Small-angle X-ray study of the 50 S ribosomal subunit of Escherichia coli. A comparison of different models.

A small angle X-ray scattering curve obtained from Escherichia coli 50 S subunits has been compared with the scattering curves calculated for three-dimensional 50 S models proposed by various authors. The one proposed by Lake, Stöffler and Vasiliev showed to some extent a good agreement with our experimental data. Calculating a large number of possible particle structures we found a model which optimally fits our experimental curves, but it's two-dimensional projections differ a little from the projections of 50 S subunits observed by electron microscopy.

Quaternary structure of the giant extracellular hemoglobin of the leech Macrobdella decora.

The molecular dimensions of the extracellular hemoglobin of the leech Macrobdella decora, determined by scanning transmission electron microscopy were 29.8 nm x 19.5 nm (diameter x height) for negatively stained specimens. Measurements of molecular mass (Mm) of unstained specimens with the microscope gave Mm = 3560 +/- 160 kDa. Small-angle X-ray scattering measurements gave a diameter of 28.0(+/- 0.5) nm, radius of gyration 10.5(+/- 0.2) nm and volume 7500(+/- 300) nm3. The hemoglobin had no carbohydrate and its iron content was found to be 0.23(+/- 0.02)% (w/w), corresponding to a minimum Mm of 24,000(+/- 1300) kDa. SDS/polyacrylamide gel electrophoresis of the unreduced hemoglobin showed that it consisted of three subunits, which have apparent Mm values of 12 (1), 25 (2) and 29 kDa (3). The reduced hemoglobin consisted of four subunits, I (12 kDa), II (14 kDa), III (26 kDa) and IV (30 kDa). Subunit 1 corresponded to subunit I, subunit 2 to subunits III and IV and subunit 3 to subunit II. Partial N-terminal sequences were obtained for subunit 1, the two chains of subunit 2 and one of the two chains of subunit 3, suggesting that the hemoglobin consists of at least five different polypeptide chains. The percentage fraction of the three unreduced subunits was determined by densitometry of SDS/polyacrylamide gel patterns and quantitative determination of Coomassie R-250 dye bound to the individual bands in reduced and unreduced patterns to be, monomer (subunit I) : non-reducible subunit (subunit 2) : reducible dimer (subunit 3) = 0.35 : 0.29 : 0.35 (S.D. = +/- 0.05). This corresponded to a stoichiometry of 74 +/- 11 : 37 +/- 5 : 38 +/- 6, assuming the molecular masses to be 17 kDa, 30 kDa and 34 kDa, taking into account the anomalously high mobility of annelid globins in SDS-containing gels. The stoichiometry calculated from the amino acid compositions of the hemoglobin and the three subunits was 82 +/- 12 : 29 +/- 4 : 40 +/- 8. Gel filtration of the hemoglobin at pH 9.8, at neutral pH subsequent to dissociation at pH 4 and at neutral pH in the presence of urea and Gu.HCl provided no evidence for the existence of a putative 1/12 of the whole molecule (Mm approx. 300 kDa). Furthermore, the largest subunits obtained had Mm of 60 to 100 kDa and had a much decreased content of subunit 2, suggesting that the hemoglobin was not a simple multimeric protein. Three-dimensional reconstruction from microscope images provided a model of Macrobdella hemoglobin that is very similar to the reconstruction of Lumbricus hemoglobin: the radial mass distribution curves are virtually superimposable.(ABSTRACT TRUNCATED AT 400 WORDS)

Small-angle X-ray scattering reveals differences between the quaternary structures of oxygenated and deoxygenated tarantula hemocyanin.

Small-angle X-ray scattering (SAXS) curves have been recorded for the oxygenated and deoxygenated states of the 4 x 6-meric hemocyanin from the tarantula Eurypelma californicum. A comparison of the curves shows that the quaternary structures of the two states are different by three criteria, which all indicate that the hemocyanin is less compact in the oxygenated compared to the deoxygenated form: (a) The radius of gyration is 8.65 +/- 0.05 nm for the deoxy- and 8.80 +/- 0.05 nm for the oxy-form. (b) The maximum particle dimension amounts to 25.0 +/- 0.5 nm for the deoxy- and to 27.0 +/- 0.5 nm for the oxy-form. (c) A dip in the intramolecular distance distribution function p(r) is more pronounced and shifted to larger distances in the oxy-form. The p(r) functions based on SAXS measurements were compared to p(r) functions deduced from published electron microscopical images of three different 4 x 6-meric hemocyanins from closely related species. The p(r) functions of SAXS and electron microscopy were similar in one case, whereas in the other two cases the distance between the two 12-meric half-molecules had to be changed by 1-1.5 nm to obtain good agreement. The differences between the p(r) functions of oxygenated and deoxygenated 4 x 6-meric tarantula hemocyanin are much larger than one would expect from a comparison of X-ray structures of the oxygenated and deoxygenated states of a closely related 6-meric hemocyanin. Thus, the conformational changes upon oxygenation occur at various levels of the quaternary structure, as postulated by hierarchical theories of allosteric interactions.

