Jeffcoat R, Pollard M R
Lipids. 1977 Jun;12(6):480-5. doi: 10.1007/BF02535446.
Unwashed rat liver microsomes were used to study the inhibition of the delta6 and delta9 desaturases by cyclopropenoid fatty acids with the ring structure about the 9,10 or 6,7 carbon atoms. The 9,10 cyclopropenoid acid (sterculic acid) is shown to be an effective inhibitor of only delta9 desaturase and then only in the presence of MgCl2 and coenzyme A (presumably due to the formation of sterculoyl-CoA). Two 6,7 cyclopropenoid acids of different chain lengths showed no marked inhibition of either the delta6 or delta9 desaturase. By the use of [3H]-sterculic acid, it has been shown that under conditions of high inhibition of the delta9 desaturase the inhibitor is not covalently attached to the enzyme at any point. This disproves older ideas on the mechanism of inhibition that assumed reaction between the cyclopropenoid ring and sulphydryl groups on the enzymes.
未洗涤的大鼠肝脏微粒体用于研究具有围绕9,10或6,7碳原子的环结构的环丙烯脂肪酸对δ6和δ9去饱和酶的抑制作用。9,10环丙烯酸（苹婆酸）被证明是仅δ9去饱和酶的有效抑制剂，并且仅在存在MgCl2和辅酶A的情况下（可能是由于形成了苹婆酰辅酶A）。两种不同链长的6,7环丙烯酸对δ6或δ9去饱和酶均未显示出明显的抑制作用。通过使用[3H] - 苹婆酸，已表明在对δ9去饱和酶高度抑制的条件下，抑制剂在任何点都不与酶共价结合。这反驳了关于抑制机制的旧观点，即假设环丙烯环与酶上的巯基之间发生反应。
