Crystallization of the secondary alcohol dehydrogenase from Thermoanaerobacter ethanolicus 39E.

The secondary alcohol dehydrogenase from the thermophile Thermoanaerobacter ethanolicus 39E has been crystallized at 40 degrees C by vapour difussion using polyethelene glycol as a precipitant. The orthorhombic crystals belong to the space group P 2(1)2(1)2 with cell constants of a=170.0 Angstrom, b=125.7 Angstrom and c=80.5 Angstrom. A native X-ray diffraction data set has been collected to 2.7 Angstrom resolution.

Isolation, characterization and biological activity of acidic phospholipase A(2) isoforms from Bothrops jararacussu snake venom

Acidic phospholipase A(2) (PLA(2)) isoforms in snake venoms, particularly those from Bothrops jararacussu, have not been characterized. This article reports the isolation and partial biochemical, functional and structural characterization of four acidic PLA(2)s (designated SIIISPIIA, SIIISPIIB, SIIISPIIIA and SIIISPIIIB) from this venom. The single chain purified proteins contained 122 amino acid residues and seven disulfide bonds with approximate molecular masses of 15 kDa and isoelectric points of 5.3. The respective N-terminal sequences were: SIIISPIIA-SLWQFGKMIDYVMGEEGAKS; SIIISPIIB-SLWQFGKMIFYTGKNEPVLS; SIIISPIIIA-SLWQFGKMILYVMGGEGVKQ and SIIISPIIIB-SLWQFGKMIFYEMTGEGVL. Crystals of the acidic protein SIIISPIIIB diffracted beyond 1.8 Angstrom resolution. These crystals are monoclinic with unit cell dimensions of a = 40.1 Angstrom, b = 54.2 Angstrom and c = 90.7 Angstrom. The crystal structure has been refined to a crystallographic residual of 16.1% (R-free = 22.9%). Specific catalytic activity (U/mg) of the isolated acidic PLA(2)s were SIIISPIIA = 290.3 U/mg; SIIISPIIB = 279.0 U/mg; SIIISPIIIA = 270.7 U/mg and SIIISPIIIB = 96.5 U/mg. Although their myotoxic activity was low, SIIISPIIA, SIIISPIIIB and SIIISPIIIA showed significant anticoagulant activity. However, there was no indirect hemolytic activity. SIIISPIIIB revealed no anticoagulant, but presented indirect hemolytic activity. With the exception of SIIISPIIIB, which inhibited platelet aggregation, all the others were capable of inducing time-independent edema. Chemical modification with 4-bromophenacyl bromide did not inhibit the induction of edema, but did suppress other activities. (C) 2003 Editions scientifiques et medicales Elsevier SAS. All rights reserved.

Crystallization and preliminary X-ray diffraction analysis of the lectin from Canavalia gladiata seeds

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Crystallization and X-ray diffraction data analysis of human deoxyhaemoglobin A(0) fully stripped of any anions

In this work, initial crystallographic studies of human haemoglobin (Hb) crystallized in isoionic and oxygen-free PEG solution are presented. Under these conditions, functional measurements of the O-2-linked binding of water molecules and release of protons have evidenced that Hb assumes an unforeseen new allosteric conformation. The determination of the high-resolution structure of the crystal of human deoxy-Hb fully stripped of anions may provide a structural explanation for the role of anions in the allosteric properties of Hb and, particularly, for the influence of chloride on the Bohr effect, the mechanism by which Hb oxygen affinity is regulated by pH. X-ray diffraction data were collected to 1.87 Angstrom resolution using a synchrotron-radiation source. Crystals belong to the space group P2(1)2(1)2 and preliminary analysis revealed the presence of one tetramer in the asymmetric unit. The structure is currently being refined using maximum-likelihood protocols.

Crystallization, preliminary X-ray analysis and molecular-replacement solution of the carboxy form of haemoglobin I from the fish Brycon cephalus

Haemoglobin, the 'honorary enzyme' [Brunori (1999), Trends Biochem. Sci. 24, 158-161], constitutes a prime prototype for allosteric models. Here, the crystallization and preliminary X-ray analysis of haemoglobin I from the South American fish Brycon cephalus are reported. X-ray diffraction data have been collected to 2.5 Angstrom resolution using synchrotron radiation (LNLS). Crystals were determined to belong to the space group P6(1)22 and preliminary structural analysis revealed the presence of one dimer (alpha beta) in the asymmetric unit. The structure was determined using standard molecular-replacement techniques.

