Preparation and X-ray characterization of four new crystal forms of jacalin, a lectin from Artocarpus integrifolia

Four new crystal forms of the anti-T lectin from jackfruit (Artocarpus integrifolia) have been prepared and characterized. Three of them, two monoclinic (P21, a = 59.4 A, b = 83.3 A, c = 63.5 A, beta = 107.7 degrees; C2, a = 106.1 A, b = 53.9 A, c = 128.0 A, beta = 95.0 A) and one orthorhombic (C222(1), a = 98.1 A, b = 67.3 A, c = 95.1 A) were grown with 2-methylpentan-2,4-diol (MPD) as the precipitant while the fourth, an hexagonal form (P6(1)22, a = b = 129.6 A, c = 157.9 A), was obtained in the presence of methyl-alpha-D-galactopyranoside with polyethylene glycol 4000 as the precipitant. The reported relative molecular mass (Mr) of the lectin was found to be inconsistent with the solvent content of the crystals estimated using measured densities. The Mr was redetermined using size-exclusion chromatography in the presence of methyl-alpha-D-galactopyranoside and Ferguson-plot analysis of mobilities in polyacrylamide gel electrophoresis. The redetermined Mr (66,000) is consistent with the measured crystal densities. The orthorhombic and the hexagonal forms, which have one half molecule and one molecule, respectively, in the asymmetric unit, are suitable for high-resolution X-ray analysis.     

Crystallization and preliminary diffraction studies of malate dehydrogenase from Streptomyces aureofaciens

Purified malate dehydrogenase (MDH) of Streptomyces aureofaciens was crystallized either in the absence or in the presence of NADH or NADPH coenzymes by hanging-drop vapour-diffusion method. An X-ray study has shown, that MDH crystals belong to space group C222(1) with unit-cell parameters a = 53.2 A, b = 104.6 A, c = 520.0 A, alpha = beta = gamma = 90( degrees ), MDH-NADH crystals to space group C2 with unit-cell parameters a = 51.5 A, b = 51.5 A, c = 256 A, alpha = beta = gamma = 90( degrees ), and MDH-NADPH crystals to space group C222(1) with unit-cell parameters a = 72, A b = 72 A, c = 520 A, alpha = beta = gamma = 90( degrees ). The crystal of native MDH diffracted to 2.1 A resolution.     

Crystallization and preliminary X-ray diffraction studies of the engrailed homeodomain and of an engrailed homeodomain/DNA complex

The homeodomain from the engrailed protein of Drosophila has been crystallized from ammonium phosphate at pH 6.8. The crystals form in space group P6(1)22 (or P6(5)22), with cell dimensions a = b = 44.8 A and c = 118.2 A. These crystals diffract to 1.8 A resolution. A complex containing the engrailed homeodomain and a duplex DNA site also has been crystallized. The cocrystals form in space group C2 with a = 131.2 A, b = 45.5 A, c = 72.9 A and beta = 119.0 degrees. These crystals diffract to 2.6 A resolution.     

Crystallization and preliminary X-ray studies of the Ia component of Clostridium perfringens iota toxin complexed with NADPH.

A recombinant Ia component of Clostridium perfringens iota toxin, which ADP-ribosylates actin, was crystallized by the hanging drop vapor diffusion method using PEG4000 as a precipitating agent. The crystals were obtained in the presence of NADPH, which is similar to a real substrate, NADH, and belongs to the space group P1 (a = 47.9 A, b = 54.5 A, c = 103.1 A, alpha = 99.0 degrees, beta = 93.3 degrees, and gamma = 107.2 degrees ). The Matthews coefficient of native crystal was 2.7, assuming 2 mol/asymmetric unit. Native data were collected at 2.4-A resolution. The results from a heavy-atom search showed that lanthanide ions (samarium, holmium) altered the molecular packing, judging from the unit-cell difference. The crystals also belonged to the space group P1 (a = 47.7 A, b = 53.9 A, c = 54.6 A, alpha = 68.9 degrees, beta = 78.3 degrees, and gamma = 73.7 degrees ), which is consistent with only one molecule per asymmetric unit.     

Crystallization of murine major histocompatibility complex class I H-2Kb with single peptides.

