Exploring the complex map of insulin polymorphism: a novel crystalline form in the presence of m-cresol

2020 ◽  
Vol 76 (4) ◽  
pp. 366-374 ◽  
Author(s):  
Fotini Karavassili ◽  
Alexandros Valmas ◽  
Maria Dimarogona ◽  
Anastasia E. Giannopoulou ◽  
Stavroula Fili ◽  
...  
Keyword(s):  
Single Crystal ◽  
Crystal Form ◽  
Crystalline Form ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Potential Use

In this study, the first crystal structure of a novel crystal form of human insulin bound to meta-cresol in an acidic environment is reported. The combination of single-crystal and powder X-ray diffraction crystallography led to the detection of a previously unknown monoclinic phase (P21). The structure was identified from the powder patterns and was solved using single-crystal diffraction data at 2.2 Å resolution. The unit-cell parameters at pH 6.1 are a = 47.66, b = 70.36, c = 84.75 Å, β = 105.21°. The structure consists of two insulin hexamers per asymmetric unit. The potential use of this insulin form in microcrystalline drugs is discussed.

Preparation and preliminary X-ray diffraction studies of a new crystal form of L-asparaginase from Escherichia coli

1999 ◽  
Vol 55 (9) ◽  
pp. 1616-1617
Author(s):  
I. Polikarpov ◽  
R. T. de Oliveira ◽  
J. Abrahão-Neto
Keyword(s):  
Escherichia Coli ◽  
Synchrotron Radiation ◽  
Crystal Form ◽  
Asymmetric Unit ◽  
Chemotherapeutic Drug ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Synchrotron Radiation Diffraction

L-Asparaginase is an enzyme which hydrolyzes asparagine to produce aspartic acid and ammonia. It is an effective chemotherapeutic drug, especially in the treatment of acute lymphoblastic leukaemia in children. The enzyme from Escherichia coli was crystallized in a new crystal form with space group C2, unit-cell parameters a = 76.3 (0), b = 134.6 (2), c = 64.8 (7) Å, β = 110.5 (1)° and a dimer in the asymmetric unit. Synchrotron-radiation diffraction data have been collected to 1.95 Å resolution.

X-ray Diffraction Study of the Crystal Structure of the Tl Ternary Chalcogenides Tl2x In2(1−x)Se2, x = 0.2, 0.3,...0.9

1998 ◽  
Vol 54 (4) ◽  
pp. 358-364 ◽  
Author(s):  
K. G. Hatzisymeon ◽  
S. C. Kokkou ◽  
A. N. Anagnostopoulos ◽  
P. I. Rentzeperis
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Rietveld Method ◽  
Direct Methods ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Volume Decrease

A series of thallium ternary chalcogenides with the composition Tl2x In2(1−x)Se2, x = 0.2, 0.3,...0.9, have been studied by X-ray powder and, for some of them, single-crystal diffraction. They are tetragonal, space group I4/mcm, Z = 4, and isostructural with the binary semiconductor TlSe. Their crystal structures have been solved by direct methods and refined by the Rietveld method to a precision which is satisfactorily comparable to single-crystal results. As x is changed from x = 0.2 to x = 0.9 the unit-cell parameters and volume decrease or increase following Kurnakov's law, which is valid for solid solutions. Refined positional parameters of Se, In—Se and Tl—Se bond lengths vary with x also according to the same law. The distribution of In and Tl cations in 4(a) and 4(b) sites depends on the stoichiometry x and the crystals are composed of [In3+Se2]_{\infty}^- chains along the c axis in which InSe4 tetrahedra share edges; the chains are interconnected with Tl+(In+) ions.

Refinement of the crystal structure of sieleckiite and revision of its symmetry

2017 ◽  
Vol 81 (4) ◽  
pp. 917-922
Author(s):  
Peter Elliott
Keyword(s):  
Crystal Structure ◽  
Synchrotron Radiation ◽  
Single Crystal ◽  
Diffraction Data ◽  
X Ray Diffraction ◽  
Aluminium Phosphate ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Phosphate Mineral

