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Eloise J. Pigott Warren Roberts Simon P. B. Ovenden Simone Rochfort David J. Bourne 《Metabolomics : Official journal of the Metabolomic Society》2012,8(4):634-642
Eight specimens of six known cultivars of Ricinus communis were investigated for differences in their metabolome that could be used to determine both provenance and cultivar. Seven replicates of three seeds per specimen were subjected to 1H NMR analysis, with the collected data further investigated using multivariate statistical analysis (OPLS-DA), resulting in class separations according to provenance. Analysis of loadings plots in addition to further chemical analysis of the extracts allowed for the identification of phenylalanine, ricinine, the N-demethyl and O-demethyl analogues of ricinine, and sucrose as important molecular markers for particular cultivars. To test the strength of the model, extracts generated from blinded specimens were used as a prediction set and were correctly classified according to provenance and cultivar. 相似文献
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Bourne DG Boyett HV Henderson ME Muirhead A Willis BL 《Applied and environmental microbiology》2008,74(3):883-888
A ciliate associated with the coral disease brown band (BrB) was identified as a new species belonging to the class Oligohymenophorea, subclass Scuticociliatia. The ciliates were characterized by the presence of large numbers of intracellular dinoflagellates and displayed an elongated, tube-shaped body structure. They had uniform ciliature, except for three distinct cilia in the caudal region, and were typically 200 to 400 microm in length and 20 to 50 microm in width. 相似文献
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John Westbrook Zukang Feng Shri Jain T. N. Bhat Narmada Thanki Veerasamy Ravichandran Gary L. Gilliland Wolfgang F. Bluhm Helge Weissig Douglas S. Greer Philip E. Bourne Helen M. Berman 《Nucleic acids research》2002,30(1):245-248
The Protein Data Bank (PDB; http://www.pdb.org/) is the single worldwide archive of structural data of biological macromolecules. This paper describes the progress that has been made in validating all data in the PDB archive and in releasing a uniform archive for the community. We have now produced a collection of mmCIF data files for the PDB archive (ftp://beta.rcsb.org/pub/pdb/uniformity/data/mmCIF/). A utility application that converts the mmCIF data files to the PDB format (called CIFTr) has also been released to provide support for existing software. 相似文献
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B R Conklin O Chabre Y H Wong A D Federman H R Bourne 《The Journal of biological chemistry》1992,267(1):31-34
Gq mediates hormonal stimulation of phosphoinositide-specific phospholipase C (PI-PLC). We mutated the alpha subunit of Gq (alpha q) to replace arginine 183 with cysteine. Mutations that substitute cysteine for the corresponding arginine residues of alpha s and alpha i2 constitutively activate their respective effector pathways, creating the gsp and gip2 oncogenes. Transient expression of alpha q-R183C in COS-7 and HEK-293 cells constitutively activates PI-PLC, but wild type (WT) alpha q does not. This suggests that the mutated arginines in alpha s, alpha i2, and alpha q share a common function in regulating the active state of these proteins and that the alpha q gene may serve as a target for oncogenic mutations in human tumors. In an attempt to develop an assay for receptor stimulation of recombinant alpha q, we co-expressed receptors with alpha q-WT. We found that the alpha 2-adrenoceptor stimulates PI-PLC activation in HEK-293 cells in a fashion that depends completely on co-expression of alpha q-WT. These findings create an experimental model, similar to that provided for alpha s by S49 cyc- cells, that should make it possible to analyze receptor and effector coupling by mutant alpha q against a null background. 相似文献