Crystal Form I (crystal + form_i)

Distribution by Scientific Domains


Selected Abstracts


Structural studies of MIP synthase

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 3 2000
Adam J. Stein
The conversion of glucose 6-phosphate to 1- l - myo -inositol 1-şphosphate (MIP) by 1- l - myo -inositol 1-phosphate synthase (MIP synthase) is the first committed and rate-limiting step in the de novo biosynthesis of inositol in all eukaryotes. The importance of inositol-containing molecules both as membrane components and as critical second messenger signal-transduction species make the function and regulation of this enzyme important for a host of biologically important cellular functions including proliferation, neurostimulation, secretion and contraction. MIP synthase has been overexpressed in Esherichia coli and purified to homogeneity by chromatographic methods. Two crystal forms of MIP synthase were obtained by the hanging-drop vapor-diffusion method. Native data sets for both crystal forms were collected in-house on a Rigaku R-AXIS IIC imaging-plate detector. Crystal form I belongs to space group C2, with unit-cell parameters a = 153.0, b = 96.6, c = 122.6,┼, , = 126.4░, and diffracts to 2.5,┼ resolution. Crystal form II belongs to space group P21, with unit-cell parameters a = 94.5, b = 186.2, c = 86.5,┼, , = 110.5░, and diffracts to 2.9,┼ resolution. [source]


Crystallization and preliminary crystallographic analysis of the bacterial capsule assembly-regulating tyrosine phosphatases Wzb of Escherichia coli and Cps4B of Streptococcus pneumoniae

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 8 2009
Hexian Huang
Bacterial tyrosine kinases and their cognate phosphatases are key players in the regulation of capsule assembly and thus are important virulence determinants of these bacteria. Examples of the kinase/phosphatase pairing are found in Gram-negative bacteria such as Escherichia coli (Wzc and Wzb) and in Gram-positive bacteria such as Streptococcus pneumoniae (CpsCD and CpsB). Although Wzb and Cps4B are both predicted to dephosphorylate the C-terminal tyrosine cluster of their cognate tyrosine kinase, they appear on the basis of protein sequence to belong to quite different enzyme classes. Recombinant purified proteins Cps4B of S. pneumoniae TIGR4 and Wzb of E. coli K-30 have been crystallized. Wzb crystals belonged to space-group family P3x21 and diffracted to 2.7,┼ resolution. Crystal form I of Cps4B belonged to space-group family P4x212 and diffracted to 2.8,┼ resolution; crystal form II belonged to space group P212121 and diffracted to 1.9,┼ resolution. [source]


Crystallization and preliminary X-ray diffraction study of a cell-wall invertase from Arabidopsis thaliana

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 8 2005
Maureen Verhaest
Cell-wall invertase 1 (AtcwINV1), a plant protein from Arabidopsis thaliana which is involved in the breakdown of sucrose, has been crystallized in two different crystal forms. Crystal form I grows in space group P31 or P32, whereas crystal form II grows in space group C2221. Data sets were collected for crystal forms I and II to resolution limits of 2.40 and 2.15,┼, respectively. [source]


Purification, crystallization, X-ray diffraction analysis and phasing of a Fab fragment of monoclonal neuroantibody ,D11 against nerve growth factor

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2004
Sonia Covaceuszach
The rat monoclonal neuroantibody ,D11 is a potent antagonist that prevents the binding of nerve growth factor (NGF) to its tyrosine kinase A receptor (TrkA) in a variety of systems, most notably in two in vivo systems linked to crucial pathological states, such as Alzheimer's disease and HIV infection. To provide further insights into the mechanism of action of this potentially therapeutic monoclonal antibody, structural studies of the antigen-binding fragment (Fab) of ,D11 were performed. ,D11 IgG2a immunoglobulin was obtained from hybridomas by in vitro tissue culture. The ,D11 Fab crystallizes in two crystal forms. Form I belongs to space group P1, with unit-cell parameters a = 42.7, b = 50.6, c = 102.7,┼, , = 82.0, , = 89.1, , = 86.0░. With two molecules in the asymmetric unit, VM is 2.3,┼3,Da,1 and the solvent content is 46%. A complete data set has been collected at 2.7,┼ resolution on beamline XRD-1 (ELETTRA, Trieste, Italy). Form II belongs to space group C2, with unit-cell parameters a = 114.8, b = 69.4, c = 64.10,┼, , = 117.0░. With one molecule in the asymmetric unit, VM is 2.4,┼3,Da,1 and the solvent content is 48%. A complete data set has been collected at 1.7,┼ resolution on beamline ID14-1 (ESRF, Grenoble, France). Phasing was successfully performed by Patterson search techniques and refinement of the structures is currently under way. Crystal forms I and II display a close-packing pattern. [source]


