Document type
ArticleVersion
Published versionPublication date
All rights reserved
Please use this identifier to cite or link to this item: https://hdl.handle.net/2445/135597
Pig liver carnitine palmitoyltransferase. Chimera studies show that both the N- and C-terminal regions of the enzyme are important for the unusual high malonyl-CoA sensitivity
Journal Title
Director/Tutor
Journal ISSN
Volume Title
Related resource
Abstract
Pig and rat liver carnitine palmitoyltransferase I (L-CPTI) share common K(m) values for palmitoyl-CoA and carnitine. However, they differ widely in their sensitivity to malonyl-CoA inhibition. Thus, pig l-CPTI has an IC(50) for malonyl-CoA of 141 nm, while that of rat L-CPTI is 2 microm. Using chimeras between rat L-CPTI and pig L-CPTI, we show that the entire C-terminal region behaves as a single domain, which dictates the overall malonyl-CoA sensitivity of this enzyme. The degree of malonyl-CoA sensitivity is determined by the structure adopted by this domain. Using deletion mutation analysis, we show that malonyl-CoA sensitivity also depends on the interaction of this single domain with the first 18 N-terminal amino acid residues. We conclude that pig and rat L-CPTI have different malonyl-CoA sensitivity, because the first 18 N-terminal amino acid residues interact differently with the C-terminal domain. This is the first study that describes how interactions between the C- and N-terminal regions can determine the malonyl-CoA sensitivity of L-CPTI enzymes using active C-terminal chimeras.
Subject (English)
Citation
Citation
NICOT, Carine, et al. Pig liver carnitine palmitoyltransferase. Chimera studies show that both the N- and C-terminal regions of the enzyme are important for the unusual high malonyl-CoA sensitivity. Journal of Biological Chemistry. 2002. Vol. 277, num. 12, pags. 10044-10049. ISSN 0021-9258. [consulted: 9 of June of 2026]. Available at: https://hdl.handle.net/2445/135597