Crystallographic data of the selenoenzyme glutathione peroxidase

Glutathione peroxidase prepared from bovine erythrocytes yields small, but well-ordered plate-like crystals. X-ray investigation shows them to belong to monoclinic space group C2. Unit cell dimensions are: $\text{a = 90.4}\text{A}\text{?}\text{, b = 109.5}\text{A}\text{?}\text{, c = 58.6}\text{A}\text{?}$, β = 99 ° ± 15 min. The crystal density is ?_c = 1.36 ± 0.02 g.cm^?3. Consequently, the asymmetric unit of the crystal cell is occupied by one tetrameric molecule of M_r 84,000. Matthew's (1968) parameter Γ_M is calculated to be 1.71 ų/dalton.     

Crystallographic study of plastocyanins

Crystals of plastocyanins from pea and corn leaves have been obtained. Both are suitable for X-ray structure analysis with a resolution up to 1.8 Å. The crystal form of plastocyanin from pea leaves belongs to the space group P2₁2₁2₁ with unit cell dimensions: $\text{a = 49.0}\text{A}\text{?}\text{, b = 53.3}\text{A}\text{?}\text{, c = 82.6}\text{A}\text{?}$. The assumed number of protein molecules per asymmetric unit of the unit cell is two. Crystals of the oxidized (Cu²⁺) and reduced (Cu⁺) forms are isomorphic. No essential differences in spot intensities for the main zone with a resolution of 3 Å were revealed. The crystal form of plastocyanin from corn leaves belongs to the space group P1 with unit cell parameters: $\text{a = 24.8}\text{A}\text{?}\text{, b = 30.0}\text{A}\text{?}\text{, c = 58.5}\text{A}\text{?}$ and α = 96° 10′, β = 87°08′, γ = 78°40′. The assumed number of protein molecules per asymmetric unit is two.     

Manganese superoxide dismutases from Escherichia coli and from yeast mitochondria: Preliminary X-ray crystallographic studies

The Mn superoxide dismutase from Escherichia coli has been obtained in three crystal forms: (I) from 68% saturated (NH₄)₂SO₄, space group P222 or P222₁, $\text{a = 47}\text{A}\text{?}\text{, b = 103}\text{A}\text{?}\text{, c = 47.5}\text{A}\text{?}$, with one subunit per asymmetric unit; (II) from 50% polyethylene glycol 6000, space group C222₁ (with approx. P4₁2₁2 symmetry), $\text{a = 101}\text{A}\text{?}\text{, b = 108}\text{A}\text{?}\text{, c = 180}\text{A}\text{?}$, with four subunits (2 molecules) per asymmetric unit; (III) from 52% polyethylene glycol with a different method of preparing the enzyme solution, space group P2₁2₁2, $\text{a = 47}\text{A}\text{?}\text{, b = 51}\text{A}\text{?}\text{, c = 188}\text{A}\text{?}$, with two subunits per asymmetric unit.The yeast mitochondrial Mn superoxide dismutase has yielded the same crystal form both from 30% 2-methyl-2,4-pentane diol and from 23% polyethylene glycol 6000: space group P2₁2₁2₁, $\text{a = 63}\text{A}\text{?}\text{, b = 115}\text{A}\text{?}\text{, c = 125}\text{A}\text{?}$, with four subunits (one molecule) per asymmetric unit.A full X-ray crystallographic study of at least one of these enzymes is planned.     

Crystallographic data for lysozyme from the egg white of the Embden goose

Two crystal forms of lysozyme from the egg white of the embden goose (Anser anser) have been obtained, both of which are suitable for X-ray diffraction analysis. The monoclinic form has space group P2₁ with cell dimensions $\text{a = 38.3}\text{A}\text{?}\text{, b = 65.7}\text{A}\text{?}\text{, c = 45.2}\text{a}\text{?}$, β = 116 ° and the triclinic form (space group P1) has cell dimensions of $\text{a = 39.9}\text{A}\text{?}\text{, b = 42.2}\text{A}\text{?}\text{, c = 57.9}\text{A}\text{?}$ and α = 98.8 °, β = 102.5 °, γ = 90.5 °.     

