EC number 3.4.24.81 BRENDA BRENDA entry KEGG KEGG entry | IntEnz IntEnz view ExPASy NiceZyme view MetaCyc | |
Dihydroceramide desaturase is the enzyme involved in the conversion of dihydroceramide into ceramide by inserting the 4,5-trans-double bond to the sphingolipid backbone of dihydroceramide. DDase require the O2 and the NAD(P)H as cofactor.
The activity of DDase is influenced by several factors as 1.alkyl chain length of the sphingoid base (in the order C18 > C12 > C8) and fatty acid (C8 > C18)2. The stereochemistry of the sphingoid base (D-erythro- > L-threo-dihydroceramides)3.the nature of the headgroup, with the highest activity with dihydroceramide, but some (approximately 20%) activity with dihydroglucosylceramide 4. The ability to utilize alternative reductants like ascorbic acid could substitute for a reduced pyridine nucleotide, but it act as inhibitory at higher concentrations.
N-[(1R,2S)-2-hydroxy-1-hydroxymethyl-2-(2-tridecyl-1-cyclopropenyl)ethyl]octanamide (GT11), is the inhibitor DDase activity.