We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Improving the convergence rate of a hybrid input-output phasing algorithm by varying the reflection data weight.
- Authors
He, Hongxing; Su, Wu-Pei
- Abstract
In an iterative projection algorithm proposed for ab initio phasing, the error metrics typically exhibit little improvement until a sharp decrease takes place as the iteration converges to the correct high-resolution structure. Related to that is the small convergence probability for certain structures. As a remedy, a variable weighting scheme on the diffraction data is proposed. It focuses on phasing low- and medium-resolution data first. The weighting shifts to incorporate more high-resolution reflections when the iteration proceeds. It is found that the precipitous drop in error metrics is replaced by a less dramatic drop at an earlier stage of the iteration. It seems that once a good configuration is formed at medium resolution, convergence towards the correct highresolution structure is almost guaranteed. The original problem of phasing all diffraction data at once is reduced to a much more manageable one due to the dramatically smaller number of reflections involved. As a result, the success rate is significantly enhanced and the speed of convergence is raised. This is illustrated by applying the new algorithm to several structures, some of which are very difficult to solve without data weighting.
- Subjects
PROTEIN structure; PHASE transitions; HIGH resolution imaging
- Publication
Acta Crystallographica. Section A, Foundations & Advances, 2018, Vol 74, Issue 1, p36
- ISSN
2053-2733
- Publication type
Article
- DOI
10.1107/S205327331701436X