کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2829159 1570450 2007 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A maximum likelihood approach to two-dimensional crystals
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شناسی مولکولی
پیش نمایش صفحه اول مقاله
A maximum likelihood approach to two-dimensional crystals
چکیده انگلیسی

Maximum likelihood (ML) processing of transmission electron microscopy images of protein particles can produce reconstructions of superior resolution due to a reduced reference bias. We have investigated a ML processing approach to images centered on the unit cells of two-dimensional (2D) crystal images. The implemented software makes use of the predictive lattice node tracking in the MRC software, which is used to window particle stacks. These are then noise-whitened and subjected to ML processing. Resulting ML maps are translated into amplitudes and phases for further processing within the 2dx software package. Compared with ML processing for randomly oriented single particles, the required computational costs are greatly reduced as the 2D crystals restrict the parameter search space. The software was applied to images of negatively stained or frozen hydrated 2D crystals of different crystal order. We find that the ML algorithm is not free from reference bias, even though its sensitivity to noise correlation is lower than for pure cross-correlation alignment. Compared with crystallographic processing, the newly developed software yields better resolution for 2D crystal images of lower crystal quality, and it performs equally well for well-ordered crystal images.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Structural Biology - Volume 160, Issue 3, December 2007, Pages 362–374
نویسندگان
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