X-ray quality crystals of a soluble murine class I H-2Kb molecule complexed with three different peptide antigens were grown in several forms by streak seeding and macroseeding methods. Co-crystals with VSV-8 (RGYVYGQL), OVA-8 (SIINFEKL) and SEV-9 (FAPGNYPAL) peptides were grown either from NaH2PO4/HPO4 or from polyethylene glycol 4000 within the pH range 5.0 to 7.5, with the use of 4-methyl-2-pentane diol (MPD) as an additive. The VSV-8 crystals grew in space groups P1, with cell dimensions a = 63.1 A, b = 69.1 A, c = 72.0 A, alpha = 89.9 degrees, beta = 77.1 degrees, gamma = 123.3 degrees and P2(1)2(1)2, with a = 138.1 A, b = 88.6 A, c = 45.7 A, and diffract to 2.9 and 2.3 A, respectively. Crystals of the SEV-9 complex grew from similar crystallization conditions to those of the orthorhombic VSV-8 complex with similar cell parameters and diffract to at least 2.5 A resolution. Crystals of the OVA-8 complex were obtained from either phosphate (space group C2, a = 118.7 A, b = 61.6 A, c = 85.3 A, beta = 108.4 degrees) or polyethylene glycol (space group P1, a = 64.5 A, b = 71.0 A, c = 66.3 A, alpha = 89.7 degrees, beta = 95.7 degrees, gamma = 123.3 degrees) and diffract to 3 A resolution. The crystallization procedures used here significantly increased the rate and production of X-ray quality crystals.     

Two crystal forms of the lentil lectin diffract to high resolution.

The legume lectins are an important class of polysaccharide-binding proteins with a wide range of biochemical and immunological applications. Two high-resolution crystal forms are obtained for the lentil (Lens culinaris) lectin: a monoclinic P21 and an orthorhombic P212121. The unit cell dimensions for the monoclinic form are a = 58.0 A, b = 56.0 A, c = 82.1 A, beta = 104.4 degrees, while for the orthorhombic form a = 56.4 A, b = 74.6 A, c = 124.9 A. The asymmetric unit contains one dimer in both cases. The crystals diffract to 1.7 A resolution using synchrotron radiation. Preliminary data have been collected to 2.3 A on both crystal forms using a conventional X-ray source.     

Preliminary crystallographic data and primary sequence for anti-peptide Fab' B13I2 and its complex with the C-helix peptide from myohemerythrin

Crystals of the Fab' fragment from the monoclonal anti-peptide antibody B1312 and of the Fab'-peptide antigen complex have been characterized. The monoclonal antibodies were raised against a synthetic homologue of the C-helix of myohemerythrin (residues 69-87 in myohemerythrin). The Fab'-peptide complex crystallizes in space group P6322 with unit cell dimensions a = b = 142.5 A, c = 101.5 A, alpha = beta = 90 degrees, gamma = 120 degrees, and Z = 1. The native Fab' crystallizes in space group P212121 with unit cell dimensions a = 98.0 A, b = 151.7 A, c = 80.8 A, alpha = beta = gamma = 90 degrees, and Z = 2. Both crystal forms diffract to beyond 2.6 A resolution. We also report the cDNA and predicted amino acid sequences for the variable regions of both the light and heavy chains of this anti-peptide antibody.     

国产十四种苋属植物的染色体数目

报道了国产14种苋属植物的染色体数目。部分种的染色体数目为2n=34,即反枝苋Amaranthus retroflexus,刺苋A．spinosus,红苋A．cruentus,腋花苋A．roxburghianus,合被苋A．polygonoides,皱果苋A． viridis,凹头苋A．lividus,苋A．tricolor。其他种的染色体数目为2n=32,即尾穗苋A．caudatus,绿穗苋A． hybridus,千穗谷A．hypochendriacus,繁穗苋A．paniculatus,北美苋A．blitoides,白苋A．albus。其中腋花 苋的染色体数目为首次报道。该属染色体基数为x=16,17。两种染色体基数在苋属2个组(sect．Ama- ranthus和sect．Blitopsis)中均存在。由于苋属植物染色体大多为小型染色体,因此对苋属植物目前尚不 能进行详尽的核型分析。     

Molecular size and symmetry of the bacterioferritin of Escherichia coli. X-ray crystallographic characterization of four crystal forms

X-ray crystallographic data from four crystal forms of Escherichia coli bacterioferritin show that the molecule has a diameter in the range 119 to 128 A. Molecules are composed of 24 subunits arranged in 432 symmetry. In both size and symmetry the molecule resembles ferritin from eukaryotes. The four crystal forms are monoclinic, space group P2(1) with unit cell dimensions a = 118.7 A, b = 211.6 A, c = 123.3 A and beta = 119.1 degrees; orthorhombic, C222(1), a = 128.7 A, b = 197.1 A, c = 202.8 A; tetragonal, P4(2)2(1)2, a = b = 210.6 A, c = 145.0 A and cubic, I432, a = 146.9 A.     

