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1.
ESyPred3D: Prediction of proteins 3D structures   总被引:1,自引:0,他引:1  
MOTIVATION: Homology or comparative modeling is currently the most accurate method to predict the three-dimensional structure of proteins. It generally consists in four steps: (1) databanks searching to identify the structural homolog, (2) target-template alignment, (3) model building and optimization, and (4) model evaluation. The target-template alignment step is generally accepted as the most critical step in homology modeling. RESULTS: We present here ESyPred3D, a new automated homology modeling program. The method gets benefit of the increased alignment performances of a new alignment strategy. Alignments are obtained by combining, weighting and screening the results of several multiple alignment programs. The final three-dimensional structure is build using the modeling package MODELLER. ESyPred3D was tested on 13 targets in the CASP4 experiment (Critical Assessment of Techniques for Proteins Structural Prediction). Our alignment strategy obtains better results compared to PSI-BLAST alignments and ESyPred3D alignments are among the most accurate compared to those of participants having used the same template. AVAILABILITY: ESyPred3D is available through its web site at http://www.fundp.ac.be/urbm/bioinfo/esypred/ CONTACT: christophe.lambert@fundp.ac.be; http://www.fundp.ac.be/~lambertc  相似文献   

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SUMMARY: Voro3D is an original easy-to-use tool, which provides a brand new point of view on protein structures through the three-dimensional (3D) Voronoi tessellations. To construct the Voronoi cells associated with each amino acid by a number of different tessellation methods, Voro3D uses a protein structure file in the PDB format as an input. After calculation, different structural properties of interest like secondary structures assignment, environment accessibility and exact contact matrices can be derived without any geometrical cut-off. Voro3D provides also a visualization of these tessellations superimposed on the associated protein structure, from which it is possible to model a polygonal protein surface using a model solvent or to quantify, for instance, the contact areas between a protein and a ligand. AVAILABILITY: The software executable file for PC using Windows 98, 2000, NT, XP can be freely downloaded at http://www.lmcp.jussieu.fr/~mornon/voronoi.html CONTACT: franck.dupuis@sanofi-aventis.com; jean-paul-mornon@imcp.jussieu.fr.  相似文献   

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Motif3D is a web-based protein structure viewer designed to allow sequence motifs, and in particular those contained in the fingerprints of the PRINTS database, to be visualised on three-dimensional (3D) structures. Additional functionality is provided for the rhodopsin-like G protein-coupled receptors, enabling fingerprint motifs of any of the receptors in this family to be mapped onto the single structure available, that of bovine rhodopsin. Motif3D can be used via the web interface available at: http://www.bioinf.man.ac.uk/dbbrowser/motif3d/motif3d.html.  相似文献   

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Anhydrolevuglandin D2 (AnLGD2), which is produced from PGH2 by a water-induced rearrangement and subsequent dehydration, is uterotonic. However, increasing concentrations caused decreased responses of the uterine horns. AnLGD2 inhibited responses of uteri to stimulation by specific prostaglandins. PGF2 alpha was inhibited at an AnLGD2:PGF2 alpha ratio of 0.05:1 with 5 to 25 pg/ml concentrations of PGF2 alpha. The response to PGD2 was inhibited at an AnLGD2:PGD2 ratio of 0.05:1 with PGD2 concentrations of 5 to 75 pg/ml. In contrast, the uterotonic effects of PGE2 were not inhibited by AnLGD2. When AnLGD2 was added to baths with contracting uteri it inhibited contractions less if the exposure period was 5 min than if it was 10 min. The longer exposure times produced prolonged inhibition of contractile activity with bath concentrations of AnLGD2 as little as 2.5 pg/ml.  相似文献   

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We studied determinants of Vitamin D in serum of 67 female health care workers (aged 25–60 years), including age, body mass index, physical activity, and shift work. Overall, vitamin D levels were low, ranging from 6 to 51 ng/mL (median: 20 ng/mL). Lower serum levels were found in samples drawn in winter and spring and in obese subjects. Shift work had only small effects on vitamin D levels.

The high prevalence of vitamin D undersupply is in line with observations from the German general population. Vitamin D supply particularly in winter and spring should be ensured to avoid health problems.  相似文献   


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MOTIVATION: Protein structure comparison is a fundamental problem in structural biology and bioinformatics. Two-dimensional maps of distances between residues in the structure contain sufficient information to restore the 3D representation, while maps of contacts reveal characteristic patterns of interactions between secondary and super-secondary structures and are very attractive for visual analysis. The overlap of 2D maps of two structures can be easily calculated, providing a sensitive measure of protein structure similarity. PROTMAP2D is a software tool for calculation of contact and distance maps based on user-defined criteria, quantitative comparison of pairs or series of contact maps (e.g. alternative models of the same protein, model versus native structure, different trajectories from molecular dynamics simulations, etc.) and visualization of the results. AVAILABILITY: PROTMAP2D for Windows / Linux / MacOSX is freely available for academic users from http://genesilico.pl/protmap2d.htm  相似文献   

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Androgen-dependent signaling regulates the growth of the fingers on the human hand during embryogenesis. A higher androgen load results in lower 2D:4D (second digit to fourth digit) ratio values. Prenatal androgen exposure also impacts brain development. 2D:4D values are usually lower in males and are viewed as a proxy of male brain organization. Here, we quantified video gaming behavior in young males. We found lower mean 2D:4D values in subjects who were classified according to the CSAS-II as having at-risk/addicted behavior (n = 27) compared with individuals with unproblematic video gaming behavior (n = 27). Thus, prenatal androgen exposure and a hyper-male brain organization, as represented by low 2D:4D values, are associated with problematic video gaming behavior. These results may be used to improve the diagnosis, prediction, and prevention of video game addiction.  相似文献   

