Mobli Mehdi, Maciejewski Mark W, Gryk Michael R, Hoch Jeffrey C
Department of Molecular, Microbial, and Structural Biology, University of Connecticut Health Center, 263 Farmington Ave., Farmington, CT 06030-3305, USA.
J Biomol NMR. 2007 Oct;39(2):133-9. doi: 10.1007/s10858-007-9180-8. Epub 2007 Aug 15.
Developments in superconducting magnets, cryogenic probes, isotope labeling strategies, and sophisticated pulse sequences together have enabled the application, in principle, of high-resolution NMR spectroscopy to biomolecular systems approaching 1 megadalton. In practice, however, conventional approaches to NMR that utilize the fast Fourier transform, which require data collected at uniform time intervals, result in prohibitively lengthy data collection times in order to achieve the full resolution afforded by high field magnets. A variety of approaches that involve nonuniform sampling have been proposed, each utilizing a non-Fourier method of spectrum analysis. A very general non-Fourier method that is capable of utilizing data collected using any of the proposed nonuniform sampling strategies is maximum entropy reconstruction. A limiting factor in the adoption of maximum entropy reconstruction in NMR has been the need to specify non-intuitive parameters. Here we describe a fully automated system for maximum entropy reconstruction that requires no user-specified parameters. A web-accessible script generator provides the user interface to the system.
超导磁体、低温探头、同位素标记策略以及复杂脉冲序列的发展共同使得原则上高分辨率核磁共振光谱能够应用于接近1兆道尔顿的生物分子系统。然而,在实际应用中,利用快速傅里叶变换的传统核磁共振方法需要在均匀时间间隔内采集数据,为了达到高场磁体所能提供的全分辨率,数据采集时间长得令人望而却步。已经提出了多种涉及非均匀采样的方法,每种方法都采用非傅里叶光谱分析方法。一种非常通用的非傅里叶方法——最大熵重建,能够利用使用任何一种所提出的非均匀采样策略采集的数据。核磁共振中采用最大熵重建的一个限制因素是需要指定非直观的参数。在此,我们描述了一种用于最大熵重建的全自动系统,该系统无需用户指定参数。一个可通过网络访问的脚本生成器为系统提供用户界面。