Direct inter-subdomain interactions switch between the closed and open forms of the Hsp70 nucleotide-binding domain in the nucleotide-free state

In this study, the crystal structures of the human Hsp70 nucleotide-binding domain (NBD) fragment were determined in the nucleotide-free state and in complex with adenosine 5′-­(β,γ-imido)­triphosphate (AMPPNP).

Structure of the unbound form of HIV-1 subtype A protease: comparison with unbound forms of proteases from other HIV subtypes

The crystal structure of the unbound form of HIV-1 subtype A protease has been determined to 1.7 Å resolution. A detailed structural analysis and comparison of the unbound subtype A, B and C protease structures is presented. The results showed that although no inhibitor is present in the active site, the subtype A protease has flaps in the closed position.

Introduction of a leucine half-zipper engenders multiple high-quality crystals of a recalcitrant tRNA synthetase

E. coli alanyl-tRNA synthetase is recalcitrant to crystallization. A group of leucine substitutions has transformed the protein.

Coiled-coil conformation of a pentamidine–DNA complex

The oligonucleotide d(ATATATATAT) has been crystallized as a coiled coil in the presence of pentamidine. The drug sits in the minor groove of the duplex, but shows a new form of interaction with DNA as a cross-linking agent. The duplex contains both Watson–Crick and Hoogsteen base pairs.

pH-dependent structural changes in haemoglobin component V from the midge larva Propsilocerus akamusi (Orthocladiinae, Diptera)

The crystal structure of midge larval haemoglobin was determined at five different pH conditions. Comparison of these structures indicated that pH changes result in a swinging movement of the distal Arg residue and a partial shift of the F-helix C-terminus followed by haem tilting in this insect haemoglobin.

Rapid model building of α-helices in electron-density maps

A method for rapid model building of α-helices at moderate resolution is presented.

Rapid model building of β-sheets in electron-density maps

A method for rapid model building of β-sheets at moderate resolution is presented.

Rapid chain tracing of polypeptide backbones in electron-density maps

A method for rapid chain tracing of polypeptide backbones at moderate resolution is presented.

Structural insights into the assembly of the human and archaeal signal recognition particles

The structures of the human and a crenarchaeal SRP19–SRP RNA complex reveal general features of SRP S-domain organization and allow an update of the SRP-assembly paradigm.

Getting the best out of long-wavelength X-rays: de novo chlorine/sulfur SAD phasing of a structural protein from ATV

The solution of a structural protein from the Acidianus two-tailed virus using long-wavelength SAD phasing suggests a systematic approach for the solution of protein crystal structures by taking advantage of the anomalous signal of serendipitously associated chloride ions from the solvent.

Structure determination using poorly diffracting membrane-protein crystals: the H⁺-ATPase and Na⁺,K⁺-ATPase case history

Procedures for heavy-atom site identification by molecular replacement at low resolution and for density modification by multi-crystal averaging using quasi-isomorphous diffraction data are presented. The procedures are based on the case history from the structure determination of H⁺-ATPase and Na⁺, K⁺-ATPase and have been successfully applied to the transporter Mhp1 to reveal general applicability.

Accommodation of structural rearrangements in the huntingtin-interacting protein 1 coiled-coil domain

Variable packing interaction related to the conformational flexibility within the huntingtin-interacting protein 1 coiled coil domain.

Deleting two C-terminal α-helices is effective to crystallize the bacterial ABC transporter Escherichia coli MsbA complexed with AMP-PNP

Deleting two C-terminal α-helices of the MsbA molecule from E. coli improved its crystallizability and generated new crystal forms of the complex with adenosine 5′-(β,γ-imido)triphosphate that had an outward-facing conformation.