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71.
J.Michael Conlon Nicolas Chartrel Jerome Leprince Charles Suaudeau Jean Costentin Hubert Vaudry 《Peptides》1996,17(8):1291-1296
A peptide derived from the posttranslational processing of proenkephalin A was isolated from an extract of the brain of the European green frog Rana ridibunda and its primary structure established as: Tyr-Gly-Gly-Phe-Met-Arg-Arg-Val-Gly-Arg10-Pro-Glu-Trp-Trp-Gln-Asp-Tyr-Gln-Lys-Arg20-Tyr-Gly-Gly-Phe-Met. The structure was confirmed by chemical synthesis. The peptide represents an amphibian equivalent of bovine adrenal peptide E [preproenkephalin A (206–230)-peptide] but the sequence contains two amino acid substitutions (Met15 → Gln and Leu25 → Met) compared with the mammalian peptide. The data support previous hypotheses that the Leu-enkephalin sequence is not present in preproenkephalin A of amphibians. Intracerebroventricular injections of frog peptide E (10 and 100 ng) in mice had no significant effect on horizontal locomotor activity. The peptide, in doses up to 1 μg, had no effect on latency of escape jumping in the hot plate test and the peptide (100 ng) did not modify responses (paw licking, rearing, and escape jumping) in morphine-treated mice. 相似文献
72.
In the short day plant Chenopodium rubrum and the long day plant Nicotiana tabacum cv. Havana 425, adenylate kinase (EC 2.7.4.3) occurs as a family of isoforms, with at least two members localized in the chloroplast representing the main isoforms. In this work, isoforms were separated by anion exchange chromatography and relative isoform activities were compared between vegetative plants and plants induced to flowering. In both species examined, a light regime leading to floral induction resulted in a significant decrease in the activity of one chloroplast isoform. This decrease modified considerably the relative distribution of isoform activities, especially that between the two chloroplast activities. 相似文献
73.
A protein binds the selenocysteine insertion element in the 3'-UTR of mammalian selenoprotein mRNAs. 总被引:6,自引:0,他引:6
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Several gene products are involved in co-translational insertion of selenocysteine by the tRNA(Sec). In addition, a stem-loop structure in the mRNAs coding for selenoproteins is essential to mediate the selection of the proper selenocysteine UGA codon. Interestingly, in eukaryotic selenoprotein mRNAs, this stem-loop structure, the selenocysteine insertion sequence (SECIS) element, resides in the 3'-untranslated region, far downstream of the UGA codon. In view of unravelling the underlying complex mechanism, we have attempted to detect RNA-binding proteins with specificity for the SECIS element. Using mobility shift assays, we could show that a protein, present in different types of mammalian cell extracts, possesses the capacity of binding the SECIS element of the selenoprotein glutathione peroxidase (GPx) mRNA. We have termed this protein SBP, for Secis Binding Protein. Competition experiments attested that the binding is highly specific and UV cross-linking indicated that the protein has an apparent molecular weight in the range of 60-65 kDa. Finally, some data suggest that the SECIS elements in the mRNAs of GPx and another selenoprotein, type I iodothyronine 5' deiodinase, recognize the same SBP protein. This constitutes the first report of the existence of a 3' UTR binding protein possibly involved in the eukaryotic selenocysteine insertion mechanism. 相似文献
74.
Ingo Marenholz Armin Volz Andreas Ziegler Angela Davies Ioannis Ragoussis Bernhard P. Korge Dietmar Mischke 《Genomics》1996,37(3):295
The epidermal differentiation complex (EDC) unites a remarkable number of structurally, functionally, and evolutionarily related genes that play an important role in terminal differentiation of the human epidermis. It is localized within 2.05 Mb of region q21 on human chromosome 1. We have identified and characterized 24 yeast artificial chromosome (YAC) clones by mapping individual EDC genes, sequence-tagged site (STS) markers (D1S305, D1S442, D1S498, D1S1664), and 10 new region-specific probes (D1S3619–D1S3628). Here we present a contig that covers about 6 Mb of 1q21 including the entire EDC. Fluorescencein situhybridization on metaphase chromosomes with two YACs flanking the EDC determined its chromosomal orientation and established, in conjunction with physical mapping results, the following order of genes and STSs: 1cen–D1S442–D1S498–S100A10–THH–FLG–D1S1664–IVL–SPRR3–SPRR1–SPRR2–LOR–S100A9–S100A8–S100A7–S100A6–S100A5–S100A4–S100A3–S100A2–S100A1–D1S305–1qtel. These integrated physical, cytogenetic, and genetic mapping data will be useful for linkage analyses of diseases associated with region 1q21 and for the identification of novel genes and regulatory elements in the EDC. 相似文献
75.