Disulfide Biochemistry in 2-Cys Peroxiredoxin: Requirement of Glu50 and Arg146 for the Reduction of Yeast Tsa1 by Thioredoxin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structure of the polypeptide crotamine from the Brazilian rattlesnake Crotalus durissus terrificus

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Crystallization and preliminary X-ray diffraction studies of an L-amino-acid oxidase from Lachesis muta venom

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Preliminary X-ray crystallographic studies of a Lys49-phospholipase A(2) homologue from Bothrops pirajai venom complexed with p-bromophenacyl bromide and alpha-tocopherol inhibitors

PrTX-I, a non-catalytic and myotoxic Lys49-PLA(2) from Bothrops pirajai venom has been crystallized alone and in complex with bromophenacyl bromide (BPB), alpha-tocopherol and alpha-tocopherol acetate inhibitors. These crystals have shown to diffract X-rays between 2.34 and 1.65 angstrom resolution. All complexes crystals are isomorphous and belong to the space group P2(1) whereas native PrTX-I crystals belong to the P3(1)21.

Experimental and theoretical studies on the enhanced photoluminescence activity of zinc sulfide with a capping agent

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Crystallographic and spectroscopic characterization of a molecular hinge: Conformational changes in bothropstoxin I, a dimeric Lys49 phospholipase A2 homologue

Bothropstoxin I(BthTX-I) from the venom of Bothrops jararacussu is a myotoxic phospholipase A2 (PLA2) homologue which, although catalytically inactive due to an Asp49-->Lys substitution, disrupts the integrity of lipid membranes by a Ca2+-independent mechanism, the crystal structures of two dimeric farms of BthLTX-I which diffract X-rays eo resolutions of 3.1 and 2.1 Angstrom have been determined, the monomers in both structures are related by an almost perfect twofold axis of rotation and the dimer interfaces are defined by contacts between the N-terminal alpha-helical regions and the tips of the beta-wings of partner monomers. Significant differences in the relative orientation of the monomers in the two crystal forms results in open and closed dimer conformations, Spectroscopic Investigations of BthTX-I in solution have correlated these conformational differences with changes in the intrinsic fluorescence emission of the single tryptophan residues located at the dimer interface, the possible relevance of this structural transition in the Ca2+-independent membrane damaging activity is discussed. (C) 1998 Wiley-Liss, Inc.

Crystal structure of hemoglobin from the maned wolf (Chrysocyon brachyurus) using synchrotron radiation

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Synchrotron X-ray powder diffraction data of atorvastatin

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Crystal structure of bis(acetylacetonato)bis(quinoline)nickel(II), Ni(C5H14O2N)(2)(C9H7N)(2)

C28H28N2NiO4, triclinic, P (1) over bar (no. 2), a = 7.9202(6) angstrom, b = 8.0496(6) angstrom, c = 10.246(1) angstrom, alpha = 97.15(1)degrees, beta = 106.68(1)degrees, gamma = 94.686(9)degrees, V = 616.1 angstrom(3), Z = 1, R-gt(F) = 0.028, wR(ref)(F-2) = 0.078, T = 293 K.

THE CRYSTAL-STRUCTURE OF BENZOYL-HISTIDINE MONOHYDRATE

The crystal structure of benzoyl-histidine monohydrate (BYLH hereafter), C-13H-12N-3O-3. H2O was determined from three dimensional data of 3012 independent reflections measured on a Enraf-Nonius (CAD4) single crystal diffractometer. The compound crystallizes in the orthorhombic space group P2(1)2(1)2(1) with cell dimensions alpha = 7.102(1) angstrom, b = 13.783(3) angstrom, c = 14.160(4) angstrom, V = 1385.92 angstrom-3, F.W. = 277.28, F(000) = 584 Q(calc) = 1.32 g cm-3 and Z = 4.The structure was solved with direct methods. All positional and anisotropic thermal parameters were refined by full-matrix least-squares calculations. The final reliability factor was R = 0.040, while the weighted one was Rw = 0.034. The H atoms found in the difference Fourier map were refined isotropically.The compound consists of a histidine molecule bound to a benzoyl group. There is also a cocrystallized water molecule stabilized through a hydrogen bridge.The 5-membered ring of the histidine has its tautomeric form, after the transfer of the H atom from the N(delta) to the N(epsilon) atom of the ring. There is an sp2 conformation around C6 while the conformation around C3 is that of sp3. The histidine ring forms with the benzene ring a dihedral angle of 109.8(1)-degree.All angle values and bond distances agree very well with the expected values in the literature.