Acyl-CoA Elongase From a Higher Plant (Lunaria Annua): Metabolic Intermediates of Very-Long-Chain acyl-CoA Products and Substrate Specificity

Biochim Biophys Acta. 1991 Apr 3;1082(3):239-46. doi: 10.1016/0005-2760(91)90198-q.

Abstract

A particulate fraction (15,000 x g pellet) from developing seeds of honesty (Lunaria annua) was found to synthesize very-long-chain acyl-CoA thioesters in a manner similar to mammalian systems, i.e., via condensation of an acyl-CoA with malonyl-CoA yielding beta-ketoacyl-CoA, which is reduced to beta-hydroxyacyl-CoA, the latter dehydrated to trans-2-enoyl-CoA that is finally reduced to very-long-chain acyl-CoA. Reduced pyridine nucleotides (NADH/NADPH) are required for the reduction steps. In the absence of reduced pyridine nucleotides only the condensation reaction occurs. The acyl-CoA elongase does not exhibit any pronounced specificity for any of the saturated (14:0 to 20:0) or (n - 9)cis-monounsaturated (14:1 to 22:1) acyl-CoA substrates, although both the saturated and monounsaturated acyl-CoA substrates having chain lengths of C18 and C20 are elongated somewhat faster.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyl-Carrier Protein S-Malonyltransferase
  • Acyltransferases / metabolism*
  • Chromatography, Thin Layer
  • Plants / enzymology*
  • Substrate Specificity

Substances

  • Acyltransferases
  • Acyl-Carrier Protein S-Malonyltransferase