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71.
Kurt W. Schmid Birgit Kunk Rudolf Kirchmair Martin T?tsch Werner B?cker Reiner Fischer-Colbrie 《The Histochemical journal》1995,27(6):473-481
Summary An antiserum raised against a synthetic peptide derived from the primary amino sequence of rat secretogranin II (chromogranin
C) was used for immunological (quantitative radioimmunoassay analysis) and immunohistochemical studies of normal human endocrine
and nervous tissues. This antibody recognized a novel and biologically active neuropeptide which was coined as secretoneurin.
In endocrine tissues, secretoneurin was mainly co-localized with chromogranin A and B with some exceptions (e.g., parathyroid
gland). Secretoneurin was demonstrated immunohistochemically in the adrenal medulla, thyroid C cells, TSH- and FSH/LH-produting
cells of the anterior pituitary, A and B cells of pancreatic islets, in endocrine cells of the gastrointestinal tract and
the bronchial mucosa, and the prostate. Immunoreactivity determined by radioimmunoassay analysis revealed high secretoneurin
levels in the anterior and posterior pituitary and lower levels in pancreatic and thyroid tissue. A strong secretoneurin immunoreactivity
was also found in ganglion cells of the submucdsal and myenteric plexus of the gastrointestinal tract, and in ganglionic cells
of dorsal root ganglia, peripheral nerves, and ganglion cells of the adrenal medulla. Thus, secretoneurin may serve as a useful
marker of gangliocytic/neuronal differentiation. 相似文献
72.
Jan Deussing Roth Wera Rommerskirch Winfried Wiederanders Bernd Figura von Kurt Christoph Peters 《Mammalian genome》1997,8(4):241-245
The mouse genes for the lysosomal cysteine proteinases cathepsin B, H, L, and S were mapped to Chromosomes (Chrs) 14, 9,
13, and 3, respectively. Two of the DNA probes used in this study detected an additional, independently segregating locus.
The cathepsin B-specific probe hybridized to a locus on Chr 2, and the cathepsin H probe to a locus on the X Chr. These loci
either correspond to pseudogenes or to cathepsin B- and cathepsin H-related genes. The four cysteine proteinases mapped in
this study lie within known regions of conserved synteny between mouse and human chromosomes, when compared with the corresponding
positions of their human homologs. Assuming that the genes of the cysteine proteinase gene family arose from a common ancestral
gene, our results suggest that these four cysteine proteinases had been dispersed over different chromosomes before separation
of mouse and human in evolution.
Received: 22 August 1996 / Accepted: 20 November 1996 相似文献
73.
74.
Maurizio Pellecchia Gerhard Wider Hideo Iwai Kurt Wüthrich 《Journal of biomolecular NMR》1997,10(2):193-197
A novel 2D NMR experiment, 2D HE(NE)HGHH, is presented for the assignment ofarginine side chain 1H and 15N resonances inuniformly 15N-labeled proteins. Correlations between1H, 1Hand 1H are established on the basis of3J(15N,1H) heteronuclear scalarcoupling constants, and sequence-specific assignments are obtained by overlapof these fragments with 1H chemical shiftsobtained by assignment procedures starting from the polypeptide backbone.Since guanidino protons exchange quite rapidly with the bulk water, the 2DHE(NE)HGHH pulse scheme has been optimized to avoid saturation and dephasingof the water magnetization during the course of the experiment. As anillustration, arginine side chain assignments are presented for two uniformly15N-labeled proteins of 7 and 23 kDa molecular weight. 相似文献
75.
DISGEO is a new implementation of a distance geometry algorithm which has been specialized for the calculation of macromolecular conformation from distance measurements obtained by two-dimensional nuclear Overhauser enhancement spectroscopy. The improvements include (1) a decomposition of the complete embedding process into two successive, more tractable calculations by the use of “substructures”, (2) a compact data structure for storing incomplete distance information on a structure, (3) a more efficient shortest-path algorithm for computing the triangle inequality limits on all distances from this information, (4) a new algorithm for selecting random metric spaces from within these limits, (5) the use of chirality constraints to obtain good covalent geometry without the use ofad hoc weights or excessive optimization. The utility of the resultant program with nuclear magnetic resonance data is demonstrated by embedding complete spatial structures for the protein basic pancreatic trypsin inhibitor vs all 508 intramolecular, interresidue proton-proton contacts shorter than 4.0 Å that were present in its crystal structure. The crystal structure could be reproduced from this data set to within 1.3 Å minimum root mean square coordinate difference between the backbone atoms. We conclude that the information potentially available from nuclear magnetic resonance experiments in solution is sufficient to define the spatial structure of small proteins. 相似文献
76.
