Modulation of activity by Arg407: structure of a fungal α-1,2-mannosidase in complex with a substrate analogue

The structure of P. citrinum α-1,2-mannosidase has been determined at 1.95 Å resolution in complex with methyl-α-D-lyxopyranosyl-(1′,2)-α-D-mannopyranoside.

Application of maximum-entropy maps in the accurate refinement of a putative acylphosphatase using 1.3 Å X-ray diffraction data

An accurate structural refinement using the maximum-entropy method (MEM) is reported. The reliability factor R_free in the SHELX refinement was reduced from 18% to 10% by model building based on MEM charge densities.

Three-dimensional structures of L-asparaginase from Erwinia carotovora complexed with aspartate and glutamate

L-Asparaginase from Er. carotovora belongs to the family of bacterial amidohydrolases and catalyzes the conversion of L-asparagine to aspartic acid and ammonia and, to a lesser extent, the formation of L-glutamic acid from L-glutamine. The highly homologous L-asparaginases from E. coli and Er. chrysanthemi are widely used as effective anti-leukaemia drugs. Like the majority of L-asparaginases, ErcA also reveals antitumour activity, but differs from EcA and ErchA in antigenic specificity. Therefore, ErcA is of special interest as a potential therapeutic agent and as an enzyme suitable for drug development.

Metals in proteins: correlation between the metal-ion type, coordination number and the amino-acid residues involved in the coordination

A study of the specificities of divalent metal cation-binding sites in proteins with known three-dimensional structure is presented.

Differential specific radiation damage in the Cu^II-bound and Pd^II-bound forms of an α-helical foldamer: a case study of crystallographic phasing by RIP and SAD

Radiation-damage-induced phasing of Pd^II-bound and Cu^II-bound complexes of an 18-residue peptide with two disulfide bonds derived from the neurotoxin apamin rested on the differential susceptibility of radiation-sensitive groups in non-isomorphous lattices.

Structure of human monocyte chemoattractant protein 4 (MCP-4/CCL13)

The crystal structure of human monocyte chemoattractant protein 4 (MCP-4), a member of the CC chemokine family, has been determined at 1.70 Å resolution.

Structure of human argininosuccinate synthetase

The first crystal structure of human argininosuccinate synthetase is presented and is compared with its bacterial counterparts.

Glycerol concentrations required for the successful vitrification of cocktail conditions in a high-throughput crystallization screen

The glycerol concentrations necessary to vitrify 1536 high-throughput crystallization-screening cocktails have been determined in order to aid rational prioritization of crystallization leads observed in these cocktails. The concentrations were made by dilution rather than by the replacement of water with glycerol. They therefore serve as a worst-case scenario.

Critical importance of loop conformation to avidin-enhanced hydrolysis of an active biotin ester

Combined mutagenesis and X-ray analysis have been used to attempt to understand the diametric difference in the biotin-binding properties of avidin and streptavidin.

Crystal packing of plant-type L-asparaginase from Escherichia coli

Several crystal forms of E. coli asparaginase/isoaspartyl peptidase (EcAIII) can be obtained under essentially the same crystallization conditions. They all have P2₁2₁2₁ symmetry with similar unit-cell parameters, but show non-isomorphous crystal packing.

The structure of a redundant enzyme: a second isoform of aspartate β-semi­aldehyde de­hydrogenase in Vibrio cholerae

The structure of a second form of aspartate semialdehyde dehydrogenase from V. cholerae has been determined from crystals grow through optimization of the starting buffer conditions. The similarities and differences between isoforms are discussed from both a structural and a functional perspective.

Structures of D-amino-acid amidase complexed with L-phenylalanine and with L-phenylalanine amide: insight into the D-stereospecificity of D-amino-acid amidase from Ochrobactrum anthropi SV3

The crystal structures of D-amino acid amidase complexed with L-phenylalanine and with L-phenylalanine amide reveal three factors related to its D-stereospecificity.

A forward-looking suggestion for resolving the stereochemical restraints debate: ideal geometry functions

A suggestion is put forward concerning the stereochemical restraints debate.