The Austrian version of the Childhood Health Assessment Questionnaire (CHAQ) and the Child Health Questionnaire (CHQ).

We report herein the results of the cross-cultural adaptation and validation into the Austrian language of the parentís version of two health related quality of life instruments. The Childhood Health Assessment Questionnaire (CHAQ) is a disease specific health instrument that measures functional ability in daily living activities in children with juvenile idiopathic arthritis (JIA). The Child Health Questionnaire (CHQ) is a generic health instrument designed to capture the physical and psychosocial well-being of children independently from the underlying disease. The Austrian CHAQ CHQ were adapted from the German version of the CHAQ-CHQ, and revalidated in this study. A total of 134 subjects were enrolled: 74 patients with JIA (9.5% systemic onset, 42% polyarticular onset, 9.5% extended oligoarticular subtype, and 39% persistent oligoarticular subtype) and 60 healthy children. The CHAQ clinically discriminated between healthy subjects and JIA patients, with the systemic, polyarticular and extended oligoarticular subtypes having a higher degree of disability, pain, and a lower overall well-being when compared to their healthy peers. Also the CHQ clinically discriminated between healthy subjects and JIA patients, with the systemic onset, polyarticular onset and extended oligoarticular subtypes having a lower physical and psychosocial well-being when compared to their healthy peers. In conclusion the Austrian version of the CHAQ-CHQ is a reliable, and valid tool for the functional, physical and psychosocial assessment of children with JIA.

Small-angle X-ray study on the quaternary structure of erythrocruorin from Caenestheria inopinata.

The erythrocruorin of the clam shrimp Caenestheria inopinata was studied in sodium phosphate buffer at pH 6.8 by small-angle X-ray scattering. The following molecular parameters were determined: radius of gyration 4.77 +/- 0.05 nm, maximum dimension 14.0 +/- 0.5 nm and a volume of 640 +/- 40 nm3. A model which fits the experimental data well is presented. The model is composed of 10 subunits arranged symmetrically in two layers, whereby five subunits are always forming a ring.

[Plasma 25-hydroxycholecalciferol after daily vitamin D administration in comparison with massive single-dose prophylaxis (author's transl)]. / Plasmaspiegel des 25-Hydroxycholecalciferols nach Tages- und "Stossprophylaxe" mit Vitamin D.

The effect of daily administration of 1200 IU vitamin D3 was compared with the response to a single oral dose of 200,000 IU in 21 young infants by determination of the plasma 25-OHCC levels. After about one week the mean value recorded in group 1 was 27 +/- 13 ng/ml; the corresponding value in group 2 was 127 +/- 78.4 ng/ml. At the second control examination about one month subsequently, the mean values were 61 +/- 26.2 ng/ml and 104 +/- 69.0 ng/ml respectively. The wide range of values found in the single-dose group clearly demonstrates the advantage of daily vitamin D administration for routine prophylaxis against rickets in infancy.

[Serum levels of 25-hydroxycholecalciferol (25-OH-D3) in children of different age groups (author's transl)]. / Serumspiegel des 25-Hydroxycholecalciferols (25-OH-D3) bei Kindern verschiedener Altersstufen.

Serum 25-OH-D3 levels were determined in 78 children aged 6 weeks to 15 years, in March 1977 and March 1978 in Vienna. The total number of probands was divided into age groups, each comprising a range of 3 years. The average value with 1 SD. found over the whole age range was 48.3 +/- 25.75 nmol/l (i.e. 19.4 +/- 10.34 ng/ml). Somewhat higher levels were found in the age groups 3 to 6 and 6 to 9 years, with a slight decrease in the later age groups, but no significant differences were detected. The obtained values seem to represent the "normal" 25-OH-D3 serum levels of our population in the above-mentioned age range.

[Rickets prophylaxis by daily administration of vitamin D tablets (author's transl)]. / Rachitis-Tagesprophylaxe mit Vitamin-D-tabletten.

The efficiency of a daily vitamin D prophylaxis with tablets ("Laevovit D3"), containing 1000 I.U. cholecalciferol was studied in newborn babies (most of them "prematures") over a period of about 5 weeks. The blood-values of 25-hydroxycholecalciferol were taken as parameter and determined 1 week and 5 weeks after the start of vitamin D prophylaxis. The data obtained were--with very few exceptions-- in a range considered to be protective against development of vitamin D deficiency. No significant difference could be found comparing vitamin D prophylaxis with these "microtablets" vs. liquid vitamin D preparations.

Small-angle X-ray studies of the Fab and Fc fragments from the human immunoglobulin molecule Kol.

