Name: spin saturation transfer difference nmr (sstd nmr): a new tool to obtain kinetic parameters of chemical exchange processes
Uploaded: 2016-11-12T13:00:00.000+00:00
Duration: 11 min 44 s
Description: Watch this Scientific Journal Video about Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes at JoVE.com

Funding by the University of East Anglia, the EPSRC (EP/L012855/1) and the EU (H2020-MSCA-IF-2014-EF-ST-658172) is gratefully acknowledged (MTQ).

注意:使用前请咨询所有相关的材料安全数据表（MSDS）。 1. NMR样品制备<ol><li>称量5毫克的N，N-二甲基乙酰胺，放入适合低温NMR管，并在0.6毫升甲苯-d 8的溶解。 </li></ol> 2. NMR实验装置25 <ol><li> NOE光谱采集<ol><li>执行一维NOE（核极化效应）的实验。26 注:NOE效果可以在任何温度下发生。 一维的NOE谱照射，将在SSTD核磁共振实验被照射信号，被记录在-40℃以确保此处使用的样品中的旋转和磁化传递被最小化，并且因此NOE，如果存在，会占优势，在此实验中进行测量。理想情况下，这两个交换核之间的NOE效应建议立即进行删除ð不存在，以避免与SSTD方法干扰。 </li></ol></li><li> SSTD核磁共振实验设置<ol><li>通过在软件的命令行第一打字EJ插入在磁体样品打开气流。然后，把磁铁顶部的样品，然后键入IJ。等到样品是磁铁内部。 </li><li>一旦样品是在命令行中的磁铁，类型edte。温度变化与第一个选定的温度进行了实验（295.5 K的这种情况下）。让样本稳定在所选择的温度为至少20分钟。 </li><li>执行对样品的一维1 H-NMR实验。 <ol><li>创建的1 H-NMR实验的一个新的数据集。对于此点击文件/新建并命名新的实验。 </li><li> 锁 ， 灵魂 ，topshim，getprosol和RGA:依次等待前面的命令完成输入。 </li><li>键入&lt;EM&gt; ZG收购质子实验。一旦完成型EFP和APK傅里叶变换，并调整阶段。 </li></ol></li><li>创建一个新的数据集，例如，一个1 H NMR实验。对于此点击文件/新建并命名新的实验。 </li><li>在这个新的数据集，在命令行中键入RPAR。选择"STDDIFF"参数集从列表中的一个，例如STDDIFFESGP，然后点击"读取"，然后选择"阅读"（ 图1）。另外， 所有输入RPAR STDDIFFESGP做到这一点。 注:实验可以用此脉冲序列来执行。然而，在我们的实验中使用的脉冲程序是STDDIFF。 </li><li>选择STDDIFF脉冲序列，点击有三个点在PULPROG线（ 图2和3）的按钮。 </li><li>开展SSTD NMR实验前，校准1小时90°硬PULSE（P1）。为了这个目的，确保该样品是在磁铁在所需的温度（步骤2.2.2）。在命令行键入pulsecal并在更高的功率（在这种情况下PL1 = -1分贝）， 即复制90°脉冲的值，所述一个，使该最短脉冲（ 图4）。 </li><li>介绍在实验校准硬脉冲的值。类型getprosol 1H（在步骤2.2.7得到p1的值）（用于PL1值）（ 图5）。 </li><li>设置整形脉冲的长度。 P13型和引进50000微秒（ 图6）的值。 </li><li>设置的选择脉冲形状。要做到这一点，进入电源，然后点击旁边的"编辑..."按钮形状（ 图7）。进入整形脉冲13和选择:GAUS 1.1000（ 图8）。 </li><li>设置的选择脉冲功率（SP13）。它设置为合适的东西， 也就是 </em&gt;，40-60分贝之间在该系统上（对应于大约120赫兹的场强度）（ 图8）。过度的场强会导致不可接受的饱和效应。27-29 注50块是在我们的情况最佳。考虑到，这是一个衰减比例，因此值越小越高射频的功率。因为它对应于饱和高斯级联，施加长时间（几秒），SP13不应去低于40分贝（如果需要的话，请参考仪器的规格，如在高功率长脉冲可能会损坏probehead）。根据我们的经验硬1小时90°脉冲（-1分贝在这项工作）的衰减上述41-61分贝工作正常。尝试总是选择最高的衰减可能导致类似的饱和度。 </li><li> NS型并将其设置为8和类型DS并将其设置为4。 </li></ol></li></ol> 3.核磁共振数据采集的数字处理能力25 <ol><li> SSTD核磁共振实验采集<ol><li>打开步骤2.2.3进行检查，其中，将被照射的信号与1 H NMR实验。为此，在搜索软件浏览器的实验中，右键单击该数据集，然后点击"在新窗口中显示"。 </li><li>移动光标线的信号的中心到照射并写下以ppm化学位移。选择将在实验中使用的光谱宽度。 注意:在这种情况下，这将被照射的信号是在2.17 ppm，且所使用的谱宽为1.46 ppm的。确保没有化学位移改正或者因照射频率可以正确设置。 </li><li>去之前创建的SSTD NMR实验在2.2节中提到的设置。 </li><li>创建与照射的频率的列表。为此，在命令行中键入fq2list并选择现有列表。 </li><li>编辑列表照射频率，包括在3第一行（ 图9）以下的数据: 行1 P（表示后面的数据是用ppm）; 行2 中的信号的频率，以ppm的照射，如在3.1测定。 1;行3.40 ppm的 （即远离化合物的1 H信号，使得在该频率的照射不会影响光谱的频率）。 </li><li>使用新名称保存列表，然后在命令行中键入fq2list并选择刚才创建的列表。 </li><li>居中研究之中，式O1P并选择作为实验，将被照射的信号的化学位移的中心上的信号的实验。 </li><li>类型SW以选择谱宽（1.46 ppm的在这种情况下，但也可以选择任何其它光谱宽度）。 注意:如果改变光谱宽度之后获得的采集时间太长（将介绍在光谱更多的噪声）它CAÑ通过键入AQ以提供所需的自由感应衰减（FID）分辨率（FIDRES，0.25赫兹在这种情况下）进行调整。 </li><li>选择扫描间延迟放宽D1的价值。确保它是T最慢的放松的1中的至少1至5倍的值 质子。 注意:我们将其设置为40秒，这是在实验中最长的饱和时间（D20）。在这种方式，所有的实验都将保持相同的总"每次扫描"的时间（延迟+饱和时间+脉冲+采集时间）。 </li><li> D1型并将其设置为40秒。 </li><li>通过键入D20并将其设置为40秒设定的饱和时间的第一个值。确定接收机增益（RG）通过键入RGA自动。 </li><li>创建通过键入iexpno下一步实验。键入D20在这个实验中选择20秒的饱和时间。键入RGA自动确定RG。 </li> &lt;利&gt;重复D20 = 10，5，2.5％，1.25，0.625，0.3秒的最后一步。 </li><li>一旦所有的实验的创建，打开第一个和在命令行键入multizg和指定的实验8在这种情况下的数量（ 即 ，multizg 8）。 </li></ol></li><li> SSTD核磁共振实验处理<ol><li>打开从EXPNO 1集合的PROCNO 1（方法号）（实验号）（具有较高的饱和时间）。 </li><li>在命令行中键入磅并将其值设置为1.5。 注:对于具有非常高的信号 - 噪声比这个值能够减少光谱;相反地​​，它可以用于嘈杂实验可以增加，如果光谱分辨率不会受到严重影响。 </li><li>在PROCNO = 2（ 图10）命令行中键入EFP和工艺FID＃= 1（"关于共振"谱）。 </li><li>通过点击交互式相位修正 b校正实验的相utton并保存为一个二维实验。保存并退出（ 图11）。 </li><li>在命令行中键入代表1转到PROCNO 1。 </li><li>在PROCNO = 3（ 图12）命令行中键入EFP和工艺FID＃= 2（"非共振"谱）。 </li><li>在命令行键入.MD然后代表2，以显示与两个处理光谱的多个显示窗口:2（一个在中间饱和的信号）和3（其中饱和脉冲串在40 ppm的施加一个）（ 图13）。 </li><li>点击一个三角征（ 图13）来计算差谱并将其保存在PROCNO 4.退出多个显示窗口的按钮。 </li><li>选择用于在左侧（在其中将观察到饱和，由于化学交换过程转移处的信号）的信号的积分的范围。总是PROCNO 3和4 PROCNO同一区域整合。 <br/&gt;注:在该实验中所用的积分范围是2.55 - 2.67 ppm的。 </li><li>一旦整合，进入"积分"选项卡中的每个实验和复制的价值"积分[ABS]"（ 图14）。 </li><li>通过在PROCNO 3.积分即ηSSTD的40秒（ηSSTD =自旋饱和转移差异参数）的饱和时间的值除以在PROCNO 4的积分。21 </li><li>用同样的方法用不同的饱和次实验的其余部分。 </li></ol></li></ol> 4.数据分析30 <ol><li>对数据的分析来获取动力学参数<ol><li>画出获得ηSSTD值与饱和的时间。21 </li><li>执行指数拟合到所获得的曲线调节到方程 <img alt="式（1）" src="/files/ftp_upload/54499/54499eq1.jpg" /> <img a所述="公式2"SRC ="/文件/ ftp_upload / 54499 / 54499eq2.jpg"/&gt; <img alt="公式3" src="/files/ftp_upload/54499/54499eq3.jpg" /> = <img alt="公式4" src="/files/ftp_upload/54499/54499eq4.jpg" />在很长的饱和时间 t =时间</li><li>计算ηSSTD MAX和δ的值，并用它们来计算该速率常数根据如下方程式弛豫时间（T 1A）的值（k）和: <img alt="公式5" src="/files/ftp_upload/54499/54499eq5.jpg" /> ŧ1A =旋A的纵向弛豫时间常数 K =相互现场交流动力学速率常数<ol><li>由获得动力学速率常数: <img alt="公式6" src="/files/ftp_upload/54499/54499eq6.jpg" /></li></ol></li></ol></li><li>情节的Eyring获得热力学参数<ol><li>情节LN（K / T）对1 / T（T =绝对温度），使用母牛的值<html>在不同温度下抽动速度。 </li><li>执行线性拟合来调整所得到的Eyring方程中的数据: <img alt="公式7" src="/files/ftp_upload/54499/54499eq7.jpg" /> <img alt="式（8）" src="/files/ftp_upload/54499/54499eq8.jpg" /> <img alt="公式9" src="/files/ftp_upload/54499/54499eq9.jpg" /> <img alt="10式" src="/files/ftp_upload/54499/54499eq10.jpg" /> R =气体常数 KB = Boltzmann常数 T =绝对温度</li><li>计算热力学参数ΔH≠和ΔS≠。 </li><li>计算EA（298）和ΔG值≠使用以下公式（298）: <img alt="11式" src="/files/ftp_upload/54499/54499eq11.jpg" /> <img alt="12式" src="/files/ftp_upload/54499/54499eq12.jpg" /> S / ftp_upload / 54499 / 54499eq13.jpg"/&gt; <img alt="14式" src="/files/ftp_upload/54499/54499eq14.jpg" /> </li></ol></li></ol>

