Crystallography Research Today is a free monthly online journal that collates and summarizes the latest research about Crystallography, including details on x-ray crystals, techniques, analyses, structures.

Analysis of solvent content and oligomeric states in protein crystals--does symmetry matter?

Chruszcz M, Potrzebowski W, Zimmerman MD, Grabowski M, Zheng H, Lasota P, Minor W

Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22908, USA.

A nonredundant set of 9081 protein crystal structures in the Protein Data Bank was used to examine the solvent content, the number of polypeptide chains, and the oligomeric states of proteins in crystals as a function of crystal symmetry (as classified by crystal systems and space groups). It was found that there is a correlation between solvent content and crystal symmetry. Surprisingly, proteins crystallizing in lower symmetry systems have lower solvent content compared to those crystallizing in higher symmetry systems. Nevertheless, there is no universal correlation between solvent content and preferences of macromolecules to crystallize in certain space groups. Crystal symmetry as a function of oligomeric state was examined, where trimers, tetramers, and hexamers were found to prefer to crystallize in systems where the oligomer symmetry could be incorporated in the crystal symmetry. Our analysis also shows that the frequency distribution within the enantiomorphous pairs of space groups does not differ significantly, in contrast to previous reports.

Published 24 March 2008 in Protein Sci, 17(4): 623-32.
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Articles on Crystallography published 21 March 2008:

Small-angle X-ray scattering reveals the N-terminal domain organization of cardiac myosin binding protein C.   J Mol Biol, 377(4): 1186-99.

Myosin binding protein C (MyBP-C) is a multidomain accessory protein of striated muscle sarcomeres. Three domains at the N-terminus of MyBP-C (C1-m-C2) play a crucial role in maintaining and modulating actomyosin interactions. The cardiac isoform has an additional N-terminal domain (C0) that is postulated to provide a greater level of regulatory control in cardiac muscle. We have used small-angle X-ray scattering, ab initio shape restoration, and rigid-body modeling to determine the average ... [Abstract] [Full-text]

Articles on Crystallography published 13 March 2008:

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Articles on Crystallography published 3 March 2008:

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In crystals of complexes of thermine and d(CGCGCG)2 molecules grown at 4, 10, and 20 degrees C, the numbers of thermine molecules connected to the DNA molecule were dependent on the temperature of the crystallization. Two molecules of thermine and one Mg2+ ion were connected to DNA molecule when thermine and d(CGCGCG)2 were co-crystallized at 4 and at 20 degrees C. When an increased concentration of magnesium and thermine molecules were co-crystallized with d(CGCGCG)2 molecules at 10 degrees C, ... [Abstract] [Full-text]

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Site-specifically modified 2'-methylseleno RNA represents a valuable derivative for phasing of X-ray crystallographic data. Several successful applications in three-dimensional structure determination of nucleic acids, such as the Diels-Alder ribozyme, have relied on this modification. Here, we introduce synthetic routes to 2'-methylseleno phosphoramidite building blocks of all four standard nucleosides, adenosine, cytidine, guanosine and uridine, that are tailored for ... [Abstract] [Full-text]

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Articles on Crystallography published 24 January 2008:

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