Pretreatment of Parsley (Petroselinum crispum L.) Suspension Cultures with Methyl Jasmonate Enhances Elicitation of Activated Oxygen Species 总被引:6,自引:6,他引:0
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Suspension-cultured cells of parsley (Petroselinum crispum L.) were used to demonstrate an influence of jasmonic acid methyl ester (JAME) on the elicitation of activated oxygen species. Preincubation of the cell cultures for 1 d with JAME greatly enhanced the subsequent induction by an elicitor preparation from cell walls of Phytophtora megasperma f. sp. glycinea (Pmg elicitor) and by the polycation chitosan. Shorter preincubation times with JAME were less efficient, and the effect was saturated at about 5 [mu]M JAME. Treatment of the crude Pmg elicitor with trypsin abolished induction of activated oxygen species, an effect similar to that seen with elicitation of coumarin secretion. These results suggest that JAME conditioned the parsley suspension cells in a time-dependent manner to become more responsive to elicitation, reminiscent of developmental effects caused by JAME in whole plants. It is interesting that pretreatment of the parsley cultures with 2,6-dichloroisonicotinic and 5-chlorosalicylic acid only slightly enhanced the elicitation of activated oxygen species, whereas these substances greatly enhanced the elicitation of coumarin secretion. Therefore, these presumed inducers of systemic acquired resistance exhibit a specificity different from JAME. 相似文献
76.
Bienvenu Thierry Hubert Dominique Fonknechten Nuria Dusser Daniel Kaplan Jean Claude Beldjord Cherif 《Human genetics》1994,94(1):65-68
Human Genetics - Cystic fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR). Analysis of DNA from a pancreatic sufficient patient by means of... 相似文献
77.
Rinkel Monique Hubert Jean-Claude Roux Brigitte Lett Marie-Claire 《Current microbiology》1994,29(5):249-254
AKlebsiella pneumoniae strain having mobilization helper potential has been isolated from the river Rhine. Analysis of the transconjugants resulting from the mobilization of nonconjugative pBR-type plasmids and RSF1010 derivatives showed that the transfer-helper capacity of theK. pneumoniae strain is related to the presence of a Tn3-like transposable element, Tn5403. This element has been identified and localized in a plasmid. 相似文献
78.
Fourier transform infrared (FTIR) spectroscopy for identifying Lactobacillus species 总被引:3,自引:0,他引:3
Abstract Fourier Transform infrared (FTIR) spectroscopy can be used to identify microorganisms. This study describes the influence of culture conditions on FTIR spectra and the discrimination of Lactobacillus species found in breweries. Fifty three Lactobacillus strains were analysed by FTIR spectroscopy and identification at the species level was correct for 94% of the strains, and at the strain level for 91% of the strains. 相似文献
79.
Bert Weckhuysen Luc Vriens Hubert Verachtert 《Applied microbiology and biotechnology》1993,39(3):395-399
Butanal is one of the odorous compounds produced in the animal-rendering and food-processing industries and also in sewage-treatment plants. It shows the necessity for complementing such plants with systems for off-gas treatment. Biofiltration using simple packing material was tested for the removal of butanal. Excellent results were obtained when the filters operated at optimal humidity and were supplemented with inorganic nutrients. Without nutrients, butyric acid was detected in the effluent gas, which may explain the lower efficiency of filters without nutrients. Under optimal conditions an elimination of around 90 g·m–3·h–1 was reached. 相似文献
80.
L. Pradier E. Heuillet J. P. Hubert M. Laville S. Le Guern A. Doble 《Journal of neurochemistry》1993,61(5):1850-1858
Abstract— In the human astrocytoma cell line U 373 MG, application of substance P (SP) leads to a transient increase in cytosolic calcium concentration and to a biphasic current response in voltage-clamped cells. Using these two functional assays we have characterized pharmacologically the SP response in U 373 MG cells. SP and [l -Pro9]SP displayed high potencies in both assays with EC50values of 2.5 ± 10?9M and 1 ± 10?9M on calcium responses and 110?9M and 510?9M on ion current responses, respectively. The high potency of SP and [l -Pro9]SP as well as the low potency of [Lys5,MeLeu9,N-Leu10]neurokinin A(4-10) and the inactivity of senktide demonstrate the NK1-type pharmacology of these responses. Furthermore, the NK1 antagonists (±)-CP 96,345, its chloro analogue, (±)-cis-3-(2-chlorobenzylamino)-2-benz-hydrylquinuclidine, and RP 67580 were potent antagonists of both SP responses. For the calcium mobilization induced by SP (1 (10?7M), the IC50 values for the three antagonists were 4 ± 10?10M, 4 ± 10?9M, and 9 ± 10?9M, respectively, whereas on the current response evoked by SP 10?8M), the IC50 values were 8 ± 10?9M, 2.4 ± 10?8M, and 1.2 10?7M, respectively. Despite differences in the absolute IC50 values obtained with both techniques, the relative potencies of the three antagonists correlate fairly well. The U 373 MG cell line provides a useful model system for studies of the pharmacology of the human NK1receptor and its transduction mechanisms at the level of second messengers and modulation of ion currents. 相似文献