Magnetic resonance studies of apolipoprotein C-I nitroxide labeled or [13C]methyl enriched at methionine-38.
Magnetic resonance studies of apolipoprotein C-I nitroxide labeled or [13C]methyl enriched at methionine-38.
复制标题
载脂蛋白 C-I 硝基氧标记或 [13C] 甲基在蛋氨酸 38 处富集的磁共振研究。
DOI：
10.1021/bi00563a032
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发表时间：
1980
期刊：
影响因子：
2.9
通讯作者：
Morrisett,JD
中科院分区：
文献类型：
--
作者：
Chen,TC;Knapp,RD;Rohde,MF;Brainard,JR;GottoJr,AM;Sparrow,JT;Morrisett,JD
摘要：人载脂蛋白CI(apoC-I)的三个脂质结合区之一是一个两亲性螺旋，它从33个残基延伸到53个残基，并在第38位包含一个蛋氨酸。甲硫氨酸-38周围的序列参与磷脂结合已经通过连接到硫甲基部分的顺磁性和核报告基团进行了评估。用7V-(2，2，6，6-四甲基哌啶基-1-氧基)溴乙酰胺或富含~(13)CH_3I的~(13)C对该部分进行自旋标记。根据其EPR谱测定，apoC-I的Met-38位氮氧化物的转动关联时间(RC)为0.22 ns。当二肉豆蔻基磷脂酰胆碱(DMPC)与自旋标记的载脂蛋白结合时，RC增加到0.35 ns，表明
Tsung-Chang Chen, Roger D. Knapp, Michael F. Rohde, James R. Brainard, Antonio M. Gotto, Jr., James T. Sparrow, and Joel D. Morrisett* abstract: One of the three proposed lipid-binding regions of the human apolipoprotein CI (apoC-I) is an amphipathic helix which extends from residue 33 to residue 53 and includes a single methionine at sequence position 38. The involvement of the sequence around methionine-38 in phospholipid binding has been evaluated with paramagnetic and nuclear reporter groups attached to the thiomethyl moiety. This moiety has been spin-labeled with 7V-(2, 2, 6, 6-tetramethylpiperidinyl-1-oxy) bromoacetamide or 13C enriched with 13CH3I. As de-termined from its EPR spectrum, the nitroxide at Met-38 of apoC-I had a rotational correlation time (rc) of 0.22 ns. When dimyristoylphosphatidylcholine (DMPC) was bound to the spin-labeled apoprotein, rc increased to 0.35 ns, indicating