Abstract
The generation of 13C-labelled lactate by colon carcinoma cells of the Caco-2 line incubated for 120 min in the presence of [2-13C]propionate (10 mM) was assessed by 13C NMR. About 10% of the total amount of 13C-labelled lactate was recovered in the cell pellet and displayed a [2-13C]lactate/[3-13C]lactate isotopomer ratio of 1.18 +/- 0.01. An even higher isotopomer ratio of 1.53 +/- 0.14 was observed in the case of 13C-labelled lactate released by the cells into the incubation medium. These findings indicate that, in the Caco-2 cells, metabolic intermediates of the Krebs cycle undergo enzyme-to-enzyme channelling in the sequence of reactions catalysed by succinyl-CoA synthetase, succinate dehydrogenase and fumarase.
Full Text
The Full Text of this article is available as a PDF (263.7 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Fogh J., Wright W. C., Loveless J. D. Absence of HeLa cell contamination in 169 cell lines derived from human tumors. J Natl Cancer Inst. 1977 Feb;58(2):209–214. doi: 10.1093/jnci/58.2.209. [DOI] [PubMed] [Google Scholar]
- Hidalgo I. J., Raub T. J., Borchardt R. T. Characterization of the human colon carcinoma cell line (Caco-2) as a model system for intestinal epithelial permeability. Gastroenterology. 1989 Mar;96(3):736–749. [PubMed] [Google Scholar]
- Malaisse W. J., Maggetto C., Leclercq-Meyer V., Sener A. Interference of glycogenolysis with glycolysis in pancreatic islets from glucose-infused rats. J Clin Invest. 1993 Feb;91(2):432–436. doi: 10.1172/JCI116219. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Malaisse W. J., Marynissen G., Sener A. Possible role of glycogen accumulation in B-cell glucotoxicity. Metabolism. 1992 Aug;41(8):814–819. doi: 10.1016/0026-0495(92)90160-c. [DOI] [PubMed] [Google Scholar]
- Pronk J. T., van der Linden-Beuman A., Verduyn C., Scheffers W. A., van Dijken J. P. Propionate metabolism in Saccharomyces cerevisiae: implications for the metabolon hypothesis. Microbiology. 1994 Apr;140(Pt 4):717–722. doi: 10.1099/00221287-140-4-717. [DOI] [PubMed] [Google Scholar]
- Scheppach W. Effects of short chain fatty acids on gut morphology and function. Gut. 1994 Jan;35(1 Suppl):S35–S38. doi: 10.1136/gut.35.1_suppl.s35. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sherry A. D., Sumegi B., Miller B., Cottam G. L., Gavva S., Jones J. G., Malloy C. R. Orientation-conserved transfer of symmetric Krebs cycle intermediates in mammalian tissue. Biochemistry. 1994 May 24;33(20):6268–6275. doi: 10.1021/bi00186a029. [DOI] [PubMed] [Google Scholar]
- Sumegi B., Podanyi B., Forgo P., Kover K. E. Metabolism of [3-13C]pyruvate and [3-13C]propionate in normal and ischaemic rat heart in vivo: 1H- and 13C-NMR studies. Biochem J. 1995 Nov 15;312(Pt 1):75–81. doi: 10.1042/bj3120075. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sumegi B., Sherry A. D., Malloy C. R. Channeling of TCA cycle intermediates in cultured Saccharomyces cerevisiae. Biochemistry. 1990 Oct 2;29(39):9106–9110. doi: 10.1021/bi00491a002. [DOI] [PubMed] [Google Scholar]
- Zhang T. M., Jijakli H., Malaisse W. J. Nutritional efficiency of succinic acid and glutamic acid dimethyl esters in colon carcinoma cells. Am J Physiol. 1996 May;270(5 Pt 1):G852–G859. doi: 10.1152/ajpgi.1996.270.5.G852. [DOI] [PubMed] [Google Scholar]