Particle and crystal symmetry of erysimum latent virus

Erysimum latent virus, a tymovirus, contains 180 protein subunits arranged in a T = 3 icosahedral surface lattice. A cubic crystal form (with space group P2₁3 and $\text{a = 414}\text{A}\text{?}$) and a monoclinic form (space group B2, $\text{a = 442}\text{A}\text{?}\text{, b = 422}\text{A}\text{?}\text{, c = 387}\text{A}\text{?}\text{, γ = 95 °}$) have been observed. The asymmetric units of the two crystal forms contain one-third and one whole virus particle, respectively. Two possible packing arrangements of the virus particles in the monoclinic unit cell have been deduced from the low-angle diffraction patterns. X-ray diffraction data from the monoclinic crystals extend to at least 3·7 Å resolution.     

Crystallographic analysis of the phytoagglutinin from Abrus precatorius by X-ray diffraction and electron microscopy

The lectin from the seeds of Abrus precatorius has been crystallized and the crystals subjected to study by X-ray diffraction and electron microscopy. Three closely related crystal forms were obtained, of orthorhombic space group P2₁2₁2₁ with $\text{a = 138}\text{A}\text{?}$, $\text{b = 142}\text{A}\text{?}$, and $\text{c = 173}\text{A}\text{?}$, of tetragonal space group P4₁2₁2 with $\text{a = b = 136}\text{A}\text{?}$, $\text{c = 176}\text{A}\text{?}$, and a twinned intermediate of the first two. From electron microscopy and two-dimensional spatial filtering of electron micrographs of the crystals, the molecule appears to consist of four similar domains grouped in a roughly planar diamond-shaped arrangement having a local intramolecular dyad axis. The average diameter of the Abrus lectin molecule is 50 to 60 Å and the individual domains appear to have a diameter of about 25 Å.     

X-ray analysis of a progesterone-binding protein (uteroglobin): preliminary results

Uteroglobin, which is a progesterone-binding protein of the rabbit uterine secretion, has been crystallized and subjected to X-ray diffraction analysis. Two crystalline forms have been observed: a triclinic one ($\text{P1, Z = 2, a = 36.36 (4)}\text{A}\text{?}\text{, b = 37.40 (4)}\text{A}\text{?}\text{, c = 53.28 (4)}\text{A}\text{?}\text{, α = 104.6 (1) °, β = 97.0 (1) °, γ = 111.3(1) °}$); and an orthorhombic one for which the cell is C-centred with $\text{a = 50.86 (5)}\text{A}\text{?}\text{, b = 52.22 (5)}\text{A}\text{?}\text{, c = 47.28 (5)}\text{A}\text{?}$, space group C222₁, Z = 4. Three isomorphous derivatives have been obtained. The crystals appear suitable for detailed study of the three-dimensional structure of the protein.     

A preliminary crystallographic investigation of rabbit muscle creatine kinase

Three crystal forms of rabbit muscle creatine kinase have been grown, one of which seems suited to a high resolution X-ray diffraction study. The first form is of monoclinic space group P2₁ with $\text{a = 54}\text{A}\text{?}\text{, b = 114}\text{A}\text{?}\text{, c = 145}\text{A}\text{?}\text{, β = 91 °}$ and has as the asymmetric unit two molecules of total molecular weight 160, 000. The second form, grown in the presence of mercurials, is of space group A2 with $\text{a = 52}\text{A}\text{?}\text{, b = 165}\text{A}\text{?}\text{, c = 237}\text{A}\text{?}\text{, β = 91 °}$ and also has two molecules in the asymmetric unit. The third crystal form, grown in the presence of a high concentration of cysteine, is of apparent space group P2₁2₁2₁, but evidence indicates that the true space group may be P2₁22₁. The dimensions of the orthorhombic unit cell are $\text{a = 47}\text{A}\text{?}\text{, b = 86}\text{A}\text{?}\text{, c = 125}\text{A}\text{?}$, and the asymmetric unit contains a single protein subunit. Assuming the latter space group, then the creatine kinase molecule possesses a twofold axis relating two identical subunits.     

Crystallization of a tryptic core of the single-stranded DNA binding protein of bacteriophage T4

A tryptic core (residues 22 to 253) of the single-stranded DNA binding protein, or gene 32 protein, of bacteriophage T4 has been crystallized in four different crystal forms. One of these forms appears suitable for high-resolution X-ray crystallographic studies. It is triclinic, space group PI, with $\text{a = 67.7}\text{A}\text{?}\text{, b = 67.8}\text{A}\text{?}\text{, c = 66.0}\text{A}\text{?}\text{, α = 101.6 °, β = 107.0 °, γ = 105.2 °}$. There appear to be three protein protomers in a near-rhombohedral packing in the unit cell.     

