Furuyoshi S, Shi Y Q, Rando R R
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115.
Biochemistry. 1993 May 25;32(20):5425-30. doi: 10.1021/bi00071a018.
The wax ester n-dodecyl palmitate is shown to be synthesized by retinal pigment epithelial membranes. The biosynthesis of this ester is phospholipid dependent and occurs via the transfer of a palmitoyl group from the sn-1 position of lecithin to n-dodecanol. When retinal pigment epithelial membranes are used as the source of enzyme, the apparent Michaelis constant for n-dodecanol in this process is 65.8 microM, and the maximal velocity for n-dodecyl palmitate synthesis is 16.2 nmol/(h.mg of protein). The enzymatic activity is membrane associated and shows a maximum velocity between pH8 and pH9. This transesterification process appears to be similar to the lecithin retinol acyl transferase reaction and is a further example of acyl group transfer reactions from the sn-1 position of phospholipids.
蜡酯棕榈酸正十二酯被证明是由视网膜色素上皮膜合成的。这种酯的生物合成依赖于磷脂，并且是通过将棕榈酰基从卵磷脂的sn-1位转移到正十二醇上而发生的。当使用视网膜色素上皮膜作为酶源时，此过程中正十二醇的表观米氏常数为65.8微摩尔，棕榈酸正十二酯合成的最大速度为16.2纳摩尔/（每小时·毫克蛋白质）。酶活性与膜相关，在pH8至pH9之间显示出最大速度。这种酯交换过程似乎类似于卵磷脂视黄醇酰基转移酶反应，并且是磷脂sn-1位上酰基转移反应的又一个例子。
