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Recursive direct phasing with reference-beam diffraction.

Qun Shen·Jun Wang
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Abstract

The reference-beam diffraction technique provides a practical way to measure a large number of triplet phases in a standard oscillating-crystal diffraction experiment for protein crystals. The triplet-phase data set from such reference-beam measurements contains a unique phase-occurrence pattern that leads to a new recursive phasing algorithm for the individual structure-factor phases. Application of the new algorithm is demonstrated for tetragonal lysozyme using 7360 triplet phases measured in a reference-beam experiment with a median phase discrepancy of 45 degrees. An electron-density map obtained using this phasing algorithm and the measured triplet phases shows good agreement with the known protein structure.

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AlgorithmsMuramidaseStatic ElectricityX-Ray DiffractionJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Qun Shen, Jun Wang. 2003-04-25. Recursive direct phasing with reference-beam diffraction.. https://doi.org/10.1107/s0907444903003664

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