National Centre for Macromolecular Hydrodynamics, School of Biosciences, University of Nottingham, College Road, Sutton Bonington, LE12 5RD, UK.
Eur Biophys J. 2013 Oct;42(10):777-86. doi: 10.1007/s00249-013-0924-y. Epub 2013 Aug 29.
MultiSig is a newly developed mode of analysis of sedimentation equilibrium (SE) experiments in the analytical ultracentrifuge, having the capability of taking advantage of the remarkable precision (~0.1% of signal) of the principal optical (fringe) system employed, thus supplanting existing methods of analysis through reducing the 'noise' level of certain important parameter estimates by up to orders of magnitude. Long-known limitations of the SE method, arising from lack of knowledge of the true fringe number in fringe optics and from the use of unstable numerical algorithms such as numerical differentiation, have been transcended. An approach to data analysis, akin to 'spatial filtering', has been developed, and shown by both simulation and practical application to be a powerful aid to the precision with which near-monodisperse systems can be analysed, potentially yielding information on protein-solvent interaction. For oligo- and poly-disperse systems the information returned includes precise average mass distributions over both cell radial and concentration ranges and mass-frequency histograms at fixed radial positions. The application of MultiSig analysis to various complex heterogenous systems and potentially multiply-interacting carbohydrate oligomers is described.
多重信号是一种新开发的分析沉降平衡（SE）实验的模式，在分析超速离心机中具有利用显著精度（~0.1%的信号）的主要光学（条纹）系统的能力，从而通过将某些重要参数估计的“噪声”水平降低多达几个数量级来替代现有的分析方法。SE 方法长期存在的限制，源于缺乏对条纹光学中真实条纹数量的了解以及使用不稳定的数值算法（如数值微分），已经被克服。已经开发出一种类似于“空间滤波”的数据分析方法，通过模拟和实际应用证明，它是提高近单分散系统分析精度的有力工具，有可能提供有关蛋白质-溶剂相互作用的信息。对于寡聚和多分散系统，返回的信息包括在细胞径向和浓度范围内的精确平均质量分布以及在固定径向位置的质量频率直方图。描述了将多重信号分析应用于各种复杂的不均匀系统和潜在的多重相互作用的碳水化合物低聚物。