Purification, crystallization and initial X-ray diffraction study of human REV7 in complex with a REV3 fragment

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 12 2009
Kodai Hara
REV7 is involved in various cellular functions including DNA replication, signal transduction and cell-cycle regulation. In DNA replication, REV7 interacts with REV3 and forms DNA polymerase ,, which plays a central role in error-prone DNA synthesis. REV3 is a catalytic subunit and its activity is stimulated by REV7. To clarify the structural basis of the interaction between REV7 and REV3, human REV7 was crystallized in complex with a REV3 fragment. Two crystal forms were obtained. Crystal forms I and II belonged to space groups P21, with unit-cell parameters a = 43.8, b = 50.0, c = 107.3,┼, , = 96.9░, and P41212 or P43212, with unit-cell parameters a = b = 76.6, c = 118.4,┼, respectively. [source]


Crystallographic study of G178S mutant of human proliferating cell nuclear antigen

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2008
Asami Hishiki
Proliferating cell nuclear antigen (PCNA) is an evolutionarily conserved protein that forms a ring-shaped homotrimer that functions as a sliding clamp for DNA replication. The rev6-1 mutation of Saccharomyces cerevisiae, which inactivates both translesion DNA synthesis and damage-avoidance pathways while having little effect on normal cell growth, has a G178S substitution in the PCNA protein. Human PCNA protein carrying the G178S substitution was crystallized. Two crystal forms were obtained under similar conditions. Crystal forms I and II belong to space groups P21, with unit-cell parameters a = 84.1, b = 130.2, c = 97.8,┼, , = 113.4░, and P212121, with unit-cell parameters a = 68.1, b = 100.2, c = 131.2,┼, respectively. Structural analyses by molecular replacement are now in progress. [source]


Crystal structure reveals two alternative conformations in the active site of ribonuclease Sa2

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2004
Jozef
Three different strains of Streptomyces aureofaciens produce the homologous ribonucleases Sa, Sa2 and Sa3. The crystal structures of ribonuclease Sa (RNase Sa) and its complexes with mononucleotides have previously been reported at high resolution. Here, the structures of two crystal forms (I and II) of ribonuclease Sa2 (RNase Sa2) are presented at 1.8 and 1.5 ┼ resolution. The structures were determined by molecular replacement using the coordinates of RNase Sa as a search model and were refined to R factors of 17.5 and 15.0% and Rfree factors of 21.8 and 17.2%, respectively. The asymmetric unit of crystal form I contains three enzyme molecules, two of which have similar structures to those seen for ribonuclease Sa, with Tyr87 at the bottom of their active sites. In the third molecule, Tyr87 has moved substantially: the CA atom moves almost 5,┼ and the OH of the side chain moves 10,┼, inserting itself into the active site of a neighbouring molecule at a similar position to that observed for the nucleotide base in RNase Sa complexes. The asymmetric unit of crystal form II contains two Sa2 molecules, both of which are similar to the usual Sa structures. In one molecule, two main-chain conformations were modelled in the ,-helix. Finally, a brief comparison is made between the conformations of the Sa2 molecules and those of 34 independent molecules taken from 20 structures of ribonuclease Sa and two independent molecules taken from two structures of ribonuclease Sa3 in various crystal forms. [source]


Crystallization and preliminary X-ray diffraction study of a cell-wall invertase from Arabidopsis thaliana

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 8 2005
Maureen Verhaest
Cell-wall invertase 1 (AtcwINV1), a plant protein from Arabidopsis thaliana which is involved in the breakdown of sucrose, has been crystallized in two different crystal forms. Crystal form I grows in space group P31 or P32, whereas crystal form II grows in space group C2221. Data sets were collected for crystal forms I and II to resolution limits of 2.40 and 2.15,┼, respectively. [source]