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The authors declare that they have no competing financial interests.

One of the more obvious advantages of this methodology is that the rate constants and the relaxation time for a given temperature can be obtained with a single set of experiments, with a robust pulse sequence (the same used for STD experiments to study protein-ligand interactions, which is typically found within the available set of experiments from the spectrometer manufacturer). This simplifies the experimental setup since there is no need to measure T1 or reach steady state saturation. Besides, it is remarkable that this method does not depend on the magnet strength, as coalescence methods. On the other hand, the main limitation is that this technique cannot be applied to chemical exchange processes too fast or too slow, which would depend on the temperature range of the NMR machine or the solvents used.
This new technique for the calculation of kinetic parameters can be applied to a great variety of substrates and its applicability has already been demonstrated with some interesting molecules.21 The kinetic parameters of the 4-N,N-dimethylamido[2.2]paracyclophane, a challenging substrate in which the signal of one of the methyl groups of interest is overlapped with other signals from the molecule, were successfully calculated using SSTD NMR. Interestingly, this methodology can be applied as long as one of the signals of study is isolated. SSTD NMR is also a useful protocol for the calculation of kinetic parameters in molecules in which the coalescence temperature is so high that the molecule decomposes before reaching it. This is the case with PtCl2(dimethylallene)(pyridine), in which the methodology was successfully applied without the need of reaching coalescence. The choice of solvents and temperatures is critical to obtain good results, since the chemical exchange rates can vary significantly with these parameters. Moreover, in addition to the criteria in a normal NMR experiment, key steps in a SSTD NMR experiment are the selectivity of the irradiation as well as the temperature control. Both factors have to be precise to guarantee the success of the experiment.
The representative results presented here are for the kinetics of intramolecular chemical exchange, but the technique can also be applied to study the kinetics of intermolecular chemical exchange and also ligand exchange, common processes in the dynamic behavior of transition metal complexes. 
Finally, providing a proper modification of the equations is made,32 this method could be extended to deal with multi-site exchange and unequal populations, as it has been done in former double resonance experiments,8-9 increasing the usefulness of this technique for the study of chemical exchange processes in challenging compounds.

化学交换通常是指任何分子间或分子内的方法，其中一个核从一个环境移动到另一个，其中其核磁共振参数（化学位移，标量偶合，偶极耦合，松弛率）不同。有有机和有机分子（ 例如，在联芳基旋转障碍，环翻转障碍和构象平衡，氮反转，配体结合，简配体交换和互变异构）化学交换的例子不胜枚举1-3化学汇率相关交换过程的屏障的热力学，因此，其研究是至关重要的，以了解这些系统的分子动力学。 核磁共振动态交换的经典标志是在NMR信号随着温度的变化的线形了戏剧性的变化。在低温下，该过程是缓慢的，两个不同的化学位移是安装前后VED。在高温下，这两个信号合并成一个信号，它被称为"聚结"。在中间温度时，信号变得非常广泛。核磁共振谱的化学交换这种敏感性使得NMR一个非常强大的方法来研究分子动力学解决方案。两种方法已被采用，主要在溶液中的动态过程的研究。线形分析，4-7和自旋饱和转移实验8-9此外，它也是值得一提的反转传输方法10，投洽会项目11直接提取速率常数，这是简单的系统交换测量相对有效的办法。虽然这些方法在大多数情况下，得到了很好的效果，它们，然而，有许多缺点。该线形态分析的主要缺点是在一些样品中达成合并所需要的高温。12，主要要考虑的问题时，CArrying出自旋饱和转移实验是:到达交换位点之间的稳态饱和转移所需的很长的饱和时间，并且需要确定的纵向弛豫时间常数，T 1，这是很困难的，如果有不同的重叠在研究的区域信号。13 作为我们在有机金属机制调查的一部分，14-16我们组正在研究铂-丙二烯络合物在溶液中的fluxional行为。这是一个复杂的任务，包括在至少三个不同的过程，其中之一是金属的丙二烯轴线之一左右的π面交换或旋转。我们遇到的正常的VT实验和已经在类似的系统之前采用线形分析技术，17-19不适合于我们的研究中，由于在我们的铂-丙二烯络合物的非常缓慢的旋转，使得的聚结温度SIG的兴趣比络合物分解的温度高良。 为了克服这一限制，我们开发和最近报道了新的NMR协议（SSTD NMR）研究相互现场的化学交换过程。20顾名思义本方法结合使用的小分子的自旋饱和转移的方法，用饱和转移差异核磁共振方法通过测量沿发生化学交换小分子日趋饱和时间（积曲线）瞬态自旋饱和转移用于蛋白质-配体相互作用的研究中，21-24。 用这种新的方法（SSTD NMR）我们已经表明，我们可以得到超过传统方法的一些额外的优点小有机和有机金属分子的分子内的化学交换的动力学参数:不需要的信号的聚结，因此，更灵活的温度范围内可以使用在研究中;信号重叠不干扰，虽然交换共振中的至少一个应隔离;没有必要测量Ť1或达到稳态饱和;速率常数的值被直接测量，并在相同的实验，获得Ť1值，只用一组实验。所述SSTD核磁共振方法的另一个显着的优点是，相对于线形分析，动力学速率常数的测定是不通过与高磁场相关联的聚结温度的增加的限制。因此，我们的方法，然后很好拨到低和高磁场。本文旨在帮助新用户使用这种新方法，以自己的系统进行化学交换，并介绍了样品制备，实验装置，数据采集，并在一个简单的有机分子的数据处理和分析的例子。

<table><tbody><tr><td>&lt;em&gt;N,N&lt;/em&gt;-dimethylacetamide</td><td>Aldrich</td><td>38840</td><td>Acute toxicity</td></tr><tr><td>Toluene-&lt;em&gt;d&lt;sub&gt;8&lt;/sub&gt;&lt;/em&gt;</td><td>Fluorochem</td><td>D-005</td><td>Flammable and toxic</td></tr><tr><td>500 MHz 7&quot; Select Series NMR Tubes</td><td>GPE LTD</td><td>S-5-500-7</td><td></td></tr><tr><td>TopSpin 2.1</td><td>TopSpin program, Bruker Corp., http://www.bruker.com/products/mr/nmr/nmr-software/software/topspin/ (2015).</td><td></td><td></td></tr><tr><td>Origin 6.0</td><td>Origin 6.0 software, OriginLab Corp., http://originlab.com.</td><td></td><td></td></tr><tr><td>Bruker Avance III 500 MHz fitted with 5 mm broadband observed BBFOplus Z-gradient SmartProbeTM probe</td><td>&amp;nbsp;Bruker Corp., http://www.bruker.com</td><td></td><td></td></tr><tr><td>Bruker Avance I 500 MHz Inverse Triple Resonance NMR spectrometer fitted with a 5 mm TXI Z-gradient probe</td><td>&amp;nbsp;Bruker Corp., http://www.bruker.com</td><td></td><td></td></tr><tr><td>Ceramic Spinner standardbore shimsystems (5 mm)</td><td>&amp;nbsp;Bruker Corp., http://www.bruker.com</td><td>H00804</td><td></td></tr></tbody></table>

spin saturation transfer difference nmr (sstd nmr): a new tool to obtain kinetic parameters of chemical exchange processes

