Publication Date
7-1-2023
Journal
Journal of Biological Chemistry
Abstract
Mammalian stearoyl-CoA desaturase-1 (SCD1) introduces a double-bond to a saturated long-chain fatty acid in a reaction catalyzed by a diiron center. The diiron center is well-coordinated by conserved histidine residues and is thought to remain with the enzyme. However, we find here that SCD1 progressively loses its activity during catalysis and becomes fully inactive after about nine turnovers. Further studies show that the inactivation of SCD1 is due to the loss of an iron (Fe) ion in the diiron center and that the addition of free ferrous ions (Fe
Keywords
diiron; electron paramagnetic resonance (EPR); labile iron; lipid desaturation; metalloenzyme; stearoyl-CoA desaturase (SCD)