Crystallographic study of endogenous alpha-amylase inhibitor from wheat

Endogenous alpha-amylase inhibitor from wheat has been crystallized by a microdialysis method. There are two forms of monoclinic crystal in a microdialysis cell with a space group of P2(1). The unit cell dimensions are a = 43.5 A, b = 64.8 A, c = 32.2 A, beta = 113 degrees for the rod-like crystal, and a = 42.5 A, b = 65.2 A, c = 32.2 A, beta = 112 degrees for the plate-like crystal. The former is suitable for structure analysis because it gives the sharp diffraction beyond 2.0 A resolution, and the latter tends to form a twin crystal. A heavy-atom derivative has been successfully prepared with the heavy-atom reagent K2PtCl4, and structure analysis is in progress.     

Crystallization and preliminary X-ray study of pig lens aldose reductase

Crystals of pig lens aldose reductase have been grown from polyethylene glycol solutions at pH 6.2 and analysed by X-ray diffraction. Two crystal forms were obtained. The first belongs to space group P1 with unit cell dimensions a = 81.3 A, b = 85.9 A, c = 56.6 A, alpha = 102.3 degrees, beta = 103.3 degrees, gamma = 79.0 degrees, with four molecules in the unit cell related by a 222 non-crystallographic symmetry. The second crystal form is hexagonal. The space group is P6(2)22 with a = b = 101 A, c = 257 A and two molecules in the asymmetric unit. Both forms are suitable for X-ray structure analysis to better than 3 A resolution.     

Crystallization and preliminary crystallographic data of a truncated derivative from the human c-Ha-ras protein

A truncated derivative of the human c-Ha-ras protein has been crystallized from polyethylene glycol 6000 solution by a vapour diffusion technique. The rectangular prism diffracts X-rays to at least 2.5 A resolution (1 A = 0.1 nm). The unit cell is monoclinic, space group P21, with unit cell parameters of a = 50.2 A, b = 110.9 A, c = 36.4 A, beta = 97.2 degrees. The unit cell contains four molecules.     

Crystallization and preliminary structural studies of neurotrophin-3.

Neurotrophin-3 (NT-3) has been crystallized in 2 forms. Orthorhombic crystals, space group P2(1)2(1)2, diffracted to 2.8 A and have cell dimensions a = 39.1 A, b = 54.0 A, and c = 65.5 A. The second form is space group P4(3)2(1)2, with cell dimensions a = b = 67.1 A, and c = 107.9 A. The tetragonal crystals diffract to 2.8 A at room temperature and 2.5 A at -100 degrees C. The unit cell dimensions change significantly upon freezing, a = b = 66.1 A, and c = 102.8 A. Phases for the orthorhombic form were obtained by molecular replacement using nerve growth factor as the search model. A partially refined model of the NT-3 dimer (75% complete) was then oriented and positioned in the tetragonal cell.     

Crystallization and preliminary crystallographic data of the Fab fragment of an anti-phenylalanine hydroxylase monoclonal antibody

Two crystal habits, one rod shaped and the other square prismatic, of the Fab fragment of a monoclonal anti-phenylalanine hydroxylase antibody have been grown using the method of vapour phase diffusion against polyethylene glycol 6000. The square prisms diffract to better than 2.8 A, belong to the space group P1 and have unit cell parameters a = 41.8 A, b = 50.3 A, c = 114.7 A, alpha = 97.6 degrees, beta = 91.7 degrees, gamma = 91.0 degrees, while the rod-shaped crystals belong to the space group P212121, have unit cell parameters a = 105.6 A, b = 119.8 A, c = 82.2 A and diffract to 3.5 A resolution.     

Crystallization of fragment D from human fibrinogen.

Fragment D from human fibrinogen has been crystallized. The fragment, which is composed of three disulfide-linked chains (alpha' beta' gamma' = 88,000), was generated with either plasmin or mild trypsin digestion. The crystals diffracted out to 3.5 A; the space group is P2(1), unit cell dimensions a = 108 A, b = 48 A, c = 167 A, beta = 106 degrees. Fragment D was also co-crystallized with the ligand GPRP-amide, in which case the space group is consistent with P212121, unit cell dimensions a = 476 A, b = 82 A, c = 432 A.     

