Simultaneous quantification and identification of individual chemicals in metabolite mixtures by two-dimensional extrapolated time-zero (1)H-(13)C HSQC (HSQC(0)).
Simultaneous quantification and identification of individual chemicals in metabolite mixtures by two-dimensional extrapolated time-zero (1)H-(13)C HSQC (HSQC(0)).
复制标题
通过二维外推时间零（1）H-（13）C HSQC（HSQC（0））同时定量和鉴定代谢物混合物中的单个化学物质。
DOI：
10.1021/ja1095304
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发表时间：
2011-02-16
影响因子：
15
通讯作者：
Markley JL
中科院分区：
文献类型：
--
作者：
Hu K;Westler WM;Markley JL
定量一维（1D）1H NMR光谱法是测定代谢物浓度的有用工具，因为信号强度与分析物的量成正比。然而，复杂代谢物混合物的1D 1H NMR光谱中严重的信号重叠阻碍了准确的定量。一维1H到二维1H − 13 C HSQC的延伸导致了峰沿着13 C维度的分散，并大大减少了峰重叠。虽然2D 1H − 13 C HSQC中的峰比1D 1H NMR光谱中的峰更好地分辨，但在相干转移期间，共振特异性信号衰减会使交叉峰与单个代谢物数量的简单比例丢失。因此，通常通过参考从已知浓度的样品中收集的校准数据来定量单个代谢物的峰。我们在这里表明，从一系列HSQC光谱中获得的数据与递增的重复时间（第一个1H激发脉冲结束到数据采集开始之间的时间）可以外推回零时间，以产生零时间2D 1H − 13 C HSQC光谱（HSQC0），其中信号强度与单个代谢物的浓度成比例。通过参考已知浓度的内标物，可将由交叉峰强度测定的相对浓度转换为绝对浓度。通过归一化强度对HSQC0交叉峰进行聚类，可以识别出与给定浓度下存在的代谢物相对应的那些峰，并且该信息可以帮助将这些峰分配给特定化合物。单个代谢物的浓度测量可以通过平均分配给该代谢物的多个非重叠交叉峰的强度来改进。
Quantitative one-dimensional (1D) 1H NMR spectroscopy is a useful tool for determining metabolite concentrations because of the direct proportionality of signal intensity to the quantity of analyte. However, severe signal overlap in 1D 1H NMR spectra of complex metabolite mixtures hinders accurate quantification. Extension of 1D 1H to 2D 1H−13C HSQC leads to the dispersion of peaks along the 13C dimension and greatly alleviates peak overlapping. Although peaks are better resolved in 2D 1H−13C HSQC than in 1D 1H NMR spectra, the simple proportionality of cross peaks to the quantity of individual metabolites is lost by resonance-specific signal attenuation during the coherence transfer periods. As a result, peaks for individual metabolites usually are quantified by reference to calibration data collected from samples of known concentration. We show here that data from a series of HSQC spectra acquired with incremented repetition times (the time between the end of the first 1H excitation pulse to the beginning of data acquisition) can be extrapolated back to zero time to yield a time-zero 2D 1H−13C HSQC spectrum (HSQC0) in which signal intensities are proportional to concentrations of individual metabolites. Relative concentrations determined from cross peak intensities can be converted to absolute concentrations by reference to an internal standard of known concentration. Clustering of the HSQC0 cross peaks by their normalized intensities identifies those corresponding to metabolites present at a given concentration, and this information can assist in assigning these peaks to specific compounds. The concentration measurement for an individual metabolite can be improved by averaging the intensities of multiple, nonoverlapping cross peaks assigned to that metabolite.
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影响因子：
7.4
作者：
Huaping Mo;Raftery, Daniel
通讯作者：
Raftery, Daniel
影响因子：
7.4
作者：
Akoka, S;Barantin, L;Trierweiler, M
通讯作者：
Trierweiler, M
影响因子：
7.4
作者：
Rai, Ratan Kumar;Tripathi, Pratima;Sinha, Neeraj
通讯作者：
Sinha, Neeraj
DOI：
10.1016/j.jmr.2009.07.004
发表时间：
2009-10
期刊：
Journal of magnetic resonance (San Diego, Calif. : 1997)
影响因子：
--
作者：
Mo H;Harwood J;Zhang S;Xue Y;Santini R;Raftery D
通讯作者：
Raftery D
影响因子：
2.2
作者：
Braun, D;Wüthrich, K;Wider, G
通讯作者：
Wider, G