Ligand binding at the transthyretin dimer–dimer interface: structure of the transthyretin–T4Ac complex at 2.2 Å resolution

The crystal structure of the human transthyretin–tetraiodothyroacetic acid complex was determined. The ligand is in an unusual position, penetrating the dimer–dimer interface and interacting with three TTR monomers simultaneously.

The structure of Cryptococcus neoformans thymidylate synthase suggests strategies for using target dynamics for species-specific inhibition

The ternary complex structures of C. neoformans TS and human TS are highly conserved. A 1,8-naphthalein derivative that selectively inhibits C. neoformans and E. coli TSs over human TS binds to an open conformation of E. coli TS. Disorder of the inhibitor-binding site in the human apoenzyme may explain the inhibitor specificity.

Conserved solvent and side-chain interactions in the 1.35 Å structure of the Kelch domain of Keap1

Use of 1.35 Å SAD data for de novo structure determination of the Kelch domain and for refinement at atomic resolution is described.

Structure of the hypothetical Mycoplasma protein MPN555 suggests a chaperone function

The crystal structure of a hypothetical protein (MPN555) from M. pneumoniae revealed a trilobal molecule with at least one central binding pocket or channel. The molecule has structural homology with two bacterial chaperone proteins, which suggests a similar chaperone function for MPN555.

Structures of two minor-groove-binding quinolinium quaternary salts complexed with d(CGCGAATTCGCG)₂ at 1.6 and 1.8 Å resolution

The high-resolution X-ray crystal structures of two anticancer minor-groove-binding quinolinium quaternary salts complexed with the dodecamer d(CGCGAATTCGCG)₂ are reported.

Automated crystallographic ligand building using the medial axis transform of an electron-density isosurface

Use of the medial axis for automated crystallographic model building is described.

Three-dimensional structure determination of proteins related to human health in their functional context at The Israel Structural Proteomics Center (ISPC)

The work of the Israel Structural Proteomics Center (ISPC) to determine the structures of proteins related to human health in their functional context is described.

Absolute configuration of the hydroxyfarnesylethyl group of haem A, determined by X-ray structural analysis of bovine heart cytochrome c oxidase using methods applicable at 2.8 Å resolution

The absolute configuration of haem A, the prosthetic group of cytochrome c oxidase, was determined to be S by analyzing bond angles.

A flexible and economical medium-throughput strategy for protein production and crystallization

A medium-throughput strategy has been developed for academic structural biology that meets the twin goals of research output and graduate-student development. The platform incorporates Gateway cloning and 96-well methods for solubility screening and crystallization.

Crystallographic analysis of the NNA7 Fab and proposal for the mode of human blood-group recognition

The NNA7 Fab antibody fragment recognizes the human N blood-group antigen, whereas the NNA7-G91S mutant exhibits reduced antigen binding. To provide insight into how these Fab fragments recognize this clinically relevant glycopeptide antigen, the crystal structures of both Fab fragments were solved. The results provide a model for peptide and sugar recognition based upon crystallographic contacts, as well as a bound 2-(N-morpholino)ethanesulfonic acid (MES) molecule trapped in the antigen-combining site.

Structure of free fumarase C from Escherichia coli

The crystal structure of fumarase C has been solved in the absence of inhibitors and substrate analogues. This novel crystal structure reports a pH-sensitive shift at the allosteric B site and preservation of the architecture surrounding the conserved active-site water.

Structural studies on recombinant T = 3 capsids of Sesbania mosaic virus coat protein mutants

Purified Sesbania mosaic virus coat-protein particles have been crystallized and X-ray crystal structures of their mutant capsids have been determined.

Structure of a mutant T = 1 capsid of Sesbania mosaic virus: role of water molecules in capsid architecture and integrity

The role of water molecules in the Sesbania mosaic virus structure has been analyzed.

High-resolution neutron protein crystallography with radically small crystal volumes: application of perdeuteration to human aldose reductase

Perdeuterated human aldose reductase neutron diffraction data at 2.2 Å resolution was collected from a 0.15 mm³ crystal. Deuterium atoms were clearly seen in the neutron-scattering density map.

Mutation of surface residues to promote crystallization of activated factor XI as a complex with benzamidine: an essential step for the iterative structure-based design of factor XI inhibitors

The crystallizability of coagulation factor XI has been improved by surface-residue mutation, generating a quadruple mutant that crystallizes easily in the presence of benzamidine and has facilitated the iterative process of structure-based design of factor XI selective inhibitors.

Towards rationalization of crystallization screening for small- to medium-sized academic laboratories: the PACT/JCSG+ strategy

A strategy for crystallization screening using nanolitre drops and a combination of a sparse-matrix screen (JCSG+) and a novel systematic screen (PACT) is presented and discussed.

Notes of a protein crystallographer: my nights with ACTOR

A historical perspective of the steps leading to the current robot technology available for crystal mounting and data collection is presented. The implications for the future of the field are briefly discussed.

Protein-Ligand Interactions: Methods and Applications