Cloning and characterization of unusual @entity844 desaturases from Anemone leveillei: identification of an @entity8595 C20 Delta5-desaturase responsible for the synthesis of XXXX .

@entity844 @entity845 @entity49836 @entity958 @entity1674 @entity1426 @entity1474 @entity9931 @entity8595 @entity1718
The seed oil of Anemone leveillei contains significant amounts of @entity49836 (20:3Delta(5,11,14); SA), an unusual non- @entity845 -interrupted @entity844 with pharmaceutical potential similar to @entity1426 . Two candidate cDNAs (AL10 and AL21) for the C(20) Delta(5cis)-desaturase from developing seeds of A. leveillei were functionally characterized in transgenic @entity958 ( @entity958 ) plants. The open reading frames of both Delta(5)-desaturases showed some similarity to presumptive @entity8595 ( @entity9931 ) desaturases found in animals and plants. When expressed in transgenic @entity958 , AL21 showed a broad range of substrate specificity, utilizing both saturated (16:0 and 18:0) and unsaturated (18:2, n-6 and 18:3, n-3) substrates. In contrast, AL10 did not show any activity in wild-type @entity958 . Coexpression of AL10 or AL21 with a C(18) Delta(9)-elongase in transgenic @entity958 plants resulted in the production of SA and juniperonic @entity844 (20:4Delta(5,11,14,17)). Thus, AL10 acted only on C(20) @entity1474 in a manner analogous to "front-end" desaturases. However, neither AL10 nor AL21 contain the cytochrome b(5) domain normally present in this class of enzymes. @entity8595 profiling of transgenic @entity958 plants and developing A. leveillei seeds revealed significant accumulation of Delta(5)-unsaturated fatty acids as acyl-CoAs compared to the accumulation of these @entity1718 in total lipids. Positional analysis of @entity1674 of A. leveillei seeds showed that Delta(5)-desaturated fatty acids were present in both sn-2 and sn-1 + sn-3 positions, although the majority of 16:1Delta(5), 18:1Delta(5), and SA was present at the sn-2 position. Our data provide biochemical evidence for the A. leveillei Delta(5)-desaturases using @entity8595 substrates.