Crystallographic data for the DD-carboxypeptidase-endopeptidase of low penicillin sensitivity excreted by Streptomyces albus g.

The dd-carboxypeptidase-endopeptidase of low penicillin sensitivity that is excreted by Streptomyces albus G has been crystallized from a polyethylene glycol (M_r 6000 to 7500) solution at pH 8.0. X-ray examination of the prismatic crystals shows that the space group is P2₁ with unit cell dimensions $\text{a = 51.1}\text{A}\text{?}\text{, b = 49.7}\text{A}\text{?}\text{, c = 38.7}\text{A}\text{?}\text{, β = 100.6 °}$ and one molecule in the asymmetric unit. A crystal suspension made in 50 mm-Tris · HCl buffer (pH 8.0) supplemented with 5 mm-MgCl₂ and 16% ($\text{w}\text{v}$) polyethylene glycol exhibits enzyme activity on the substrate Ac₂-l-Lys-d-Ala-d-Ala.     

Letter: Preliminary crystallographic data for Escherichia coli beta-lactamase

The β-lactamase (penicillinase) from Escherichia coli W3310 has been crystallized from 25% saturated ammonium sulfate solution at pH 6.9. An X-ray examination of the monoclinic crystals shows the space group is C2, with unit cell dimensions $\text{a = 47.2}\text{A}\text{?}$, $\text{b = 76.9}\text{A}\text{?}$, $\text{c = 73.3}\text{A}\text{?}$ and β = 98.6°. With Z = 4 and the molecular weight = 22,000 (Melling &; Scott, 1972), the ų/dalton ratio is 2.98. The crystals are suitable for structure analysis to at least 2.4 Å resolution.     

Letter: Crystallographic data of an L-arabinose-binding protein from Escherichia coli

Single crystals of an l-arabinose-binding protein from Escherichia coli B/r suitable for a high-resolution structural analysis have been obtained. An X-ray examination of the orthorhombic crystals shows the space group is P2₁2₁2₁, with unit cell dimensions: $\text{a = 55.3}\text{A}\text{?}\text{, b = 71.4}\text{A}\text{?}\text{and}\text{c = 77.5}\text{A}\text{?}$. The asymmetric unit contains one protein molecule with a molecular weight of 38,000.     

Letter: Crystallographic study of an esteroproteolytic enzyme

The esteroproteolytic enzyme, a serine protease from porcine pancreas, has been crystallized and characterized by X-ray diffraction. Two closely related crystal forms were observed. The unit cell dimensions of the first form are $\text{a = 59.2}\text{A}\text{?}\text{, b = 96.4}\text{A}\text{?}\text{and}\text{c = 47.4}\text{A}\text{?}$, space group P2₁2₁2 with one molecule (mol. wt 30,000) per asymmetric unit. The unit cell dimensions of the second form are $\text{a = 59.2}\text{A}\text{?}\text{, b = 96.4}\text{A}\text{?}\text{and}\text{c = 94.8}\text{A}\text{?}$, space group P2₁2₁2₁. Mercury derivatives of enzyme inhibitors were used to obtain multiple isomorphous heavy-atom substituents suitable for phase determination.     

Structure of a bacteriochlorophyll-protein from the green photosynthetic bacterium Chlorobium limicola: crystallographic evidence for a trimer

Crystals of the bacteriochlorophyll-protein from the green photosynthetic bacterium Chlorobium limicola, previously described by J. M. Olson et al. (1969), have been re-examined by X-ray diffraction. The space group is P6₃, as reported in the earlier work, but revised cell dimensions, $\text{a = b = 112.4 ± 0.4}\text{A}\text{?}\text{, c = 98.4 ± 0.4}\text{A}\text{?}$, were obtained, leading to a unit cell volume one third of that reported previously. Correction of this error leads to the conclusion that the bacteriochlorophyll-protein complex must be a trimer consisting of three identical subunits arranged about a crystallographic symmetry axis. Also a new trigonal crystal form of the bacteriochlorophyll-protein has been obtained, and is consistent only with a molecule composed of three identical or near-identical subunits. Models of the molecular packing for both crystal forms are presented.The molecular weight of the bacteriochlorophyll-protein complex, determined from crystal density measurements, is (1.53 ± 0.23) × 10⁵, and the overall molecular dimensions are about 55 Å along the trimer axis, and 83 Å at right angles to this. There are probably seven bacteriochlorophyll molecules in each subunit.     

