Detection and correction of underassigned rotational symmetry prior to structure deposition

An X-ray structural model can be reassigned to a higher symmetry space group using the presented framework if its noncrystallographic symmetry operators are close to being exact crystallographic relationships. About 2% of structures in the Protein Data Bank can be reclassified in this way.

Macromolecular crystal data phased by negative-stained electron-microscopy reconstructions

The crystal structures of two medium-size proteins (type II dehydroquinases, ∼190 kDa) have been solved using a low-resolution reconstruction obtained by negative-staining EM, a technique that is of wider applicability than cryo-EM.

Structure of the Methanothermobacter thermautotrophicus exosome RNase PH ring

The crystal structure of the RNase PH ring from the exosome of M. thermautotrophicus is described at 2.65 Å resolution.

Structure of dehaloperoxidase B at 1.58 Å resolution and structural characterization of the AB dimer from Amphitrite ornata

The crystal structure of dehaloperoxidase (DHP) isoenzyme B from the terebellid polychaete A. ornata, which exhibits both hemoglobin and peroxidase functions, has been determined at 1.58 Å resolution.

Polymorphism of microcrystalline urate oxidase from Aspergillus flavus

A rich phase diagram of urate oxidase, a protein of high pharmaceutical importance, associated with enhanced polymorphism is revealed.

Structural analysis of mycobacterial branched-chain aminotransferase: implications for inhibitor design

Structural and inhibition studies of mycobacterial branched-chain aminotransferases were performed with implications for drug design.

Unambiguous determination of H-atom positions: comparing results from neutron and high-resolution X-ray crystallography

Comparative analysis of the prominence of D atoms in neutron and X-ray density maps shows that 1.65 Å resolution neutron diffraction analysis is eightfold more powerful for determining the positions of D atoms than 1.1 Å resolution X-ray diffraction.

Acoustic matrix microseeding: improving protein crystal growth with minimal chemical bias

Acoustic liquid handling is employed to deliver crystal seeds in single-digit nanolitre volumes to induce crystallization in sparse-matrix screens while minimizing chemical bias from buffer components in the seed suspension.

Structures of the PKC-ι kinase domain in its ATP-bound and apo forms reveal defined structures of residues 533–551 in the C-terminal tail and their roles in ATP binding

Structures of PKC-ι kinase domains have been determined in both apo and ATP-bound forms. The structure of residues 533–551 and the residues around the turn motif in the C-terminal tail are newly defined and help to reveal their roles in ATP binding.

Structure of D-tyrosyl-tRNA^Tyr de­acylase using home-source Cu Kα and moderate-quality iodide-SAD data: structural polymorphism and HEPES-bound enzyme states

Structure solution using iodide-SAD.

Structure and substrate docking of a hy­droxy(phenyl)pyruvate reductase from the higher plant Coleus blumei Benth.

The crystal structures of the apo and holo forms of NADPH-dependent hydroxy(phenyl)pyruvate reductase from C. blumei are reported.

Application of protein engineering to enhance crystallizability and improve crystal properties

This article presents an overview of protein-engineering methods designed to enhance crystallizability and discusses a number of examples of their successful application.

Atomic resolution studies of carbonic anhydrase II

The structure of human carbonic anhydrase II has been solved with a sulfonamide inhibitor at 0.9 Å resolution. Structural variation and flexibility is seen on the surface of the protein and is consistent with the anisotropic ADPs obtained from refinement. Comparison with 13 other atomic resolution carbonic anhydrase structures shows that surface variation exists even in these highly ordered isomorphous crystals.

Structure of a monoclinic polymorph of human carbonic anhydrase II with a doubled a axis

The crystal structure of human carbonic anhydrase II with a doubled a axis from that of the usually observed monoclinic cell has been determined and refined to 1.4 Å resolution. The two molecules comprising the asymmetric unit are related by a noncrystallographic translation of ½ along a, but one of the molecules has two alternate orientations related by a rotation of approximately 2°.

Analysis of multiple crystal forms of Bacillus subtilis BacB suggests a role for a metal ion as a nucleant for crystallization

Bacillus subtilis BacB crystallizes in three crystal forms. The differences in the packing between these crystal forms could be rationalized on the basis of metal ions bound on the protein surface that mediate lattice contacts.

Biomolecular Crystallography: Principles, Practice, and Applications to Structural Biology