Huang H S, Chen C J, Lu H S, Chang W C
Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.
FEBS Lett. 1998 Mar 6;424(1-2):22-6. doi: 10.1016/s0014-5793(98)00130-6.
An endogenous lipoxygenase inhibitor, purified from the cytosol of human epidermoid carcinoma A431 cells, was analyzed by N-terminal microsequencing and mass spectrometric analysis. The inhibitor was purified by SDS-PAGE, then subjected to in-gel CNBr cleavage and trypsin digestion. The N-terminal sequence data obtained from a 6-8 kDa band of in-gel CNBr cleavage and the three isolated peptides of in-gel trypsin digestion, and the C-terminal peptide sequence from matrix-assisted laser desorption ionization mass spectrometry matched the sequence of human phospholipid hydroperoxide glutathione peroxidase. The purified inhibitor exhibited peroxidase activity using phosphatidylcholine hydroperoxides as the substrate. We therefore concluded that the lipoxygenase inhibitor present in A431 cells was a phospholipid hydroperoxide glutathione peroxidase.
从人表皮样癌A431细胞的胞质溶胶中纯化得到一种内源性脂氧合酶抑制剂，并通过N端微量测序和质谱分析进行了分析。该抑制剂经SDS-PAGE纯化，然后进行胶内溴化氰裂解和胰蛋白酶消化。从胶内溴化氰裂解的6-8 kDa条带以及胶内胰蛋白酶消化的三个分离肽段获得的N端序列数据，与基质辅助激光解吸电离质谱法得到的C端肽段序列与人磷脂氢过氧化物谷胱甘肽过氧化物酶的序列相匹配。纯化后的抑制剂以磷脂酰胆碱氢过氧化物为底物表现出过氧化物酶活性。因此，我们得出结论，A431细胞中存在的脂氧合酶抑制剂是一种磷脂氢过氧化物谷胱甘肽过氧化物酶。