该协议详细介绍了新的自旋饱和转移差异核磁共振协议（SSTD NMR），最近在我们的小组开发研究，是很难用传统的方法来分析相互现场的化学交换过程。顾名思义，该方法中，通过测定瞬态自旋饱和转移沿增加饱和时间（建立结合用于小分子的自旋饱和转移的方法，用饱和转移差异为蛋白 - 配体相互作用的研究采用（STD）NMR法-up曲线）在发生化学交换小的有机和有机分子。 这种方法比现有的优点是:没有必要到达交换信号的聚结;该方法可以，只要可以应用作为交换位点是分离的一个信号;没有必要测量Ť1或达到稳态饱和;速率常数VA梅毒被直接测量，并且在相同的实验中获得Ť1值，只用一组实验。 为了测试该方法，我们研究了N，N- -dimethylamides的受阻旋转，对于其可用于比较大量的数据的动态。使用SSTD得到的热力学参数非常类似于所报告的那些（自旋饱和转移技术和线形分析）。该方法可以适用于无法通过以前的方法来研究更有挑战性基板。 我们设想，在简单的实验设置，并且该方法的广泛适用性极大各种基材将使这个之间无核磁共振广泛的专业知识的有机和有机金属化学家的常用技术。

所述SSTD NMR技术是在N，N-酰胺键的旋转施加的动力学参数的计算二甲基乙酰胺。21这31个简单的例子为哪些用于比较大量的数据可以在文献中找到。 周围的酰胺键的受阻旋转，由于在共振形式部分双键特征，区别在1 H-NMR光谱均为甲基成两个信号（2.61和22.5℃下2.17 ppm的）。在2.17分钟（我B）中的甲基的信号的自旋饱和导致其在1 H-NMR信号的消失。在我B，饱和其他甲基（我A）的传输的饱和由于内部旋转处理可以通过的1 H的强度的信号的下降在2.61 ppm的被观察到。该magnitu这种减少的日将取决于饱和时间。 图15示出了在22.5℃下的N，N-二甲基乙酰胺的1 H NMR谱，和扩展显示没有光谱（a）和与（b）该甲基的饱和基在2.17 ppm时，以及在差异谱（c）中，用于计算ηSSTD的值。的ηSSTD因子计算由（a）中，在协议中解释了我A的光谱的积分值除以我A在SSTD NMR谱（c）该积分的值。所获得的ηSSTD在不同温度下的每个饱和时间为值被收集在表1中。ηSSTD的相对于饱和时间所获得的值的曲线图，得到在其中一个平台在较高的饱和倍达到指数曲线。为一定的温度，在曲线的指数拟合允许速率的计算常数（k）和所测量的信号（T 1A）（ 图16）。的1 H弛豫时间图17显示所有得到的曲线与拟合得到第k和T 1A值一起。 最后，LN的积（K / T）对1 / T和配合到的Eyring方程（ 图18）被用来计算活化的焓和熵。所确定的激活参数示于表2中 ，用不同的方法计算出的先前报告的参数一起。 如可在表2中可以观察到，用自旋饱和转移差异技术（SSTD NMR）中获得的活化参数的值是在与数据优良协议使用其他技术，如SST NMR或以前报道线形态分析。广泛报道ΔS‡值是由于在此参数NMR技术测量的难度。31至于激活参数的其余部分，与我们的方法获得的值不仅确实类似于那些已经报道而且更准确的，因为我们的误差（SD）是在所有情况下要小。 <img alt="图1" src="/files/ftp_upload/54499/54499fig1.jpg" /> 图1:输入 RPAR 实验之后列表 。图中显示了其中STDDIFFESGP应选择不同的参数集。 <a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图2" src="/files/ftp_upload/54499/54499fig2.jpg" /><br/&gt; 图2:。采集参数按钮，在一个红色正方形高亮导致不同的脉冲程序的列表<a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig2large.jpg" target="_blank">，请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/54499/54499fig3.jpg" /> 图3:。 脉冲程序列表的图显示了实验（STDDIFF）选定的脉冲程序<a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图4" src="/files/ftp_upload/54499/54499fig4.jpg" /> 图4:弹出窗口90°脉冲校准后出现图中显示的数值标定90。<html> ＃176;脉冲在不同的功率电平。 <a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig4large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图5" src="/files/ftp_upload/54499/54499fig5.jpg" /> 图5:。 在命令行的截图图显示了如何引入校准硬脉冲值<a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig5large.jpg" target="_blank">，请点击此处查看该图的放大版本。</a> <img alt="图6" src="/files/ftp_upload/54499/54499fig6.jpg" /> 图6: 对整形脉冲的长度值图显示了如何引入值成形脉冲的长度。<html> g6large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 <img alt="图7" src="/files/ftp_upload/54499/54499fig7.jpg" /> 图7:。 采集参数图显示了电源参数， <a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig7large.jpg" target="_blank">请点击这里查看该图的放大版本。</a> <img alt="图8" src="/files/ftp_upload/54499/54499fig8.jpg" /> 图8:为形脉冲参数的脉冲形状的值将在13行介绍<a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig8large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <html> PLOAD / 54499 / 54499fig9.jpg"/&gt; 。图9:照射频率列表的数字包括在3第一行如下的数据: 行1 P（表示后面的数据是用ppm）; 行2 中的信号的频率，以ppm的照射，测得 。 在3.1.1;行3.40 ppm的 （即远离化合物的1小时，这样的信号在频率并不影响光谱辐射的频率） <a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig9large.jpg" target="_blank">点击此处查看该图的放大版本。</a> <img alt="图10" src="/files/ftp_upload/54499/54499fig10.jpg" /> 图10: 第一个FID的处理由图可知，键入EFP后出现的弹出窗口。<html> NK"&gt;点击此处查看该图的放大版本。 <img alt="图11" src="/files/ftp_upload/54499/54499fig11.jpg" /> 图11:。 相位校正屏幕截图显示了手动相位校正窗口<a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig11large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图12" src="/files/ftp_upload/54499/54499fig12.jpg" /> 图12: 在第二FID加工的数字显示，键入EFP后出现的弹出窗口。 <a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig12large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 图13"SRC ="/文件/ ftp_upload / 54499 / 54499fig13.jpg"/&gt; 图13:光谱2和3的按钮，在红色正方形突出了多种显示的是一个计算差值光谱。 <a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig13large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图14" src="/files/ftp_upload/54499/54499fig14.jpg" /> 图14:。积分卡图显示了绝对和相对积分值<a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig14large.jpg" target="_blank">，请点击此处查看该图的放大版本。</a> <img alt="图15" src="/files/ftp_upload/54499/54499fig15.jpg" /> 图15: 结构和 1 </stron<html> g&gt;的氮 H-NMR 光谱 ， 甲苯-d 8，N-二甲基乙22.5℃（a）由照射前2.13至2.66 ppm为单位的区域的1 H NMR扩张。相同的区域（b）的膨胀甲基的照射后在2.17 ppm的。 （ 三 ）差光谱[（A） - （B）]。 <a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig15large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图16" src="/files/ftp_upload/54499/54499fig16.jpg" /> 图16:ηSSTD 的情节 和它的指数拟合在278 K.