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Improving multiple isomorphous replacement phasing by heavy-atom refinement using solvent-flattened phases.

M A Rould·J J Perona·T A Steitz
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Abstract

Solvent flattening of macromolecular MIR electron density maps is frequently used to improve the quality of the phases and the interpretability of resultant electron density maps. A new method is presented by which the heavy-atom parameters of isomorphous derivatives are refined against these same solvent-flattened phases and is shown to enhance convergence of the parameters by decoupling heavy-atom-parameter adjustment from parent-phase calculation. This approach is described here in the first example of its application in the solution of the glutaminyl-tRNA synthetase-tRNA(Gln)-ATP co-crystal structure.

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Adenosine TriphosphateChemical PhenomenaChemistry, PhysicalCrystallizationGlutamate-tRNA LigaseRNA, Transfer, GluSolventsX-Ray DiffractionJournal Article

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M A Rould, J J Perona, T A Steitz. 1992-09-01. Improving multiple isomorphous replacement phasing by heavy-atom refinement using solvent-flattened phases.. https://doi.org/10.1107/s0108767392003404

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