AbstractThe crystal structure of the copper aluminium phosphate mineral sieleckiite, Cu3Al4(PO4)2 (OH)12·2H2O, from the Mt Oxide copper mine, Queensland, Australia was solved from single-crystal X-ray diffraction data utilizing synchrotron radiation. Sieleckiite has monoclinic rather than triclinic symmetry as previously reported and is space group C2/m with unit-cell parameters a = 11.711(2), b = 6.9233(14), c = 9.828(2) Å, β = 92.88(3)°, V = 795.8(3) Å3and Z = 2. The crystal structure, which has been refined to R1 = 0.0456 on the basis of 1186 unique reflections with Fo > 4σF, is a framework of corner-, edge- and face- sharing Cu and Al octahedra and PO4 tetrahedra.

scholarly journals Crystallization and X-ray diffraction analysis of native and selenomethionine-substituted PhyH-DI fromBacillussp. HJB17

2017 ◽  
Vol 73 (11) ◽  
pp. 607-611
Author(s):  
Fang Lu ◽  
Bei Zhang ◽  
Yong Liu ◽  
Ying Song ◽  
Gangxing Guo ◽  
...  
Keyword(s):  
Unit Cell ◽  
Diffusion Method ◽  
Data Sets ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Solvent Content ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

Phytases are phosphatases that hydrolyze phytates to less phosphorylatedmyo-inositol derivatives and inorganic phosphate. β-Propeller phytases, which are very diverse phytases with improved thermostability that are active at neutral and alkaline pH and have absolute substrate specificity, are ideal substitutes for other commercial phytases. PhyH-DI, a β-propeller phytase fromBacillussp. HJB17, was found to act synergistically with other single-domain phytases and can increase their efficiency in the hydrolysis of phytate. Crystals of native and selenomethionine-substituted PhyH-DI were obtained using the vapour-diffusion method in a condition consisting of 0.2 Msodium chloride, 0.1 MTris pH 8.5, 25%(w/v) PEG 3350 at 289 K. X-ray diffraction data were collected to 3.00 and 2.70 Å resolution, respectively, at 100 K. Native PhyH-DI crystals belonged to space groupC121, with unit-cell parametersa = 156.84,b = 45.54,c = 97.64 Å, α = 90.00, β = 125.86, γ = 90.00°. The asymmetric unit contained two molecules of PhyH-DI, with a corresponding Matthews coefficient of 2.17 Å3 Da−1and a solvent content of 43.26%. Crystals of selenomethionine-substituted PhyH-DI belonged to space groupC2221, with unit-cell parametersa = 94.71,b= 97.03,c= 69.16 Å, α = β = γ = 90.00°. The asymmetric unit contained one molecule of the protein, with a corresponding Matthews coefficient of 2.44 Å3 Da−1and a solvent content of 49.64%. Initial phases for PhyH-DI were obtained from SeMet SAD data sets. These data will be useful for further studies of the structure–function relationship of PhyH-DI.

D'ansite-(Mn), Na21Mn2+(SO4)10Cl3 and d'ansite-(Fe), Na21Fe2+(SO4)10Cl3, two new minerals from volcanic fumaroles

2012 ◽  
Vol 76 (7) ◽  
pp. 2773-2783 ◽  
Author(s):  
F. Demartin ◽  
I. Campostrini ◽  
C. Castellano ◽  
C. M. Gramaccioli ◽  
M. Russo
Keyword(s):  
Single Crystal ◽  
Empirical Formula ◽  
Energy Dispersive Spectrometry ◽  
Chemical Analyses ◽  
Crystal Data ◽  
Unit Cell Parameters ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Fossa Crater

AbstractThe new minerals d'ansite-(Mn), Na21Mn2+(SO4)10Cl3, and d'ansite-(Fe), Na21Fe2+(SO4)10Cl3, occur as encrustations in fumaroles at Vesuvius, Naples, Italy and La Fossa crater, Vulcano, Aeolian Islands, Italy, respectively. Both minerals are cubic and crystallize in space group I3d. D'ansite-(Mn) forms colourless translucent tristetrahedral crystals up to 0.2 mm on edge; d'ansite-(Fe) forms aggregates of colourless to white complex isometric crystals of about the same size. Chemical analyses obtained by energy-dispersive spectrometry on an electron microprobe gave the following mean compositions: d'ansite-(Mn), Na2O 39.37, MnO 3.46, MgO 0.13, SO3 49.99, Cl 6.36, O=Cl–1.44, total 97.87 wt.%, corresponding to an empirical formula, on the basis of 43 anions, of Na20.61 (Mn2+0.79Mg0.05)Σ0.84S10.13O40.09Cl2.91; and d'ansite-(Fe), Na2O 39.12, FeO 4.18, MgO 0.12, SO3 49.91, Cl 6.81, O=Cl –1.54, total 98.60 wt.%, corresponding to an empirical formula of Na20.42(Fe2+0.94Mg0.05)Σ0.99S10.08O39.89Cl3.11. The six strongest reflections in the X-ray powder diffraction pattern of d'ansite-(Fe) [listed as dobs(Å) (I) (hkl)] are as follows: 2.807(100)(044), 2.570(37)(235), 1.714(29)(129), 3.384(27)(233), 3.113(26)(134), 2.108(15)(237). The unit-cell parameters obtained from single-crystal data are 15.9291(9) and 15.882(3) Å for d'ansite-(Mn) and d'ansite-(Fe), respectively. The structure of both minerals was refined, using single-crystal diffraction data, to final R parameters of 0.0309 and 0.0336 on reflections with I > 2σ(I). The structure contains three independent Na sites, one of which is partially occupied by Mn2+ or Fe2+, two independent sulfate anions and one chlorine site.

