Origin and behavior of deuteron spin echoes in selectively labeled amino acids, myoglobin microcrystals, and purple membranes.
Origin and behavior of deuteron spin echoes in selectively labeled amino acids, myoglobin microcrystals, and purple membranes.
复制标题
氘核自旋的起源和行为在选择性标记的氨基酸、肌红蛋白微晶和紫色膜中回响。
DOI：
10.1021/bi00308a039
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发表时间：
1984
期刊：
影响因子：
2.9
通讯作者：
Oldfield,E
中科院分区：
文献类型：
--
作者：
Baianu,IC;Gutowsky,HS;Oldfield,E
离子C. Baianu, 1 H. S. Gutowsky，和EricOldfield*摘要：我们获得了来自鲸（Physeter catodon）的结晶-[-2 6]缬氨酸，[s -甲基- 2h} -蛋氨酸，含蛋氨酸-55和蛋氨酸-131上的氘甲基，和[-y- 2h6]缬氨酸标记的细菌-紫红质的氘核磁共振自旋回波光谱。通过使用90—ك90 （XY）和90—/30·（XX）脉冲序列，并观察自旋回波振幅与脉冲间隔的关系，我们确定了在这些典型的选择性氘化凝聚相生物系统中获得的所谓“四极回波”实际上是由质子-氘核和氘核-氘核偶极相互作用强烈调制的。这两种氨基酸和蛋白质晶体表现为典型的有机固体，在过去的十多年里，人们对使用氘（2H）核磁共振（NMR） 1作为探测细胞膜静态和动态结构的工具产生了相当大的兴趣（Oldfield et al., 1972, 1981; Mantsch et al., 1977, Seelig, 1977）。早期的研究受到许多因素的阻碍，主要是使用低场核磁共振仪器。因此，连续波测量的灵敏度非常低，而单脉冲后截断的自由感应衰减的傅里叶变换由于低场时光谱仪恢复时间长而产生了严重的畸变。Davis等人（1976）克服了后一个问题，他们使用一个共振的双脉冲序列，90-t-9090o，形成所谓的“四极回波”，从而有效地消除了脉冲后接收器过载的问题。
Ion C. Baianu, 1 H. S. Gutowsky, and EricOldfield* abstract: We have obtained deuterium NMR spin-echo spectra of crystalline-[-2 6] valine,[S-methyi-2H}\-methionine, cyanoferrimyoglobin from sperm whale (Physeter catodon), containing deuteriomethyl groups at methionine-55 and methionine-131, and [-y-2H6] valine-labeled bacterio-rhodopsin in the purple membrane of Halobacterium halobium R]. By using 90--ك90 (XY) and 90——/30·(XX) pulse se-quences and observing the dependence of the spin-echo am-plitude upon the interpulse spacingr, we have determined that the so-called “quadrupole echoes” obtained in these typical selectively deuterated condensed-phase biological systems are in fact strongly modulated by proton-deuteron and deuteron-deuteron dipolar interactions. The two amino acids and the protein crystals behaved as typical organic solids, with noFor over 10 years now, there has been considerable interest in the use of deuterium (2H) nuclear magnetic resonance (NMR) 1 as a tool for probing the static and dynamic structures of cell membranes (Oldfield et al., 1972, 1981; Mantsch et al., 1977, Seelig, 1977). Early studies were hampered by a number of factors, the primary one being the use of low-field NMR instrumentation. As a result, continuous-wave mea-surements were of very low sensitivity, whilst the Fourier transforms of truncated free-induction decays following single pulses gave gross distortions, dueto the long spectrometer recovery times at low field. Thislatter problem was overcome by Davis et al.(1976), who used a resonant two-pulse sequence, 90-t-9090o, to form a so-called “quadrupole echo”, thereby effectively eliminating the problem of receiver overload after a pulse.