11.
BACKGROUND: Inadequate photosynthesis or oral intake of Vitamin D are associated with high incidence rates of colorectal cancer, but the dose-response relationship has not been adequately studied. METHODS: Dose-response gradients from observational studies of Vitamin D intake and serum 25-hydroxyvitamin D were plotted as trend lines. The point on each linear trend line corresponding to an odds ratio of 0.50 provided the prediagnostic Vitamin D intake or 25-hydroxyvitamin D concentration associated with 50% lower risk compared to <100IU/day Vitamin D or <13ng/ml serum 25-hydroxyvitamin D. Medians of these values were determined. RESULTS: Overall, individuals with >or=1000IU/day oral Vitamin D (p<0.0001) or >or=33ng/ml (82nmol/l) serum 25-hydroxyvitamin D (p<0.01) had 50% lower incidence of colorectal cancer compared to reference values. CONCLUSIONS: Intake of 1000IU/day of Vitamin D, half the safe upper intake established by the National Academy of Sciences, was associated with 50% lower risk. Serum 25-hydroxyvitamin D of 33ng/ml, which is known to be safe, also was associated with 50% lower risk. Prompt public health action is needed to increase intake of Vitamin D(3) to 1000IU/day, and to raise 25-hydroxyvitamin D by encouraging a modest duration of sunlight exposure.  相似文献   

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Summary: Traditional two-dimensional (2D) software programsfor drawing pedigrees are limited when dealing with extendedpedigrees. In successive generations, the number of individualsgrows exponentially, leading to an unworkable amount of spacerequired in the horizontal direction for 2D displays. In addition,it is not always possible to place closely related individualsnear each other due to the lack of space in 2Ds. To addressthese issues we have developed three-dimensional (3D) pedigreedrawing techniques to enable clearer visualization of extendedpedigrees. Currently no other methods are available for displayingextended pedigrees in 3Ds. We have made freely available a softwaretool—‘Celestial3D’—that implements thesenovel techniques. Availability: Freely available to non-commercial users Contact: celestial3d{at}genepi.org.au Supplementary information: www.genepi.org.au/celestial3d Associate Editor: Martin Bishop 1A more extensive list of software tools appears in the SupplementaryMaterial.  相似文献   

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《Cell reports》2023,42(1):112008
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SUMMARY: SWEET is a WWW-based tool which rapidly converts the commonly used carbohydrate sequence information directly into a preliminary but reliable 3D model which can be visualised and written to files in several ways. AVAILABILITY: SWEET is accessible via the Internet at http://www.dkfz-heidelberg.de/spec/. CONTACT: a. bohne@dkfz-heidelberg.de or w.vonderlieth@ dkfz-heidelberg.de SUPPLEMENTARY INFORMATION: The current version of SWEET generates only one conformation out of a manifold. Several authors have analysed possible conformations of high-mannose N-linked glycans using a combination of NMR methods and computational approaches showing that such molecules are rather flexible populating normally several conformations for each glycosidic linkage. The displayed model exhibits for all glycosidic linkages a conformation which is in accordance with the reported variations of Phi, psi and omega values for specific linkage (see http://www.dkfz-heidelberg. de/spec/sweet2/doc/input/sba_example.html).  相似文献   

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《Cell metabolism》2022,34(9):1394-1409.e4
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18.
Circulating 25-hydroxyvitamin D [25(OH)D] is generally considered the means by which we define nutritional vitamin D status. There is much debate, however, with respect to what a healthy minimum level of circulation 25(OH)D should be. Recent data using various biomarkers such as intact parathyroid hormone (PTH), intestinal calcium absorption, and skeletal density measurements suggest this minimum level to be 80 nmol (32 ng/mL). Surprisingly, the relationship between circulating vitamin D3 and its metabolic product—25(OH)D3 has not been studied. We investigated this relationship in two separate populations: the first, individuals from Hawaii who received significant sun exposure; the second, subjects from a lactation study who received up to 6400 IU vitamin D3/day for 6 months.

Results (1) the relationship between circulating vitamin D3 and 25(OH)D in both groups was not linear, but appeared saturable and controlled; (2) optimal nutritional vitamin D status appeared to occur when molar ratios of circulating vitamin D3 and 25(OH)D exceeded 0.3; at this point, the Vmax of the 25-hydroxylase appeared to be achieved. This was achieved when circulating 25(OH)D exceeded 100 nmol.

We hypothesize that as humans live today, the 25-hydroxylase operates well below its Vmax because of chronic substrate deficiency, namely vitamin D3. When humans are sun (or dietary) replete, the vitamin D endocrine system will function in a fashion as do these other steroid synthetic pathways, not limited by substrate. Thus, the relationship between circulating vitamin D and 25(OH)D may represent what “normal” vitamin D status should be.  相似文献   


19.
SUMMARY: We describe the application of distance geometry methods to the three-dimensional visualization of sequence relationships, with examples for mumps virus SH gene cDNA and prion protein sequences. Sequence-sequence distance measures may be obtained from either a multiple sequence alignment or from sets of pairwise alignments. AVAILABILITY: C/Perl code and HTML/VRML files from http://www.nibsc.ac.uk/dg3dseq/  相似文献   

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