Premium
Membrane‐bound phospholipid desaturases
Author(s) -
Pugh E. L.,
Kates M.
Publication year - 1979
Publication title -
lipids
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.601
H-Index - 120
eISSN - 1558-9307
pISSN - 0024-4201
DOI - 10.1007/bf02533867
Subject(s) - lecithin , cytochrome b5 , biochemistry , cytochrome , microsome , phospholipid , chemistry , reductase , yeast , substrate (aquarium) , enzyme , membrane , chromatography , biology , ecology
This review covers studies on membrane‐bound phospholipid desaturases in yeast and rat liver carried out in this laboratory. In yeast the desaturase system was shown to effect the direct desaturation of dioleoyl‐lecithin to dilinoleoyl‐lecithin. In rat liver the desaturase was capable of converting 2‐eicosatrienoyl‐lecithin to 2‐arachidonoyl‐lecithin. Both systems required reduced pyridine nucleotides, O 2 and cytochrome b 5 . Eicosatrienoyl‐lecithin desaturase along with eicosatrienoyl‐CoA desaturase of rat liver microsomes was solubilized with detergents and purified 7–8‐fold from the microsomal pellets. Both activities were reconstituted in the presence of deoxycholate on addition of the other components of the cytochrome b 5 ‐electron transport chain (cytochrome b 5 and NADH‐cytochrome b 5 reductase) to the solubilized desaturase; addition of lecithin further stimulated the activities. The demonstration of desaturation of eicosatrienoyl‐lecithin by a solubilized and partially purified desaturase provides strong evidence for the direct desaturation of the lecithin substrate without prior conversion to the acyl‐CoA thiolester.