Oxidative desaturation of eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid: comparison of different diets on oxidative desaturation at the 5,6 and 6,7 positions
The oxidative desaturation of [1-14C]eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid by rat liver microsomes was studied, and the kinetic conditions appropriate to measure the specific activity of the enzyme were determined. A comparative study of the effects of a balanced diet and essential...
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| Format: | Article |
| Language: | English |
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Elsevier
1972-11-01
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| Series: | Journal of Lipid Research |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S0022227520393494 |
| _version_ | 1818459774713331712 |
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| author | Juan C. Castuma Angel Catala Rodolfo R. Brenner |
| author_facet | Juan C. Castuma Angel Catala Rodolfo R. Brenner |
| author_sort | Juan C. Castuma |
| collection | DOAJ |
| description | The oxidative desaturation of [1-14C]eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid by rat liver microsomes was studied, and the kinetic conditions appropriate to measure the specific activity of the enzyme were determined. A comparative study of the effects of a balanced diet and essential fatty acid-free diets on the oxidative desaturation of oleic and linoleic acids at the 6,7 position and the oxidative desaturation of eicosadienoic acid at the 5,6 position were made. Eicosadienoic acid showed a higher conversion than oleic acid for all the diets. The conversion of oleic and linoleic acids to Δ6 acids was equally increased by fat-free diets with or without added methyl palmitate, whereas the oxidative 5-desaturation of eicosadienoic acid at the 5,6 position was not changed. The effect was apparently independent of the amount of endogenous free fatty acids. The results suggest that the rate-limiting and principal regulatory step in the biosynthesis of eicosa-5,8,11-trienoic acid is the 6-desaturation of oleic acid. The 5-desaturation of eicosadienoic acid was increased by a protein diet and decreased by alloxan diabetes to a lesser extent than the 6-desaturation of linoleic acid. The 5-desaturation of eicosadienoic acid would constitute a secondary regulatory step. |
| first_indexed | 2024-12-14T23:19:42Z |
| format | Article |
| id | doaj.art-8ff61559ad304ec1bee94caed466fdb2 |
| institution | Directory Open Access Journal |
| issn | 0022-2275 |
| language | English |
| last_indexed | 2024-12-14T23:19:42Z |
| publishDate | 1972-11-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Lipid Research |
| spelling | doaj.art-8ff61559ad304ec1bee94caed466fdb22022-12-21T22:44:00ZengElsevierJournal of Lipid Research0022-22751972-11-01136783789Oxidative desaturation of eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid: comparison of different diets on oxidative desaturation at the 5,6 and 6,7 positionsJuan C. Castuma0Angel Catala1Rodolfo R. Brenner2Cátedra de Bioquímica, Instituto de Fisiología, Facultad de Ciencias Médicas, U.N.L.P., Calle 60 y 120, La Plata, ArgentinaCátedra de Bioquímica, Instituto de Fisiología, Facultad de Ciencias Médicas, U.N.L.P., Calle 60 y 120, La Plata, ArgentinaCátedra de Bioquímica, Instituto de Fisiología, Facultad de Ciencias Médicas, U.N.L.P., Calle 60 y 120, La Plata, ArgentinaThe oxidative desaturation of [1-14C]eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid by rat liver microsomes was studied, and the kinetic conditions appropriate to measure the specific activity of the enzyme were determined. A comparative study of the effects of a balanced diet and essential fatty acid-free diets on the oxidative desaturation of oleic and linoleic acids at the 6,7 position and the oxidative desaturation of eicosadienoic acid at the 5,6 position were made. Eicosadienoic acid showed a higher conversion than oleic acid for all the diets. The conversion of oleic and linoleic acids to Δ6 acids was equally increased by fat-free diets with or without added methyl palmitate, whereas the oxidative 5-desaturation of eicosadienoic acid at the 5,6 position was not changed. The effect was apparently independent of the amount of endogenous free fatty acids. The results suggest that the rate-limiting and principal regulatory step in the biosynthesis of eicosa-5,8,11-trienoic acid is the 6-desaturation of oleic acid. The 5-desaturation of eicosadienoic acid was increased by a protein diet and decreased by alloxan diabetes to a lesser extent than the 6-desaturation of linoleic acid. The 5-desaturation of eicosadienoic acid would constitute a secondary regulatory step.http://www.sciencedirect.com/science/article/pii/S0022227520393494microsomesfatty acid synthesislinoleic acidoleic acidessential fatty acid-deficient dietprotein diet |
| spellingShingle | Juan C. Castuma Angel Catala Rodolfo R. Brenner Oxidative desaturation of eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid: comparison of different diets on oxidative desaturation at the 5,6 and 6,7 positions Journal of Lipid Research microsomes fatty acid synthesis linoleic acid oleic acid essential fatty acid-deficient diet protein diet |
| title | Oxidative desaturation of eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid: comparison of different diets on oxidative desaturation at the 5,6 and 6,7 positions |
| title_full | Oxidative desaturation of eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid: comparison of different diets on oxidative desaturation at the 5,6 and 6,7 positions |
| title_fullStr | Oxidative desaturation of eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid: comparison of different diets on oxidative desaturation at the 5,6 and 6,7 positions |
| title_full_unstemmed | Oxidative desaturation of eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid: comparison of different diets on oxidative desaturation at the 5,6 and 6,7 positions |
| title_short | Oxidative desaturation of eicosa-8,11-dienoic acid to eicosa-5,8,11-trienoic acid: comparison of different diets on oxidative desaturation at the 5,6 and 6,7 positions |
| title_sort | oxidative desaturation of eicosa 8 11 dienoic acid to eicosa 5 8 11 trienoic acid comparison of different diets on oxidative desaturation at the 5 6 and 6 7 positions |
| topic | microsomes fatty acid synthesis linoleic acid oleic acid essential fatty acid-deficient diet protein diet |
| url | http://www.sciencedirect.com/science/article/pii/S0022227520393494 |
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