Reciprocal-space solvent ̄attening
نویسنده
چکیده
# 1999 International Union of Crystallography Printed in Denmark ± all rights reserved Solvent ̄attening is a powerful tool for improving crystallographic phases for macromolecular structures obtained at moderate resolution, but uncertainties in the optimal weighting of experimental phases and modi®ed phases make it dif®cult to extract all the phase information possible. Solvent ̄attening is essentially an iterative method for maximizing a likelihood function which consists of (i) experimental phase information and (ii) information on the likelihood of various arrangements of electron density in a map, but the likelihood function is generally not explicitly de®ned. In this work, a procedure is described for reciprocalspace maximization of a likelihood function based on experimental phases and characteristics of the electrondensity map. The procedure can readily be applied to phase improvement based on solvent ̄attening and can potentially incorporate information on a wide variety of other characteristics of the electron-density map. Received 17 May 1999 Accepted 22 July 1999
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Reciprocal-space solvent flattening
Solvent flattening is a powerful tool for improving crystallographic phases for macromolecular structures obtained at moderate resolution, but uncertainties in the optimal weighting of experimental phases and modified phases make it difficult to extract all the phase information possible. Solvent flattening is essentially an iterative method for maximizing a likelihood function which consists o...
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