The properties of the mesoscopic protein-rich clusters, within which protein crystal nuclei form, are reviewed. The cluster populations occupy from 10−7 to 10−3 of the solution volume; the cluster radii are of order 100 nm; the clusters exist owing to the formation of transient oligomers that, for some proteins, may be due to conformational flexibility.
New crystallization conditions for the catalytic domain of human ubiquitin specific protease 7 (USP7CD) were found that produced crystals in space group C2 with one molecule in the asymmetric unit which is an advantage over previous crystallization conditions of USP7CD which produced crystals in space group P21 with two molecules in the asymmetric unit. Comparison of the refined structure of USP7CD in space group C2 with that of P21 suggests that conformational rearrangement of blocking loop residues 410–419 must occur in order for ubiquitin to bind and that the catalytic triad and switching loop region are in the same catalytically unproductive conformations as in the P21 structure in the absence of ubiquitin.
A co-crystal structure of human farnesyl pyrophosphate synthase in complex with an aminopyridine bisphosphonate, YS0470, and two molecules of inorganic phosphate has been determined. The identity of the phosphate ligands was confirmed by anomalous diffraction data.
The structure of a new crystal form of IgE-Fc in complex with its B-cell receptor CD23 has been determined. The structure reveals that there is conformational variability at the interface in both IgE-Fc and CD23.
Immunity protein TsiV3 from Vibrio cholera has been expressed, purified and crystallized. The crystal belonged to space group P212121, with unit-cell parameters a = 73.3, b = 78.12, c = 106.18 Å and diffract to 2.55 Å resolution.
A truncated form of AmbB from Pseudomonas aeruginosa that contains a phosphopantetheine binding (PB) domain and a condensation domain has been crystallized and diffraction data were collected to 2.45 Å resolution.
The C-terminal kinase domain of TLK2 (a human tousled-like kinase) has been cloned and overexpressed in Escherichia coli followed by purification to homogeneity. Crystallization experiments in the presence of ATP-γ-S yielded crystals suitable for X-ray diffraction analysis belonging to two different space groups: tetragonal I4122 and cubic P213.
The soluble extracellular fragment of the interleukin-3 alpha receptor (IL3Rα) was complexed with the Fab fragment of antibody CSL362 and crystals of the IL3Rα–CSL362 complex were obtained. These crystals belonged to the monoclinic P21 space group and diffracted to 2.8 Å resolution at the Australian Synchrotron.
The 33 kDa haemagglutinin subcomponent of the botulinum toxin complex of the unique strain of serotype C Clostridium botulinum was crystallized and X-ray diffraction data were collected to 2.2 Å resolution.
In order to understand the molecular basis of action of the Alzheimer's disease passive immunotherapy candidate bapineuzumab, the Fab fragment of this antibody was crystallized in complexes with Aβ peptides. The best crystals diffracted to a resolution of 2.0 Å (Aβ residues 1–8) and 2.2 Å (Aβ residues 1–28).