Conformational Studies on the Δ<sup>8</sup>(<i>E</i>,<i>Z</i>)-Sphingolipid Desaturase from <i>Helianthus annuus</i> with Chiral Fluoropalmitic Acids As Mechanistic Probes
The Δ8-sphingolipid desaturase from sunflower (Helianthus annuus) converts phytosphinganine into a mixture of Δ8-(E)- and -(Z)-phytosphingenines by removal of two syn-hydrogen atoms from anti-, and gauche-conformations of the substrate. With chiral (R)-6-, (S)-6-, (R)-7-, and (S)-7-fluoropalmitic acids the importance of conformations for the formation of (E)- and (Z)-isomers was investigated by using