylate and hydroxycitrate: substrate and inhibitor of ATP: citrate oxaloacetate lyase. Arch Biochem Biophys. 1969 Dec;135(1):209–217. doi: 10.1016/0003-9861(69)90532-3. [DOI] [PubMed] [Google Scholar]
- Weekes T. E. The preparation of a viable suspension of epithelial cells from the rumen mucosa of cattle. Comp Biochem Physiol B. 1974 Nov 15;49(3):407–413. doi: 10.1016/0305-0491(74)90177-1. [DOI] [PubMed] [Google Scholar]
- Williamson D. H., Bates M. W., Krebs H. A. Activity and intracellular distribution of enzymes of ketone-body metabolism in rat liver. Biochem J. 1968 Jul;108(3):353–361. doi: 10.1042/bj1080353. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Young J. W., Thorp S. L., De Lumen H. Z. Activity of selected gluconeogenic and lipogenic enzymes in bovine rumen mucosa, liver and adipose tissue. Biochem J. 1969 Aug;114(1):83–88. doi: 10.1042/bj1140083. [DOI] [PMC free article] [PubMed] [Google Scholar]