scholarly journals Synthesis, Crystal Structure, and Solubility Analysis of a Famotidine Cocrystal

Crystals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 360 ◽  
Author(s):  
Yan Zhang ◽  
Zhao Yang ◽  
Shuaihua Zhang ◽  
Xingtong Zhou
Keyword(s):  
Crystal Structure ◽  
Malonic Acid ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
H2 Receptor Antagonist ◽  
Single Crystal Diffraction ◽  
Intermolecular Hydrogen Bonds ◽  
X Ray ◽  
Cell Parameters ◽  
Cocrystal Structure

A novel cocrystal of the potent H2 receptor antagonist famotidine (FMT) was synthesized with malonic acid (MAL) to enhance its solubility. The cocrystal structure was characterized by X-ray single crystal diffraction, and the asymmetry unit contains one FMT and one MAL connected via intermolecular hydrogen bonds. The crystal structure is monoclinic with a P21/n space group and unit cell parameters a = 7.0748 (3) Å, b = 26.6502 (9) Å, c = 9.9823 (4) Å, α = 90, β = 104.2228 (12), γ = 90, V = 1824.42 (12) Å3, and Z = 4. The cocrystal had unique thermal, spectroscopic, and powder X-ray diffraction (PXRD) properties that differed from FMT. The solubility of the famotidine-malonic acid cocrystal (FMT-MAL) was 4.2-fold higher than FMT; the FAM-MAL had no change in FMT stability at high temperature, high humidity, or with illumination.

scholarly journals Crystallization and preliminary X-ray diffraction analysis of human DNA primase

2014 ◽  
Vol 70 (2) ◽  
pp. 206-210 ◽  
Author(s):  
Andrey G. Baranovskiy ◽  
Jianyou Gu ◽  
Nigar D. Babayeva ◽  
Vinod B. Agarkar ◽  
Yoshiaki Suwa ◽  
...  
Keyword(s):  
Active Site ◽  
Large Subunit ◽  
Structural Studies ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Human Dna ◽  
Structural Details

Human primase synthesizes RNA primers and transfers them to the active site of Pol α with subsequent extension with dNTPs. Human primase is a heterodimer of two subunits: a small catalytic subunit (p49) and a large subunit (p58). The structural details of the initiation and elongation steps of primer synthesis, as well as primer length counting, are not known. To address these questions, structural studies of human primase were initiated. Two types of crystals were obtained. The best diffracting crystals belonged to space groupP1, with unit-cell parametersa= 86.2,b= 88.9,c= 94.68 Å, α = 93.82, β = 96.57, γ = 111.72°, and contained two heterodimers of full-length p49 and p59 subunits in the asymmetric unit.

Single-crystal X-ray diffraction, EMPA, FTIR and X-ray photoelectron spectroscopy study of narsarsukite from Murun Massif, Russia

2017 ◽  
Vol 81 (2) ◽  
pp. 339-354 ◽  
Author(s):  
E. Schingaro ◽  
E. Mesto ◽  
M. Lacalamita ◽  
F. Scordari ◽  
E. Kaneva ◽  
...  
Keyword(s):  
Single Crystal ◽  
Photoelectron Spectroscopy ◽  
Chemical Study ◽  
Structural Disorder ◽  
Crystal Chemical ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Alkaline Massif

