Investigation of the interaction between thallous ions and gramicidin A in dimyristoylphosphatidylcholine vesicles: a thallium-205 NMR equilibrium study.
Investigation of the interaction between thallous ions and gramicidin A in dimyristoylphosphatidylcholine vesicles: a thallium-205 NMR equilibrium study.
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二肉豆蔻酰磷脂酰胆碱囊泡中亚铊离子和短杆菌肽 A 之间相互作用的研究：铊 205 NMR 平衡研究。
DOI：
10.1021/bi00368a040
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发表时间：
1986
期刊：
影响因子：
2.9
通讯作者：
Millett,FS
中科院分区：
文献类型：
--
作者：
Shungu,DC;Hinton,JF;Koeppe2nd,RE;Millett,FS
阿肯色大学化学与生物化学系，费耶特维尔，阿肯色州 72701 收稿日期：1986 年 3 月 18 日；修订稿于 1986 年 6 月 6 日收到摘要：本研究首次直接观察到 Tl+ 离子对短杆菌肽 A 通道的多重占据。 205T1 NMR 已用于研究掺入超声处理的二肉豆蔻酰磷脂酰胆碱囊泡中的短杆菌肽 A 与 T1+ 的平衡结合。结果表明，只有多通道占用才能解释所测量的 205T1 化学位移。对数据进行分析，得出在 34°C 下第一和第二个离子的结合的平衡缔合常数分别为 450-600 和 5-20 M"1。（jramicidin A，一种从短芽孢杆菌中分离出来的线性十五肽抗生素，具有众所周知的氨基酸序列（Sarges & Witkop，1965）。在天然和人造脂质膜中，它二聚形成离子传输跨膜通道（Hladky & Haydon, 1970, 1972; Bamberg & Lauger, 1973; Urry, 1971; Veatch & Stryer, 1977; Krasne et al., 1971）。
Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701 Received March 18, 1986; Revised Manuscript Received June 6, 1986 abstract: This study reports the first direct observation of multiple occupancy of the gramicidin A channel by Tl+ ions. 205T1 NMR has been used tostudy the equilibrium binding of Tl+ by gramicidin A incorporated in sonicated dimyristoylphosphatidylcholine vesicles. It is shown that only multiple-channel occupancy can account for the 205T1 chemical shifts measured. The data are analyzed to yield the equilibrium association constants of 450-600 and 5-20 M" 1 for the bindingof the first and the second ions at 34 C, respectively.(jramicidin A, a linear pentadecapeptide antibiotic isolated from Bacillus brevis, has a well-known amino acidsequence (Sarges & Witkop, 1965). In natural and artificial lipid membranes, it dimerizes to form ion-transporting transmembrane channels (Hladky & Haydon, 1970, 1972; Bamberg & Lauger, 1973; Urry, 1971; Veatch & Stryer, 1977; Krasne et al., 1971). The channels exhibit a number of properties that