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Shake-and-Bake applications using simulated reference-beam data for crambin.

C M Weeks·H Xu·H A Hauptman·Q Shen
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Abstract

The Shake-and-Bake method, as implemented in the computer program SnB, has been applied to simulated reference-beam data for the small protein crambin at several resolutions in the range 1.5-3.0 A. Sets of triplet invariants were generated having simulated mean triplet-phase errors from 0 to 60 degrees. Provided that these errors were no larger than 40 degrees, it was possible (at all resolutions tested) to find trial sets of individual Bragg phases with mean errors of 40-45 degrees. At 1.5 A, this could be achieved using only a single reference-beam data set. Peak picking provided useful phase constraints even at the lowest resolution tested. These results suggest that direct methods may be useful in conjunction with reference-beam data at resolutions lower than 1.2 A.

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AlgorithmsComputer SimulationCrystallography, X-RayImage Interpretation, Computer-AssistedPlant ProteinsJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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C M Weeks, H Xu, H A Hauptman, Q Shen. 2000. Shake-and-Bake applications using simulated reference-beam data for crambin.. https://doi.org/10.1107/s0108767300000829

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