Participation of L-ascorbate:ferricytochrome b5 oxidoreductase in ascorbate-dependent fatty acid desaturation of rat liver microsomes.
The microsomal enzyme ascorbate-cytochrome b5 reductase participates in the ascorbate-dependent fatty acid desaturation. Three pieces of evidence are given for this statement: 1) Comparison of the rate of ascorbate-dependent oleate formation with the rate of reduction of cytochrome b5 in microsomes and in the isolated detergent form shows that only the enzymatic reduction of cytochrome b5 is fast enough to support oleate formation; 2) added enriched ascorbate-cytochrome b5 reductase increases the rate of return of stearoyl-CoA oxidised cytochrome b5 back to the reduced state; 3) addition of enriched ascorbate-cytochrome b5 reductase increases the rate of ascorbate-dependent oleate formation in rat liver microsomes.
D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology; D003580:Cytochromes; D004579:Electron Transport; D044943:Fatty Acid Desaturases / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology*; D009243:NAD; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism*; D051381:Rats
D003580:Cytochromes; D005227:Fatty Acids; D009243:NAD; D010088:Oxidoreductases; C019739:L-ascorbate--cytochrome-b5 reductase; D044943:Fatty Acid Desaturases; D001205:Ascorbic Acid