Regulation of the biosynthesis of 4,7,10,13,16-docosapentaenoic acid
| dc.contributor.author | Mohammed, B. S. | |
| dc.contributor.author | Luthria, D. L. | |
| dc.contributor.author | Baykousheva, S. P. | |
| dc.contributor.author | Sprecher, H. | |
| dc.date.accessioned | 2011-06-29T21:15:23Z | |
| dc.date.available | 2011-06-29T21:15:23Z | |
| dc.date.issued | 1997 | |
| dc.description.abstract | It is now established that fatty acid 7,10,13,16-22:4 is metabolized into 4,7,10,13,16-22:5 as follows: 7,10,13,16-22:4-->9,12,15, 18-24:4-->6,9,12,15,18-24:5-->4,7,10,13,16-22:5. Neither C24 fatty acid was esterified to 1-acyl-sn-glycero-3-phosphocholine (1-acyl-GPC) by microsomes, whereas the rates of esterification of 4, 7,10,13,16-22:5, 7,10,13,16-22:4 and 5,8,11,14-20:4 were respectively 135, 18 and 160 nmol/min per mg of microsomal protein. About four times as much acid-soluble radioactivity was produced when peroxisomes were incubated with [3-14C]9,12,15,18-24:4 compared with 6,9,12,15,18-24:5. Only [1-14C]7,10,13,16-22:4 accumulated when [3-14C]9,12,15,18-24:4 was the substrate, but both 4,7,10,13,16-22:5 and 2-trans-4,7,10,13,16-22:6 were produced from [3-14C]6,9,12,15, 18-24:5. When the two C24 fatty acids were incubated with peroxisomes, microsomes and 1-acyl-GPC there was a decrease in the production of acid-soluble radioactivity from [3-14C]6,9,12,15, 18-24:5, but not from [3-14C]9,12,15,18-24:4. The preferential fate of [1-14C]4,7,10,13,16-22:5, when it was produced, was to move out of peroxisomes for esterification into the acceptor, whereas only small amounts of 7,10,13,16-22:4 were esterified. By using 2H-labelled 9,12,15,18-24:4 it was shown that, when 7,10,13,16-22:4 was produced, its primary metabolic fate was degradation to yield esterified arachidonate. Collectively, the results show that an inverse relationship exists between rates of peroxisomal beta-oxidation and of esterification into 1-acyl-GPC by microsomes. Most importantly, when a fatty acid is produced with its first double bond at position 4, it preferentially moves out of peroxisomes for esterification to 1-acyl-GPC by microsomes, rather than being degraded further via a cycle of beta-oxidation that requires NADPH-dependent 2,4-dienoyl-CoA reductase. | en_US |
| dc.identifier.citation | Mohammed, B. S., D. L. Luthria, S. P. Bakousheva, and H. Sprecher. 1997. Regulation of the biosynthesis of 4,7,10,13,16-docosapentaenoic acid. Biochemical Journal 326:425-430 | en_US |
| dc.identifier.uri | http://hdl.handle.net/1903/11410 | |
| dc.language.iso | en_US | en_US |
| dc.relation.isAvailableAt | Digital Repository at the University of Maryland | en_us |
| dc.relation.isAvailableAt | University of Maryland Libraries | en_us |
| dc.relation.isAvailableAt | University of Maryland (College Park, MD) | en_us |
| dc.subject | Acylation | en_US |
| dc.subject | Esterification | en_US |
| dc.subject | Fatty Acids | en_US |
| dc.subject | metabolism | en_US |
| dc.subject | Fatty Acids, Unsaturated/biosynthesis | en_US |
| dc.subject | Fatty Acids, Unsaturated/metabolism | en_US |
| dc.subject | Microsomes, Liver/metabolism | en_US |
| dc.subject | Oxidation-Reduction | en_US |
| dc.subject | Phosphorylcholine/metabolism | en_US |
| dc.subject | Rats | en_US |
| dc.title | Regulation of the biosynthesis of 4,7,10,13,16-docosapentaenoic acid | en_US |
| dc.type | Article | en_US |