issue contents
November 2007 issue
Cover illustration: Pyruvate oxidase from Aerococcus viridans [Juan et al. (2007), Acta Cryst. F63, 900-907].
protein structure communications
The crystal structures of pyruvate oxidase from A. viridans in complex with flavin adenine dinucleotide, thiamine diphosphate and the reaction intermediate 2-acetyl-thiamine diphosphate reveal details of substrate recognition and catalysis.
The structure of S. aureus MenB, an enzyme in the biosynthetic pathway to vitamin K2, has been determined and compared with the enzyme derived from another important pathogen, M. tuberculosis.
PDB reference: MenB–acetoacetyl-CoA complex, 2uzf, r2uzfsf
The structure of the winged helix–turn–helix DNA-binding domain of AhrC has been determined at 1.0 Å resolution. The largely hydrophobic β-wing shows high B factors and may mediate the dimer interface in operator complexes.
PDB reference: NAhrC, 2p5k, r2p5ksf
The crystal structure of the C-terminal domain hexameric core of AhrC, with bound corepressor (L-arginine), has been solved at 1.95 Å resolution. Binding of L-arginine results in a rotation between the two trimers of the hexamer, leading to the activation of the DNA-binding state.
PDB reference: holo-CAhrC, 2p5m, r2p5msf
structural genomics communications
The X-ray crystal structure of the GTPase YjeQ from S. typhimurium is presented and compared with those of orthologues from T. maritima and B. subtilis.
PDB reference: ribosomal interacting GTPase YjeQ, 2rcn, r2rcnsf
crystallization communications
Crystallization and preliminary crystallographic studies of Schizolobium parahyba chymotrypsin inhibitor (SPCI) at 1.8 Å resolution.
The β-xylosidase was crystallized using PEG 6000 as precipitant. 5% PEG 6000 yielded bipyramid-shaped tetragonal crystals diffracting to 1.55 Å resolution, and 13% PEG 6000 gave rectangular monoclinic crystals diffracting to 1.80 Å resolution.
The C-terminal portion of the arginine repressor protein from M. tuberculosis H37Rv has been crystallized. The complete transcriptional factor regulates arginine biosynthesis by binding operator DNA when arginine is bound at the C-terminal domain.
The Met244Ala variant of the H. marismortui KatG enzyme was expressed in haloarchaeal host cells and purified to homogeneity. The variant was crystallized using the hanging-drop vapour-diffusion method with ammonium sulfate and NaCl as precipitants. The reddish-brown rod-shaped crystals obtained belong to the monoclinic space group C2, with unit-cell parameters a = 315.24, b = 81.04, c = 74.77 Å, β = 99.81°.
PHBH from Corynebacterium glutamicum was crystallized using the hanging-drop vapour-diffusion method in the presence of NaH2PO4 and K2HPO4 as precipitants. X-ray diffraction data were collected to a maximum resolution of 2.5 Å on a synchrotron beamline.
Octaketide synthase from A. arborescens has been overexpressed in E. coli, purified and crystallized. Diffraction data have been collected to 2.6 Å.
A truncated variant of human ribosomal protien L10 was prepared and crystallized. Diffraction data were collected to 2.5 Å resolution.
Free-interface diffusion crystallization chips were used to identify crystallization conditions for S. aureus DsbA, representing the first Gram-positive DsbA to be crystallized. Native and selenomethionine-derivative crystals diffracted to 2.1 and 2.4 Å resolution, respectively.
The cloning, purification and crystallization of YnaF from S. typhimurium are reported along with preliminary X-ray crystallographic studies.
Chloride intracellular channel 2 (CLIC2) belongs to a family of intracellular chloride-channel proteins that can exist in a soluble form. The expression, purification and crystallization in two different crystal forms of human CLIC2 is reported.
A putative member of the Lrp/AsnC family of transcriptional regulators, ST1022 from S. tokodaii strain 7, has been purified and crystallized in the absence and presence of the effector L-glutamine. A molecular-replacement solution was found using the FL11 transcriptional regulator from Pyrococcus sp. OT3 as a model and structural refinement is under way.
Human galectin-1 has been cloned, expressed in E. coli, purified and crystallized in the presence of both lactose (ligand) and β-mercaptoethanol under six different conditions. The X-ray diffraction data obtained have enabled the assignment of unit-cell parameters for two novel crystal forms of human galectin-1.
Protein engineering dramatically enhances the quality of crystals of a Ca2+-dependent membrane-binding protein.
The crystallization of the brazil nut allergen Ber e 2 is reported.
The flavin-dependent monooxygenase RebC has been crystallized by the hanging-drop vapour-diffusion method and initial X-ray diffraction analysis has been completed.
A psychrophilic malate dehydrogenase from the novel Antarctic bacterium F. frigidimaris KUC-1 was crystallized using the hanging-drop vapour-diffusion method. The crystals contained one tetrameric molecule per asymmetric unit. The best crystal diffracted to 1.8 Å resolution.
The purification, crystallization and preliminary X-ray diffraction data of the protein struthiocalcin 1 isolated from ostrich eggshell are reported.
Preliminary X-ray diffraction studies of apo maize aldose reductase at 2.0 Å resolution are reported.