Purification and partial characterization of linoleoyl-CoA desaturase from rat liver microsomes

Add time:09/09/2019    Source:sciencedirect.com

The terminal enzyme of the linoleoyl-CoA desaturase system was purified from rat liver microsomes by Triton X-100 solubilization, DEAE-cellulose, CM-Sephadex, and affinity chromatography on cytochrome b5-Sepharose. The final enzyme preparation was homogeneous as judged by SDS-polyacrylamide gel electrophoresis and a single polypeptide of 66,000 daltons containing 49% nonpolar amino acid residues. The Δ6-desaturase was found to be a non-heme iron protein containing one atom of iron per one molecule of the enzyme. It was demonstrated that NADH, molecular oxygen, linoleoyl-CoA, lipid or detergent, and three enzymes, NADH-cytochrome b5 reductase [EC 1.6.2.2.], cytochrome b5, and the terminal enzyme, were absolutely essential for Δ6-desaturation. In this reconstituted system the apparent Km values for linoleoyl-CoA and V were 45 μm and 83 nmol/min/mg protein of desaturase, respectively, and the optimal pH was 7.O. The Δ6-desaturase activity in the reconstituted system was inhibited strikingly by iron chelators, cyanide, and p-chloromercuribenzene sulfonate. Furthermore, NADPH-dependent linoleoyl-CoA desaturation could also be reconstituted in the system containing NADPH-cytochrome P-450 reductase [EC 1.6.2.4.], cytochrome b5, Δ6-desaturase, and detergent. However, in this case, the desaturase activity was only 60% that of the NADH-dependent desaturation.

We also recommend Trading Suppliers and Manufacturers of Linoleoyl coenzyme A (cas 13673-87-5). Pls Click Website Link as below: cas 13673-87-5 suppliers

Prev:Effects of fatty acyl-coenzyme A esters on prostaglandin synthesis in rabbit kidney medulla microsomes
Next:Enhanced oral bioavailability of Coenzyme Q10 by self-emulsifying drug delivery systems)