Preliminary crystallographic studies of two C-terminally truncated copper-containing nitrite reductases from Achromobacter cycloclastes: changed crystallizing behaviors caused by residue deletion

The C-terminal segment of copper-containing nitrite reductase from Achromobacter cycloclastes (AcNiR) has been found essential for maintaining both the quaternary structure and the enzyme activity of AcNiR. C-terminal despentapeptide AcNiR (NiRc-5) and desundecapeptide AcNiR (NiRc-11) are two important truncated mutants whose activities and stability have been affected by residue deletion. In this study, the two mutants were crystallized using the hanging drop vapor diffusion method. Crystals of NiRc-5 obtained at pH 5.0 and 6.2 both belonged to the P2(1)2(1)2(1) space group with unit cell parameters a=99.0 A, b=117.4 A, c=122.8 A (pH 5.0) and a=98.9A, b=117.7A, c=123.0A (pH 6.2). NiRc-11 was crystallized in two crystal forms: the tetragonal form belonged to the space group P4(1) with a=b=96.0A and c=146.6A; the monoclinic form belonged to the space group P2(1) with a=86.0A, b=110.1A, c=122.7A, and beta=101.9 degrees. The crystallizing behaviors of the two mutants differed from that of the native enzyme. Such change in combination with residue deletion is also discussed here.     

Crystallization and preliminary diffraction studies of recombinant human granulocyte-stimulating factor (KW2228).

Human granulocyte colony-stimulating factor (hG-CSF) specifically stimulates proliferation of neutrophils. Two crystal forms of a mutant of hG-CSF expressed in Escherichia coli have been obtained using the hanging drop vapour diffusion method. One form is triclinic, space group P1, with cell dimensions a = 37.3 A, b = 46.4 A, c = 47.7 A, alpha = 105.5 degrees, beta = 98.0 degrees and gamma = 109.4 degrees. The other is monoclinic, space group C2, with cell dimensions a = 82.0 A, b = 49.2 A, c = 49.4 A and beta = 113.9 degrees. Both crystal forms diffract beyond 2.0 A and are suitable for X-ray analysis.     

Crystallization and preliminary analysis of the deoxyoligonucleotide d(CGTAGATCTACG)

Two crystal forms of the self-complementary DNA 12-mer d(CGTAGATCTACG) were grown by the vapour diffusion technique. Form I is in space group C2 with a = 64.8 A, b = 35.4 A, c = 24.4 A and beta = 92.2 (1 A = 0.1 nm). The crystals are grown as monoclinic blocks or hexagonal plates. There are two strands (one duplex) in the asymmetric unit. Form II crystallizes as monoclinic blocks, space group P21 with a = 64.5 A, b = 35.1 A, c = 25.2 A and beta = 91.8 degrees. This form contains four strands (2 duplexes) in the asymmetric unit. Both forms are suitable for high resolution X-ray analysis. The diffraction patterns suggest that the DNA is in a B-type conformation and that the packing in the two forms is very similar.     

Preliminary crystallographic analysis of trypanothione reductase from Crithidia fasciculata

Trypanothione reductase, a flavoprotein disulfide reductase specific to trypanosomatid parasites, has been crystallized by vapor diffusion of a protein solution (10 mg/ml) against 22% polyethylene glycol (average Mr 8000) containing 100 mM-ammonium sulfate. Crystals of a size suitable for structure determination by X-ray diffraction have been obtained by seeding protein solutions with smaller crystals. The space-group is P21 (a = 60.9 A, b = 161.8 A, c = 58.4 A, beta = 99.1 degrees). The molecular mass and volume of the unit cell suggest that there is a dimer of the enzyme in the asymmetric unit, and this is confirmed by self-rotation functions calculated using data to 4.5 A resolution. The crystals diffract to beyond 3 A resolution. Crystals of another P21 form (a = 91.3 A, b = 114.4 A, c = 92.0 A, beta = 141.3 degrees) are observed to grow under similar conditions.     

Preliminary X-ray crystallographic analysis of canine parvovirus crystals

The first diffraction pattern of a crystalline single-stranded DNA virus has been obtained. Canine parvovirus was crystallized in a monoclinic P21 unit cell with a = 264.4 A, b = 350.3 A, c = 267.8 A and beta = 90.86 degrees (1 A = 0.1 nm). The diffraction pattern extends to at least 2.8 A resolution. Packing of the particles suggests that they have a diameter around 257 A, in excellent agreement with the reported molecular weight of 5.5 x 10(6).