AbstractA crystal chemical study of narsarsukite from the Murun alkaline massif, Russia has been carried out combining single-crystal X-ray diffraction, electron microprobe analyses, micro-Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The narsarsukite single crystals are tetragonal (space group I4/m) with unit-cell parameters: 10.7140(1) ≤ a ≤ 10.7183(2) Å and 7.9478(1) ≤ c ≤ 7.9511(1) Å. The XPS analysis showed that Fe occurs in the mineral as Fe3+, whereas the FTIR spectrum showed that the sample studied is anhydrous. The average crystal chemical formula of the Murun narsarsukite is: Na2.04K0.01(V0.015+Ti0.74Zr0.01Al0.01Fe0.223+Mg0.01)1.00Si4.00(O10.74F0.23OH0.03)11.00. Structural disorder at octahedral and interstitial sites was modelled and also discussed in consideration of the main substitutional mechanism Ti4+ + O2– ↔ Fe3+ + (F–, OH–) active in the structure of the mineral.

scholarly journals Overproduction, crystallization and preliminary X-ray crystallographic analysis ofEscherichia colitRNAN6-threonylcarbamoyladenosine dehydratase

2014 ◽  
Vol 70 (11) ◽  
pp. 1517-1520 ◽  
Author(s):  
Sunmin Kim ◽  
Keon Young Kim ◽  
Jeong Kuk Park ◽  
Byung Il Lee ◽  
Yun-Gon Kim ◽  
...  
Keyword(s):  
Crystallographic Analysis ◽  
X Rays ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
E Coli ◽  
Protein Mass ◽  
Crystal Volume

Escherichia colitRNAN6-threonylcarbamoyladenosine dehydratase (TcdA), previously called CsdL or YgdL, was overproduced and purified fromE. coliand crystallized using polyethylene glycol 3350 as a crystallizing agent. X-ray diffraction data were collected to 2.70 Å resolution under cryoconditions using synchrotron X-rays. The crystals belonged to space groupP21, with unit-cell parametersa= 65.4,b= 96.8,c= 83.3 Å, β = 111.7°. According to the Matthews coefficient, the asymmetric unit may contain up to four subunits of the monomeric protein, with a crystal volume per protein mass (VM) of 2.12 Å3 Da−1and 42.1% solvent content.

Crystal chemistry and nomenclature of fillowite-type phosphates

2021 ◽  
Vol 59 (4) ◽  
pp. 781-796
Author(s):  
Frédéric Hatert ◽  
Edward S. Grew ◽  
Pietro Vignola ◽  
Nicola Rotiroti ◽  
Fabrizio Nestola ◽  
...  
Keyword(s):  
Diffraction Data ◽  
Divalent Cations ◽  
Complex Structure ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Cation Sites ◽  
Cation Distributions

ABSTRACT The crystal chemistries of five samples of minerals belonging to the fillowite group were structurally investigated: (A) fillowite from the Buranga pegmatite, Rwanda; (B) fillowite from the Kabira pegmatite, Uganda; (C) johnsomervilleite from Loch Quoich, Scotland; (D) johnsomervilleite from the Malpensata pegmatite, Italy; and (E) chladniite from the Sapucaia pegmatite, Minas Gerais, Brazil. Their crystal structures were refined in space group R (No. 148), using single-crystal X-ray diffraction data, to R1 values of (A) 3.79%, (B) 3.52%, (C) 4.14%, (D) 4.04%, and (E) 5.59%. Unit-cell parameters are: (A) a = 15.122(1), c = 43.258(4) Å; (B) a = 15.125(1), c = 43.198(3) Å; (C) a = 15.036(2), c = 42.972(9) Å; (D) a = 15.090(2), c = 43.050(9) Å; and (E) a = 15.1416(6), c = 43.123(2) Å. The asymmetric unit contains 15 cation sites with coordinations ranging from V to IX, as well as six P sites. The complex structure can be split into three types of chains running parallel to the c axis. These chains are composed of edge- and face-sharing polyhedra. Detailed cation distributions were determined for all five samples, and their comparison allowed us to establish the general formula A3BC11(PO4)9 for fillowite-type phosphates, where A represents the group of sites mainly occupied by Na, B the Ca sites, and C the sites containing the divalent cations Fe2+, Mn, and Mg. This formula was accepted by the CNMNC, and the four valid mineral species occurring in the fillowite group are fillowite (C = Mn), johnsomervilleite (C = Fe2+), chladniite (C = Mg), and galileiite (B and C = Fe2+). Stornesite-(Y) is discredited, since this mineral corresponds to Y-bearing chladniite.

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