Acyl-CoA elongase from a higher plant (Lunaria annua): metabolic intermediates of very-long-chain acyl-CoA products and substrate specificity.
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.
Fehling
E
E
Federal Center for Lipid Research, H.P. Kaufmann-Institut, Müster, Germany.
Mukherjee
K D
KD
D051080:Acyl-Carrier Protein S-Malonyltransferase; D000217:Acyltransferases / Q000378:metabolism*; D002855:Chromatography, Thin Layer; D010944:Plants / Q000201:enzymology*; D013379:Substrate Specificity
D000217:Acyltransferases; D051080:Acyl-Carrier Protein S-Malonyltransferase