Lun He Kurt J. Isselbacher Jack R. Wands Howard M. Goodman Chiaho Shih Andrea Quaroni 《In vitro cellular & developmental biology. Plant》1984,20(6):493-504
Summary A human hepatocellular carcinoma cell line (FOCUS—Friendship of China and United States) was derived from a patient with primary
hepatocellular carcinoma. This cell line has been in continuous culture over an 18-mo period. The morphological and ultrastructural
features of FOCUS are consistent with its neoplastic hepatocellular orgin. FOCUS cells contain aspartate aminotransferase
and glucose-6-phosphatase activity. In addition, α1-antitrypsin, fibrinogen, alpha fetoprotein, and carcinoembryonic antigens were detectble in the cytoplasm of the cultured
cells by immunochemical staining techniques. The karyotype of the FOCUS cell is human in origin and it contains human DNA
sequences as detected by molecular hybridization analysis. The FOCUS cells do not show evidence of density-dependent inhibition
of growth under confluent conditions. Repeated growth curves over an 18-mo period were identical, revealing a doubling time
of 42 to 48 h. The malignant potential of FOCUS cells was further demonstrated by their ability to lead to gross tumor formation
after subcutaneous infection into nude mice. From one of the solid tumors grown in nude mice, recultured cell lines have been
established and found to have properties identical to the original FOCUS cell line. This FOCUS cell line represents an additional
model for further investigation of tumor specific antigens and the relationship between hepatitis B virus (HBV) and hepatocellular
carcinoma. Preliminary molecular characterization has indicated the existence of integrated HBV sequences within the FOCUS
genome. 相似文献
77.
J.M. Gennity Nestor R. Bottino Ralph A. Zingaro Andrew E. Wheeler Kurt J. Irgolic 《Biochemical and biophysical research communications》1984,118(1):176-182
Axenic cultures of the green algae and red algae were grown in the presence of sublethal quantities of selenite. All purified lipids from both algae were found to contain bound selenium, except for saturated hydrocarbons. Of the lipids which contain selenium, carotenoid pigments contain the greatest concentrations. Lipid-associated selenium is not metabolically incorporated. The selenium is probably non-covalently bound to the lipids. 相似文献
78.
Kurt A. Santarius 《Planta》1984,161(6):555-561
Freezing of isolated spinach thylakoids in the presence of NaCl uncoupled photophosphorylation from electron flow and increased the permeability of the membranes to protons. Addition of ATP prior to freezing diminished membrane inactivation. On a molar basis, ATP was at least 100 times more effective in protecting thylakoids from freezing damage than low-molecularweight carbohydrates such as sucrose and glucose. The cryoprotective effectiveness of ATP was increased by Mg2+. In the absence of carbohydrates, preservation of thylakoids during freezing in 100 mM NaCl was saturated at about 1–2 mM ATP, but under these conditions membranes were not fully protected. However, in the presence of small amounts of sugars which did not significantly prevent thylakoid inactivation during freezing, ATP concentrations considerably lower than 0.5 mM caused nearly complete membrane protection. Neither ADP nor AMP could substitute for ATP. These findings indicate that cryoprotection by ATP cannot be explained by a colligative mechanism. It is suggested that ATP acts on the chloroplast coupling factor, either by modifying its conformation or by preventing its release from the membranes. The results are discussed in regard to freezing injury and resistance in vivo.Abbreviations CF1
chloroplast coupling factor
- Hepes
4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid
- PMS
phenazine methosulfate
- Tris
2-amino-2-(hydroxymethyl)-1,3-propandiol 相似文献
79.
Evidence for lysosomal enzyme recognition by human fibroblasts via a phosphorylated carbohydrate moiety 总被引:8,自引:8,他引:0
Kurt Ullrich Günther Mersmann Ernst Weber Kurt Von Figura 《The Biochemical journal》1978,170(3):643-650
Adsorptive endocytosis of five different lysosomal enzymes from various human and non-human sources was susceptible to inhibition by mannose and l-fucose, methyl α-d-mannoside, α-anomeric p-nitrophenyl glycosides of mannose and l-fucose, mannose 6-phosphate and fructose 1-phosphate. A few exceptions from this general scheme were observed for particular enzymes, particularly for β-glucuronidase from human urine. The inhibition of α-N-acetylglucosaminidase endocytosis by mannose, p-nitrophenyl α-d-mannoside and mannose 6-phosphate was shown to be competitive. The loss of endocytosis after alkaline phosphatase treatment of lysosomal enzymes supports the hypothesis that the phosphorylated sugars compete with a phosphorylated carbohydrate on the enzymes for binding to the cell-surface receptors [Kaplan, Achord & Sly (1977) Proc. Natl. Acad. Sci. U.S.A. 74, 2026–2030]. Endocytosis of `low-uptake' forms of α-N-acetylglucosaminidase and α-mannosidase was likewise susceptible to inhibition by sugar phosphates and by alkaline phosphatase treatment, suggesting that `low-uptake' forms are either contaminated with `high-uptake' forms or are internalized via the same route as `high-uptake' forms. The existence of an alternative route for adsorptive endocytosis of lysosomal enzymes is indicated by the unaffected adsorptive endocytosis of rat liver β-glucuronidase in the presence of phosphorylated sugars and after treatment with alkaline phosphatase. 相似文献
80.
Dr. Heidelinde Dürnberger Kurt Pohlhammer Gerhard Weinbörmair 《Cell and tissue research》1978,187(3):489-494
Summary Ovariectomy, performed immediately after the final hatch, caused a reduction of stainable (neurosecretory?) material in the paramedial neurosecretory cells (PNC) (A-type) of the suboesophageal ganglion in 10 day-old females of Teleogryllus commodus (Walk.). A concomitant increase in nuclear volume and in the incorporation of 35S-cysteine indicates increased synthesis of neurosecretory material. From these findings it is concluded that more stainable material is secreted in the cerebral neurohaemal organ after Ovariectomy. A functional relationship between the PNC and the ovaries is suggested. 相似文献