Crystallization of a DNA-unwinding protein: Preliminary X-ray analysis of fd bacteriophage gene 5 product

The gene 5 protein from bacteriophage fd, which binds to single-stranded progeny fd DNA, was obtained as large single crystals and subjected to X-ray diffraction analysis. The crystals are of monoclinic space group C2 with $\text{a = 75.8}\text{A}\text{?}\text{, b = 28.0}\text{A}\text{?}\text{, c = 42.5}\text{A}\text{?}\text{and}\text{β = 103 °12′}$. The unit cell has one molecule of 9800 daltons as the asymmetric unit.     

Crystallization of lactate dehydrogenase from Bacillus stearothermophilus

Crystals of lactate dehydrogenase from Bacillus stearothermophilus have been obtained in five different crystal morphologies belonging to at least two different space groups. Apo-lactate dehydrogenase can crystallize in space group P6₁22 or P6₅22 ($\text{a = 87}\text{A}\text{?}\text{and}\text{c = 358}\text{A}\text{?}$). A complex of lactate dehydrogenase with NADH and the effector fructose 1,6-diphosphate can crystallize in the same space group as the apoenzyme and in P6₃22 ($\text{a = 290}\text{A}\text{?}\text{, c = 146}\text{A}\text{?}$). Both forms are suitable for high resolution X-ray diffraction studies.     

Crystallization and preliminary X-ray diffraction studies of colicin E3 immunity protein

Immunity protein, an inhibitor of the ribonuclease activity of the protein antibiotic colicin E₃, crystallizes in the orthorhombic space group C222 with cell dimensions $\text{a = 78·7}\text{A}\text{?}\text{, b = 54·1}\text{A}\text{?}\text{, c = 36·1}\text{A}\text{?}$ and one molecule of M_r 9800 per asymmetric unit. The crystals are suitable for high resolution X-ray analysis.     

Electron diffraction determination of chain packing of a ketonic insect wax

Single crystal electron diffraction patterns are obtained from thin microcrystals of two polymorphic forms of a pure ketonic wax secreted by the wooly alder aphid, Prociphilus tessellatus. One crystalline form gives intensity data which agree well with the commonly observed O_⊥ methylene subcell. The unit cell constants for the projection are $\text{a = 7.52}\text{A}\text{?}$ and $\text{b = 5.05}\text{A}\text{?}$. The other polymorph, which is found less often, is a rectangular supercell with pseudohexagonal symmetry in the intensity-weighted hk0 reciprocal net. The supercell parameters in projection are $\text{a = 42.06}\text{A}\text{?}$, and $\text{b = 9.12}\text{A}\text{?}$ with the inner order hexad of intense spots occurring at 4.20 Å.     

Structure of Bence--Jones protein, Pav: an initial report

A Bence-Jones protein, Pav, was isolated from the urine of a myeloma patient. Crystals were grown by five different methods yielding different morphologies with slightly changed cell parameters, but the space group was the same (P2₁2₁2₁) in every case and X-ray patterns appeared to be identical. The cell parameters are: $\text{a = 93.6 (4)}\text{to}\text{95.1(4)}\text{A}\text{?}\text{, b = 92.7(3)}\text{A}\text{?}\text{and}\text{c = 72.8(2)}\text{A}\text{?}$. The crystal density and solvent content are approximately 1.128 g/cm³ and 0.64, respectively. Chemical evidence suggest that the two subunits of Pav are identical in chemical sequence. The crystal structure may prove useful in defining allosteric effects among antibody domains.     

Purification and preliminary crystallographic studies on azurin and cytochrome c' from Alcaligenes denitrificans and Alcaligenes sp. NCIB 11015.

Purification and crystallisation procedures are reported for azurin and cytochrome c′ from Alcaligenes denitrificans and Alcaligenes sp. NCIB 11015. The azurin crystals from A. denitrificans are suitable for high-resolution X-ray structure analysis. They are orthorhombic, space group C222₁ (with marked tetragonal pseudo-symmetry), cell dimensions $\text{a = 75.0}\text{A}\text{?}\text{, b = 74.1}\text{A}\text{?}\text{, c = 99.5}\text{A}\text{?}$, with two molecules per asymmetric unit. The cytochrome c′ crystals from both species are hexagonal, space group P6₁22 (or P6₅22), cell dimensions $\text{a = b = 54.7}\text{A}\text{?}\text{, c ~ 185}\text{A}\text{?}$, γ = 120 °, with one subunit (molecular weight 14,000) in the asymmetric unit.