共查询到20条相似文献,搜索用时 46 毫秒
1.
Yuri N. Chirgadze Marina B. Garber Stanislav V. Nikonov 《Journal of molecular biology》1977,113(2):443-447
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: . 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: and α = 96° 10′, β = 87°08′, γ = 78°40′. The assumed number of protein molecules per asymmetric unit is two. 相似文献
2.
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 . There appear to be three protein protomers in a near-rhombohedral packing in the unit cell. 相似文献
3.
Crystals of histidinol dehydrogenase (EC 1.1.1.23) from Salmonella typhimurium have been obtained in large size suitable for single crystal X-ray studies. The following crystal data were obtained on examination of a number of X-ray precession photographs; crystal system monoclinic, , , , β = 124.5 °, space group C2. The density of the crystal measured by flotation in bromobenzene/xylene mixture is 1.186 g/cm3. There is one dimer molecule of molecular weight 80,000 in one crystallographically asymmetric unit. 相似文献
4.
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 ) and a monoclinic form (space group B2, ) 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. 相似文献
5.
B C Wang C S Yoo R Y Hwan M Sax W E Brown M Michaels 《Journal of molecular biology》1977,116(3):619-625
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: . 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. 相似文献
6.
Edwin M. Westbrook Robert I. Lehrer Michael E. Selsted 《Journal of molecular biology》1984,178(3):783-785
A hexagonal crystal form (P6322, ) and a monoclinic form (P21, ) of neutrophil cationic protein NP2, isolated from rabbit leukocytes, have been characterized. The monoclinic form, containing two promoters (Mr = 3844) per asymmetric unit, diffracts to at least 1.8 Å and is suitable for high-resolution structural studies. 相似文献
7.
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: , 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 Mr 84,000. Matthew's (1968) parameter ΓM is calculated to be 1.71 Å3/dalton. 相似文献
8.
Bovine neurophysin II, a hormone carrier protein, has been crystallized as a binary complex with l-phenylalanyl-l-tyrosine amide, a peptide known to bind neurophysin at its hormone binding site. The crystals belong to space group P212121 with cell constants of . The density of the crystal is 1.156 g/cm3. There is a tetramer or two dimers in an asymmetric unit. 相似文献
9.
R.E. Fenna 《Journal of molecular biology》1982,161(1):203-210
Three new crystal forms of cow α-lactalbumin are described. A trigonal form in space group P3121 or P3221 has unit cell dimensions: . A hexagonal form in space group P622 has unit cell dimensions: . A second trigonal form grown in the presence of calcium ions belongs to space group P321 with unit cell dimensions: . The significance of these new crystal forms to the structure determination of cow α-laetalbumin is discussed. 相似文献
10.
The plant seed protein canavalin has been crystallized alter trypsinization by using vapor diffusion to effect isoelectric precipitation. The space groups and cell dimensions are R3 with and having extremely high R32 pseudo symmetry, P63 with . X-ray data combined with electron microscopy suggests the molecule to be composed of six identical subunits. each of 18,500 daltons, arranged in a staggered hexameric ring and related by perfect or near perfect 3 2 point group symmetry. The outside diameter of the molecule is approximately 65 Å and there appears to be a large solvent channel coincident with the molecular triad. 相似文献
11.
A McPherson 《Journal of molecular biology》1973,81(1):83-86
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 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 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 , 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. 相似文献
12.
Two new crystal forms of oxidized uteroglobin have been obtained. An orthorhombic one () and a monoclinic one (). Both were grown at pH ~7.0 and diffract to a resolution of 2·1 to 2·2 Å. Data collections for native crystals have been recorded with an automatic four-circle diffractometer. 相似文献
13.
Crystals of the bacteriophage λ Cro repressor protein that are suitable for X-ray diffraction studies have been obtained. Preliminary crystallographic analysis reveals that the space group is R32, the cell dimensions in the hexagonal system are , and there are three dimers per asymmetric unit. 相似文献
14.
Edwin M. Westbrook Paul B. Sigler Helen Berman Jenny P. Glusker Gerard Bunick Ann Benson Paul Talalay 《Journal of molecular biology》1976,103(3):665-667
A monoclinic crystal form (, β= 130.1 °) of Δ5-3-ketosteroid isomerase from Pseudomonas testosteroni (EC 5.3.3.1), grown at pH 7.0, has been characterized. Crystal-density measurements show that the asymmetric unit contains 12 protomers (Mr = 13,394). 相似文献
15.
Keiichi Fukuyama Sherin S. Abdel-Meguid Michael G. Rossmann 《Journal of molecular biology》1981,150(1):33-41
Reassembled alfalfa mosaic virus coat protein was partially digested with trypsin to remove the first 26 amino acids (Bol et al., 1974). These particles are empty icosahedral protein shells built with 60 alfalfa mosaic virus protein subunits. This aggregate has been crystallized in two different crystal forms, one of which diffracts X-rays to at least 3.4 Å resolution. The type I crystals (space group ) contain two particles per cell separated by 195 Å with each sitting on a 3-fold axis. The type II crystals contain three particles per cell in space group P31or P32 (). Other T = 1 viral particles have very similar diameters. 相似文献
16.
Douglas L. Dorset 《Chemistry and physics of lipids》1975,14(4):291-296
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 and . 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 , and with the inner order hexad of intense spots occurring at 4.20 Å. 相似文献
17.
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 , β = 116 ° and the triclinic form (space group P1) has cell dimensions of and α = 98.8 °, β = 102.5 °, γ = 90.5 °. 相似文献
18.
Karl M. Beem Jane S. Richardson David C. Richardson 《Journal of molecular biology》1976,105(2):327-332
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, , with one subunit per asymmetric unit; (II) from 50% polyethylene glycol 6000, space group C2221 (with approx. P41212 symmetry), , 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, , 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, , with four subunits (one molecule) per asymmetric unit.A full X-ray crystallographic study of at least one of these enzymes is planned. 相似文献
19.
Systematic crystallization studies on brewer's yeast aspartic acid transfer RNA have yielded different crystal forms, one of them diffracting to 3 Å resolution. The high resolution crystal form is orthorhombic ( with one molecule per asymmetric unit) and is stable for over four days under X-rays. 相似文献
20.
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 , , and , of tetragonal space group P41212 with , , 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. 相似文献