转载自职权21与皇家化学学会许可的证明资料的例子 。http://ecsource.jove.com/files/ftp_upload/54499/54499fig16large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 <img alt="图17" src="/files/ftp_upload/54499/54499fig17.jpg" /> 图17: 地块 ηSSTD 主场迎战在不同温度下的饱和时间，图中显示了N，N-二甲基乙酰胺和所获得的速率常数和弛豫时间的表中的情节。 <a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig17large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图18" src="/files/ftp_upload/54499/54499fig18.jpg" /> 图18: 阴谋的Eyring图显示了N，N-二甲基乙酰胺剧情。 <a href="http://ecsource.jove.com/files/ftp_upload/54499/54499fig18large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody><tr><td rowspan="2"> ŧSAT（秒） </td><td> ηSSTD </td><td> ηSSTD </td><td> ηSSTD </td><td> ηSSTD </td><td> ηSSTD </td><td> ηSSTD </td><td> ηSSTD </td></tr><tr><td> （T = 278 K） </td><td> （T = 283 K） </td><td> （T = 285.5 K） </td><td> （T = 288 K） </td><td> （T = 290.5 K） </td><td> （T = 293 K） </td><td> （T = 295.5 K） </td></tr><tr><td> 40 </td><td> 0.2526 </td><td> 0.3957 </td><td> 0.4671 </td><td> 0.5461 </td><td> 0.626 </td><td> 0.6969 </td><td> 0.7535 </td></tr><tr><td> 20 </td><td> 0.2526 </td><td> 0.3957 </td><td> 0.4671 </td><td> 0.5461 </td><td> 0.626 </td><td> 0.6969 </td><td> 0.7535 </td></tr><tr><td> 10 </td><td> 0.2383 </td><td> 0.3806 </td><td> 0.4537 </td><td> 0.5355 </td><td> 0.6199 </td><td> 0.6969 </td><td> 0.7535 </td></tr><tr><td>五</td><td> 0.1904 </td><td> 0.3193 </td><td> 0.3919 </td><td> 0.481 </td><td> 0.5734 </td><td> 0.6638 </td><td> 0.7318 </td></tr><tr><td> 2.5 </td><td> 0.1263 </td><td> 0.2204 </td><td> 0.2812 </td><td> 0.3589 </td><td> 0.4449 </td><td> 0.5461 </td><td> 0.626 </td></tr><tr><td> 1.25 </td><td> 0.0761 </td><td> 0.1353 </td><td> 0.171 </td><td> 0.2247 </td><td> 0.2868 </td><td> 0.3732 </td> &lt;TD&gt; 0.4449 </td></tr><tr><td> 0.625 </td><td> 0.0467 </td><td> 0.0739 </td><td> 0.099 </td><td> 0.1327 </td><td> 0.171 </td><td> 0.2291 </td><td> 0.2758 </td></tr><tr><td> 0.3 </td><td> 0.0238 </td><td> 0.044 </td><td> 0.0472 </td><td> 0.0644 </td><td> 0.0847 </td><td> 0.1169 </td><td> 0.1463 </td></tr></tbody></table> 表1:ηSSTD的值的表格示出了在温度278-295.5 K的范围在不同的饱和时间N，N-二甲基乙酰胺中得到的值<table border="0" cellpadding="0" cellspacing="0" width="585"><colgroup><col /><col span="5" /></colgroup><tbody><tr height="34"><td height="34" style="height:34px;width:145px;"> 方法 </td><td style="width:88px;"> SSTD NMR </td><td rowspan="2" style="width:88px;"> SST NMR 31 </<html> TD&gt; <td style="width:88px;"> 线形分析 </td><td style="width:88px;"> 线形分析 </td><td style="width:88px;"> 线形分析 </td></tr><tr height="22"><td height="22" style="height:22px;width:145px;"> 参数 </td><td style="width:88px;"> （这项工作） </td><td style="width:88px;"> （1 H NMR）4 </td><td style="width:88px;"> （1 H NMR）5- </td><td style="width:88px;"> （13 C NMR）6 </td></tr><tr height="21"><td height="21" style="height:21px;width:145px;"> Ë298（KJ摩尔-1） </td><td style="width:88px;"> 79.7±0.1 </td><td style="width:88px;"> 73.1±1.4 </td><td style="width:88px;"> 70.5±1.7 </td><td style="width:88px;"> 82.0±1.3 </td><td style="width:88px;"> 79.5±0.4 </td></tr><tr height="21">21px;宽度:145px;"&gt;ΔH‡（KJ摩尔-1） </td><td style="width:88px;"> 77.2±0.1 </td><td style="width:88px;"> 70.6±1.4 </td><td style="width:88px;"> 68 </td><td style="width:88px;"> 79.5±0.4 </td><td style="width:88px;"> 76.6±0.4 </td></tr><tr height="21"><td height="21" style="height:21px;width:145px;"> ΔS‡（J摩尔-1 K -1） </td><td style="width:88px;"> 11.5±0.4 </td><td style="width:88px;"> -10.5±5.0 </td><td style="width:88px;"> -15.0±5.1 </td><td style="width:88px;"> 13±8 </td><td style="width:88px;"> 3±4 </td></tr><tr height="21"><td height="21" style="height:21px;width:145px;"> ΔG‡298（KJ摩尔-1） </td><td style="width:88px;"> 73.8±0.1 </td><td style="width:88px;"> 73.7±2.0 </td><td style="width:88px;"> 720.5 </td><td style="width:88px;"> 75.3±0.4 </td><td style="width:88px;"> 75.7±0.4 </td></tr><tr height="21"><td height="21" style="height:21px;width:145px;"> 溶剂 </td><td style="width:88px;">允差D 8 </td><td style="width:88px;">允差D 8 </td><td style="width:88px;"> 四氯化碳 </td><td style="width:88px;">丙酮-d 6 </td><td style="width:88px;">整齐</td></tr></tbody></table> 表2: 激活参数表显示N的内旋的激活参数，N-二甲基乙酰胺通过与使用用于分析不同核磁共振方法获得的相同的参数进行比较的SSTD NMR法获得在此表4,5,6误差。参考标准偏差误差（SD）。 （从21引用转载来自皇家SOC许可化学iety）。