The conformation of the Fab and Fc fragments from the human immunoglobulin molecule Kol [IgI I, chi2gamma2, Gm(f)+] was studied by small-angle x-ray scattering in solution. The fragments were studied in 0.02 M Tris-HCl buffer. For the Fab fragment the radius of gyration was found to be 3.15 +/- 0.15 nm, the volume to be 75 +/- 8 nm3. For the Fc fragment the respective values were 3.15 +/- 0.15 nm for the radius of gyration and 91 +/- 8 nm3 for the volume. A large number of models were calculated for both fragments to find models which fit these data and have the same scattering curve. The models with the best agreement were compared with the models found for the crystalline state by crystal x-ray studies.

[Problems of distinction of normal, arteficial and pathological structures in mature human placental villi. III. Morphometric studies in rhesus incompatibility (author's transl)]. / Zur Abgrenzung normaler, artefizieller und pathologischer Strukturen in reifen menschlichen Plazentazotten. III. Morphometrische Untersuchungen bei Rhesus-Inkompatibilität.

Sections of human placental villi which were up to 80 micrometer in diameter were examined light microscopically and morphometrically. The villi were obtained by taking an aspiration biopsy of the attached placenta from 20 normal patients at term and from eight patients delivered at or before 37 weeks because of varying degrees of rhesus incompatibility. The distribution of three histological types of villi was determined. The intermediate villi from patients with erythroblastosis showed an increase in number and volume matching the severity of the disease. The intermediate villi also showed an increase in the amount of cytotrophoblasts, in the amount of materno-fetal diffusion surface area, in the thickness of syncytium, and in the number of Hofbauer cells. The terminal villi were not affected by erythroblastosis and the mature end villi showed a relative decrease in number. To obtain these results an optimal fixation technique was required.

Small-angle X-ray studies of the human immunoglobulin molecule Kol.

The conformation of the human immunoglobulin molecul Kol [IgG I, kappa2 gamma2, Gm(f)+] was studied by small-angle X-ray scattering in 0.15 M NaCl solution. The radius of gyration was found to be 5.84 +/- 0.04 nm, the volume 329 +/- 15 nm3 and the molecular weight 150 000 +/- 10 000. Information on the overall shape was obtained by comparing the experimental scattering curve with the calculated curves for various models. The models were obtained by arranging the models found for the Fab and Fc fragments of the same immunoglobulin molecule in a different manner. A model which fits all the date and the form of the experimental scattering curve is presented.

Small angle X-ray scattering study on bovine porphobilinogen synthase (5-aminolaevulinate dehydratase).

The quaternary structure of the native (zinc) porphobilinogen synthase (5-amino-laevulinate dehydratase) from bovine liver and its lead-substituted derivative is studied in solution by small angle X-ray scattering. In spite of the profound inhibitory effect of lead ions in the enzyme they do not produce a change in the quaternary structure detectable by small angle X-ray scattering. The most important molecular parameters of the native enzyme were found to be: radius of gyration Rg = 4.04 +/- 0.04 nm and maximum dimension Dmax = 12.0 +/- 0.5 nm. The corresponding values for the lead derivative are: Rg = 4.26 +/- 0.1 nm and Dmax = 12.5 +/- 0.5 nm. The quaternary structure of the enzyme in solution is described by a model, which fits the experimental scattering and distance distribution function.

[Hyalinosis cutis et mucosae--Urbach-Whiete syndrome. Review and case report]. / Hyalinosis cutis et mucosae--das Urbach-Whiete-Syndrom. Eine Ubersicht und Fallvorstellung.

We present the Urbach-Whiete-Syndrome as a rare cause of hoarseness in children. As such patients often present initially to the E.N.T. surgeon, we should like to draw attention to this autosomal recessive condition. Only symptomatic treatment is possible, and genetic counselling should be considered. The diagnosis of the disease should be as prompt as possible.

Structural changes in cellobiohydrolase I upon binding of a macromolecular ligand as evident by SAXS investigations.

Xylan from Rhodymenia palmata binds to the cellobiohydrolase I from Trichoderma reesei (CBH I) or its core protein, inhibiting their activity. Adsorption onto microcrystalline cellulose (Avicel) is reduced approximately 30% for intact CBH I and nearly 50% for the core, whereas the effects with cellobiose are negligible. Structural changes concomitant with this binding are studied in solution by small angle X-ray scattering. In the "tadpole" structure typical for the CBH I [Abuja et al., 1988] the lengthening of the tail part is the most salient observation when xylan is present which accounts for an increase in Dmax (18.0 to 22.0 nm) and radius of gyration (4.74 to 5.18 nm). When xylan binds to the core the radius of gyration remains nearly unchanged. Here a model can be constructed showing a xylan molecule on the surface of the core protein near the tail part.