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Phasing protein structures using the group-subgroup relation.

Luigi Di Costanzo·Federico Forneris·Silvano Geremia·Lucio Randaccio
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Abstract

Diffraction data from two non-isomorphous crystals (forms 1 and 2) of an artificial protein with a four-helix bundle motif, di-Co(II)-DF1-L13A, have been collected using synchrotron radiation. The phase of form 1 has been assigned using the group and minimal non-isomorphic supergroup relation between the space group of the previously determined di-Mn(II)-DF1-L13G structure and the space group of this form. This unconventional method of solving the phase problem has also been tested with form 2 using a reverse relation. The structure of the latter form has been solved using the group and maximal non-isomorphic subgroup relation with the space group of form 2 of the analogous dimanganese protein. This application has shown that this phasing method can be used for solving the protein structures of polymorphic crystals as an alternative to the molecular-replacement method.

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Amino Acid MotifsBinding SitesDimerizationImage Processing, Computer-AssistedModels, MolecularProteinsX-Ray DiffractionJournal ArticleResearch Support, Non-U.S. Gov't

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Luigi Di Costanzo, Federico Forneris, Silvano Geremia, Lucio Randaccio. 2003-07-23. Phasing protein structures using the group-subgroup relation.. https://doi.org/10.1107/s0907444903012538

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