Watch this Scientific Journal Video about Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes at JoVE.com

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

A detailed protocol describing the SSTD NMR method is presented here to help new users apply this new method to obtain the kinetic parameters of their own systems undergoing chemical exchange.

自旋饱和转移差异核磁共振（NMR SSTD）:一种新的工具来获得化学交换过程的动力学参数

This detailed protocol describes the new Spin Saturation Transfer Difference Nuclear Magnetic Resonance protocol (SSTD NMR), recently developed in our ...

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Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Advanced Nuclear Magnetic Resonance Spectroscopy

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17.7K 次观看.  University of East Anglia. A detailed protocol describing the SSTD NMR method is presented here to help new users apply this new method to obtain the kinetic parameters of their own systems undergoing chemical exchange.

视频: Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy

Supramolecular protein assemblies play fundamental roles in biological processes ranging from host-pathogen interaction, viral infection to the propagation of neurodegenerative disorders. Such assemblies consist in multiple protein subunits organized in a non-covalent way to form large macromolecular objects that can execute a variety of cellular functions or cause detrimental consequences. Atomic insights into the assembly mechanisms and the functioning of those macromolecular assemblies remain often scarce since their inherent insolubility and non-crystallinity often drastically reduces the quality of the data obtained from most techniques used in structural biology, such as X-ray crystallography and solution Nuclear Magnetic Resonance (NMR). We here present magic-angle spinning solid-state NMR spectroscopy (SSNMR) as a powerful method to investigate structures of macromolecular assemblies at atomic resolution. SSNMR can reveal atomic details on the assembled complex without size and solubility limitations. The protocol presented here describes the essential steps from the production of 13C/15N isotope-labeled macromolecular protein assemblies to the acquisition of standard SSNMR spectra and their analysis and interpretation. As an example, we show the pipeline of a SSNMR structural analysis of a filamentous protein assembly.

Structures of supramolecular protein assemblies at atomic resolution are of high relevance because of their crucial roles in a variety of biological phenomena. Herein, we present a protocol to perform high-resolution structural studies on insoluble and non-crystalline macromolecular protein assemblies by magic-angle spinning solid-state nuclear magnetic resonance spectroscopy (MAS SSNMR).

固体核磁共振波谱法研究高分子组件的原子尺度结构

Supramolecular protein assemblies play fundamental roles in biological processes ranging from host-pathogen interaction, viral infection to the ...

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Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR

The main limitation of NMR-based investigations is low sensitivity. This prompts for long acquisition times, thus preventing real-time NMR measurements of metabolic transformations. Hyperpolarization via dissolution DNP circumvents part of the sensitivity issues thanks to the large out-of-equilibrium nuclear magnetization stemming from the electron-to-nucleus spin polarization transfer. The high NMR signal obtained can be used to monitor chemical reactions in real time. The downside of hyperpolarized NMR resides in the limited time window available for signal acquisition, which is usually on the order of the nuclear spin longitudinal relaxation time constant, T1, or, in favorable cases, on the order of the relaxation time constant associated with the singlet-state of coupled nuclei, TLLS. Cellular uptake of endogenous molecules and metabolic rates can provide essential information on tumor development and drug response. Numerous previous hyperpolarized NMR studies have demonstrated the relevancy of pyruvate as a metabolic substrate for monitoring enzymatic activity in vivo. This work provides a detailed description of the experimental setup and methods required for the study of enzymatic reactions, in particular the pyruvate-to-lactate conversion rate in presence of lactate dehydrogenase (LDH), by hyperpolarized NMR.

The sensitivity enhancement provided by dissolution dynamic nuclear polarization (DNP) enables following metabolic processes in real time by NMR and MRI. The characteristics and performances of a dedicated dissolution DNP setup designed for study enzymatic reactions are discussed.

溶出动态核极化仪器用NMR实时酶反应速率测量

The main limitation of NMR-based investigations is low sensitivity. This prompts for long acquisition times, thus preventing real-time NMR measurements of ...

化学

Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels

Ion channel gating is a stimulus-driven orchestration of protein motions that leads to transitions between closed, open, and desensitized states. Fundamental to these transitions is the intrinsic flexibility of the protein, which is critically modulated by membrane lipid-composition. To better understand the structural basis of channel function, it is necessary to study protein dynamics in a physiological membrane environment. Electron Paramagnetic Resonance (EPR) spectroscopy is an important tool to characterize conformational transitions between functional states. In comparison to NMR and X-ray crystallography, the information obtained from EPR is intrinsically of lower resolution. However, unlike in other techniques, in EPR there is no upper-limit to the molecular weight of the protein, the sample requirements are significantly lower, and more importantly the protein is not constrained by the crystal lattice forces. Therefore, EPR is uniquely suited for studying large protein complexes and proteins in reconstituted systems. In this article, we will discuss general protocols for site-directed spin labeling and membrane reconstitution using a prokaryotic proton-gated pentameric Ligand-Gated Ion Channel (pLGIC) from Gloeobacter violaceus (GLIC) as an example. A combination of steady-state Continuous Wave (CW) and Pulsed (Double Electron Electron Resonance-DEER) EPR approaches will be described that will enable a complete quantitative characterization of channel dynamics.

