| Autor: |
Catherine Chapus, Laurence Ayvazian, Simone Granon, Brigitte Kerfelec, Isabelle Crenon, Edith Foglizzo, Christophe Dubois |
| Rok vydání: |
2001 |
| Předmět: |
|
| Zdroj: |
Journal of Biological Chemistry. 276:14014-14018 |
| ISSN: |
0021-9258 |
| DOI: |
10.1074/jbc.m010328200 |
| Popis: |
In vertebrates, dietary fat digestion mainly results from the combined effect of pancreatic lipase, colipase, and bile. It has been proposed that in vivo lipase adsorption on oil-water emulsion is mediated by a preformed lipase-colipase-mixed micelle complex. The main lipase-colipase binding site is located on the C-terminal domain of the enzyme. We report here that in vitro the isolated C-terminal domain behaves as a potent noncovalent inhibitor of lipase and that the inhibitory effect is triggered by the presence of micelles. Lipase inhibition results from the formation of a nonproductive C-terminal domain-colipase-micelle ternary complex, which competes for colipase with the active lipase-colipase-micelle ternary complex, thus diverting colipase from its lipase-anchoring function. The formation of such a complex has been evidenced by molecular sieving experiments. This nonproductive complex lowers the amount of active lipase thus reducing lipolysis. Preliminary experiments performed in rats show that the C-terminal domain also behaves as an inhibitor in vivo and thus could be considered a potential new tool for specifically reducing intestinal lipolysis. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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