Maltese W A, Erdman R A
Weis Center for Research, Geisinger Clinic, Danville, Pennsylvania 17822.
J Biol Chem. 1989 Oct 25;264(30):18168-72.
Mammalian cell proteins, modified post-translationally by derivatives of [3H]mevalonic acid, were subjected to methylation and sulfonium salt cleavage reactions previously used to release isoprenoids from cysteine residues in yeast peptides. The labeled isoprenoid extracted into chloroform comigrated with farnesol through a series of chromatography steps including Sep-Pak C-18 fractionation, size exclusion on Bio-Beads, and reverse-phase chromatography. Further resolution of the material by normal phase liquid chromatography and thin layer chromatography demonstrated the presence of farnesol, nerolidol, and other unidentified hydrophobic derivatives. Similar products were generated when S-farnesyl cysteine was subjected to the methylation and cleavage procedures. These preliminary findings suggest that farnesylation of cysteine residues accounts for the well documented incorporation of mevalonic acid into mammalian cell proteins.
用[3H]甲羟戊酸衍生物进行翻译后修饰的哺乳动物细胞蛋白，进行了甲基化和锍盐裂解反应，这些反应以前用于从酵母肽中的半胱氨酸残基释放类异戊二烯。通过一系列色谱步骤，包括Sep-Pak C-18分级分离、Bio-Beads尺寸排阻和反相色谱，提取到氯仿中的标记类异戊二烯与法呢醇共迁移。通过正相液相色谱和薄层色谱对该物质进行进一步分离，证明存在法呢醇、橙花叔醇和其他未鉴定的疏水衍生物。当S-法呢基半胱氨酸进行甲基化和裂解程序时，会产生类似的产物。这些初步发现表明，半胱氨酸残基的法呢基化解释了甲羟戊酸被充分记录到哺乳动物细胞蛋白中的现象。