This article describes methods for site-directed spin labeling and reconstitution of pentameric ligand-gated channels for Electron Paramagnetic Resonance studies. This protocol can be adapted for any membrane protein. The reconstitution method described here can also be used for patch-clamp measurements of macroscopic and single-channel currents in a defined lipid system.

定点自旋标记和五聚体配体门控离子通道的EPR光谱研究

Ion channel gating is a stimulus-driven orchestration of protein motions that leads to transitions between closed, open, and desensitized states. ...

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging

A method is demonstrated to monitor macroscopic translational diffusion using electron paramagnetic resonance (EPR) imaging. A host-guest system with nitroxide spin probe 3-(2-Iodoacetamido)-2,2,5,5-tetramethyl-1-pyrrolidinyloxy (IPSL) as a guest inside the periodic mesoporous organosilica (PMO) aerogel UKON1-GEL as a host and ethanol as a solvent is used as an example to describe the protocol. Data is shown from a previous publication, where the protocol has been applied to both IPSL and Tris(8-carboxy-2,2,6,6-perdeutero-tetramethyl-benzo[1,2-d:4,5-d&#8242;]bis(1,3)dithiole) methyl (Trityl) as guest molecules and UKON1-GEL and SILICA-GEL as host systems. 
A method is shown to prepare aerogel samples that cannot be synthesized directly in the sample tube for measurement due to a size change during synthesis. The aerogel is attached to sample tubes using heat shrink tubing and a pressure cooker to reach the necessary temperature without evaporating the solvent in the process. The method does not assume a clearly defined initial distribution of guest molecules at the start of the measurement. Instead, it requires a reservoir on top of the aerogel and experimentally determines the influx rate during data analysis.
The diffusion is monitored continually over a period of 20 hr by recording the 1d spin density profile within the sample. The spectrometer settings for the imaging experiment are described quantitatively. Data analysis software is provided to take the resonator sensitivity profile into account and to numerically solve the diffusion equation. The software determines the macroscopic translational diffusion coefficient by least square minimization of the difference between the experiment and the numerical solution of the diffusion equation.

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging

A protocol for the in situ monitoring of the diffusion of guest molecules in porous media using electron paramagnetic resonance (EPR) imaging is presented.

在多孔介质中使用电子顺磁共振成像客体分子扩散的原位监测

A method is demonstrated to monitor macroscopic translational diffusion using electron paramagnetic resonance (EPR) imaging. A host-guest system with ...

15N CPMG Relaxation Dispersion for the Investigation of Protein Conformational Dynamics on the &#181;s-ms Timescale

Protein conformational dynamics play fundamental roles in regulation of enzymatic catalysis, ligand binding, allostery, and signaling, which are important biological processes. Understanding how the balance between structure and dynamics governs biological function is a new frontier in modern structural biology and has ignited several technical and methodological developments. Among these, CPMG relaxation dispersion solution NMR methods provide unique, atomic-resolution information on the structure, kinetics, and thermodynamics of protein conformational equilibria occurring on the &#181;s-ms timescale. Here, the study presents detailed protocols for acquisition and analysis of a&#160;15N relaxation dispersion experiment. As an example, the pipeline for the analysis of the &#181;s-ms dynamics in the C-terminal domain of bacteria Enzyme I is shown.

15N CPMG Relaxation Dispersion for the Investigation of Protein Conformational Dynamics on the  &#181;s-ms Timescale

Here, a detailed description of the protocol implemented in the laboratory for acquisition and analysis of 15N relaxation dispersion profiles by solution NMR spectroscopy is provided.

15N CPMG 放松分散，用于研究 μs-ms 时间尺度上的蛋白质符合性动力学

Protein conformational dynamics play fundamental roles in regulation of enzymatic catalysis, ligand binding, allostery, and signaling, which are important ...

Practical Aspects of Sample Preparation and Setup of 1H R1&#961; Relaxation Dispersion Experiments of RNA

RNA is a highly flexible biomolecule, wherein changes in structures play crucial roles in the functions that RNA molecules execute as cellular messengers and modulators. While these dynamic states remain hidden to most structural methods, R1&#961; relaxation dispersion (RD) spectroscopy allows the study of conformational dynamics in the micro- to millisecond regime at atomic resolution. The use of 1H as the observed nucleus further expands the time regime covered and gives direct access to hydrogen bonds and base pairing.
The challenging steps in such a study are high-purity and high-yield sample preparation, potentially 13C- and 15N-labeled, as well as setup of experiments and fitting of data to extract population, exchange rate, and secondary structure of the previously invisible state. This protocol provides crucial hands-on steps in sample preparation to ensure the preparation of a suitable RNA sample and setup of 1H R1&#961; experiments with both isotopically labeled and unlabeled RNA samples.

We present a protocol to measure micro- to millisecond dynamics on 13C/15N-labeled and unlabeled RNA with 1H R1&#961; relaxation dispersion nuclear magnetic resonance (NMR) spectroscopy. The focus of this protocol lies in high-purity sample preparation and setup of NMR experiments.

1H R1 + RNA 放松分散实验样品制备和设置的实用方面

RNA is a highly flexible biomolecule, wherein changes in structures play crucial roles in the functions that RNA molecules execute as cellular messengers ...

Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo

We demonstrate a superior method of 2D spectral-spatial imaging of stable radical reporter molecules at 250 MHz using rapid-scan electron-paramagnetic-resonance (RS-EPR), which can provide quantitative information under in vivo conditions on oxygen concentration, pH, redox status and concentration of signaling molecules (i.e., OH&#8226;, NO&#8226;). The RS-EPR technique has a higher sensitivity, improved spatial resolution (1 mm), and shorter acquisition time in comparison to the standard continuous wave (CW) technique. A variety of phantom configurations have been tested, with spatial resolution varying from 1 to 6 mm, and spectral width of the reporter molecules ranging from 16 &#181;T (160 mG) to 5 mT (50 G). A cross-loop bimodal resonator decouples excitation and detection, reducing the noise, while the rapid scan effect allows more power to be input to the spin system before saturation, increasing the EPR signal. This leads to a substantially higher signal-to-noise ratio than in conventional CW EPR experiments.

Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo

A new electron paramagnetic resonance (EPR) method, rapid scan EPR (RS-EPR), is demonstrated for 2D spectral spatial imaging which is superior to the traditional continuous wave (CW) technique and opens new venues for in vivo imaging. Results are demonstrated at 250 MHz, but the technique is applicable at any frequency.

快速扫描电子顺磁共振打开新的途径成像生理重要参数<em&gt;在体内</em

We demonstrate a superior method of 2D spectral-spatial imaging of stable radical reporter molecules at 250 MHz using rapid-scan ...

生物工程

High-Resolution Studies of Proteins in Natural Membranes by Solid-State NMR

Membrane proteins are vital for cell function and thus represent important drug targets. Solid-state Nuclear Magnetic Resonance (ssNMR) spectroscopy offers a unique access to probe the structure and dynamics of such proteins in biological membranes of increasing complexity. Here, we present modern solid-state NMR spectroscopy as a tool to study structure and dynamics of proteins in natural lipid membranes and at atomic scale. Such spectroscopic studies profit from the use of high-sensitivity ssNMR methods, i.e., proton-(1H)-detected ssNMR and DNP (Dynamic Nuclear Polarization) supported ssNMR. Using bacterial outer membrane beta-barrel protein BamA and the ion channel KcsA, we present methods to prepare isotope-labeled membrane proteins and to derive structural and motional information by ssNMR.

This work details robust basic routines on how to prepare isotope-labeled membrane protein samples and analyze them at high-resolution with modern solid-state NMR spectroscopy methods.

Membrane proteins are vital for cell function and thus represent important drug targets. Solid-state Nuclear Magnetic Resonance (ssNMR) spectroscopy ...

用于聚糖-蛋白质相互作用分析的先进 NMR 技术

Disentangling Glycan-Protein Interactions: Nuclear Magnetic Resonance (NMR) to the Rescue

The interactions of glycans with proteins modulate many events related to health and disease. In fact, the establishment of these recognition events and their biological consequences are intimately related to the three-dimensional structures of both partners, as well as to their dynamic features and their presentation on the corresponding cell compartments. NMR techniques are unique to disentangle these characteristics and, indeed, diverse NMR-based methodologies have been developed and applied to monitor the binding events of glycans with their associate receptors. This protocol outlines the procedures to acquire, process and analyze two of the most powerful NMR methodologies employed in the NMR-glycobiology field, 1H-Saturation transfer difference (STD) and 1H,15N-Heteronuclear single quantum coherence (HSQC) titration experiments, which complementarily offer information from the glycan and protein perspective, respectively. Indeed, when combined they offer a powerful toolkit for elucidating both the structural and dynamic aspects of molecular recognition processes. This comprehensive approach enhances our understanding of glycan-protein interactions and contributes to advancing research in the chemical glycobiology field.

作者聚焦:揭示聚糖分子识别的结构和动力学方面

Here, we present a protocol detailing the acquisition, processing, and analysis of a series of NMR experiments aimed at characterizing protein-glycan interactions in solution. Most common ligand-based and protein-based methodologies are outlined, which undoubtedly contribute to the fields of structural glycobiology and molecular recognition studies.

解开聚糖-蛋白质相互作用:核磁共振 （NMR） 来拯救

The interactions of glycans with proteins modulate many events related to health and disease. In fact, the establishment of these recognition events and ...

自旋饱和转移差异核磁共振（NMR SSTD）:一种新的工具来获得化学交换过程的动力学参数

摘要

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此视频中的章节

固体核磁共振波谱法研究高分子组件的原子尺度结构

溶出动态核极化仪器用NMR实时酶反应速率测量

定点自旋标记和五聚体配体门控离子通道的EPR光谱研究

在多孔介质中使用电子顺磁共振成像客体分子扩散的原位监测

¹⁵N CPMG 放松分散，用于研究 μs-ms 时间尺度上的蛋白质符合性动力学

¹H R_{1 +} RNA 放松分散实验样品制备和设置的实用方面

快速扫描电子顺磁共振打开新的途径成像生理重要参数

High-Resolution Studies of Proteins in Natural Membranes by Solid-State NMR

解开聚糖-蛋白质相互作用:核磁共振（NMR）来拯救

解开聚糖-蛋白质相互作用:核磁共振（NMR）来拯救

自旋饱和转移差异核磁共振（NMR SSTD）:一种新的工具来获得化学交换过程的动力学参数

摘要

探索更多视频

此视频中的章节

固体核磁共振波谱法研究高分子组件的原子尺度结构

溶出动态核极化仪器用NMR实时酶反应速率测量

定点自旋标记和五聚体配体门控离子通道的EPR光谱研究

在多孔介质中使用电子顺磁共振成像客体分子扩散的原位监测

15N CPMG 放松分散，用于研究 μs-ms 时间尺度上的蛋白质符合性动力学

1H R1 + RNA 放松分散实验样品制备和设置的实用方面

快速扫描电子顺磁共振打开新的途径成像生理重要参数

High-Resolution Studies of Proteins in Natural Membranes by Solid-State NMR

解开聚糖-蛋白质相互作用:核磁共振 （NMR） 来拯救

解开聚糖-蛋白质相互作用:核磁共振 （NMR） 来拯救

¹⁵N CPMG 放松分散，用于研究 μs-ms 时间尺度上的蛋白质符合性动力学

¹H R_{1 +} RNA 放松分散实验样品制备和设置的实用方面

解开聚糖-蛋白质相互作用:核磁共振（NMR）来拯救

解开聚糖-蛋白质相互作用:核磁共振（NMR）来拯救