On the analysis of sedimentation velocity in the study of protein complexes

摘要: Sedimentation velocity analytical ultracentrifugation has experienced a significant transformation, precipitated by the possibility of efficiently fitting Lamm equation solutions to experimental data. The precision this approach depends on ability account for imperfections experiment, both regarding sample and instrument. In present work, we explore in more detail relationship between sedimentation process, its detection, model used mathematical data analysis. We focus configurations that produce steep fast-moving boundaries, such as frequently encountered when studying large multi-protein complexes. First, computational tool facilitating analysis heterogeneous samples, introduce strategy partial boundary modeling. It can simplify modeling restricting direct species with coefficients predefined range. Next, examine factors related including magnitude optical aberrations generated out-of-focus solution columns at high protein concentrations, experimentally recorded signature meniscus parameter analysis, consequences limited radial temporal resolution absorbance scanning system. Surprisingly, find errors be caused finite speed commercial optics, exceeding statistical measured than an order magnitude. describe how these effects computationally accounted SEDFIT SEDPHAT.