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M. H. Nielsen L. Bastholm S. Chatterjee J. Koga B. Norrild 《Histochemistry and cell biology》1989,92(2):89-93
Summary The mechanism of intracellular maturation and sorting of herpes simplex virus type I glycoproteins is not known in details. To elucidate the intracellular sorting of viral glycoproteins and their possible interaction with the cytoskeleton, a method for simultaneous immunogold staining of three antigens in ultrathin cryosections is described. Each antigen is stained by an indirect technique using mouse monoclonal IgG as first layer, rabbit antimouse IgG as second and gold-conjugated goat anti-rabbit IgG as third layer antibody. After each staining cycle the paraformaldehyde vapour at 80° C for 30 min. This destroys the free antigen combining sites of the second and the third layer IgG and abolish contaminating staining. Simultaneous triple-staining is documented with three mouse monoclonal antisera specific for 1) herpes simplex virus type 1 glycoprotein C, 2) glycoprotein D and 3) - and -tubulin as primary antibodies. Labelling for virus glycoproteins was found in some Golgi vesicles and close to the cytoplasmic microtubules as well as on the cell surface and on intracytoplasmic and extracellular virus particles.Presented in part at the 9th European Congress on Electron Microscopy, York, England, September 4–9, 1988 相似文献
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Further characterization and immunochemical studies on the carbohydrate specificity of jackfruit (Artocarpus integrifolia) lectin 总被引:12,自引:0,他引:12
The lectin from jackfruit (Artocarpus integrifolia) seeds has been purified by Rivanol (6,9-diamino-2-ethoxyacridine lactate) treatment. The specific activity, molecular weights of parent lectin and its subunit, its glycoprotein nature, and hemagglutination-inhibition assays suggest that this preparation is identical to that obtained by affinity chromatography on melibiose-agarose adsorbent (Ahmed, H., and Chatterjee, B. P. (1986) in Lectins, Biology, Biochemistry, Clinical Biochemistry (B?g-Hansen, T. C., and van Driessche, E., eds) Vol. 5, pp. 125-133, Walter de Gruyter, New York). The lectin strongly agglutinates human and several animal erythrocytes. The lectin contains five isolectins of pI values 7.1, 6.85, 5.5, 5.3, and 5.1. It is thermally stable and loses its activity above 75 degrees C. The hemagglutinating activity remains unchanged in the presence of bivalent cations viz., Ca2+, Mg2+, Mn2+, etc. It is a metalloprotein. The lectin retains its activity by dialysis with acetic acid followed by EDTA. It agglutinates Ehrlich ascites cells. Equilibrium dialysis of lectin with melibiose and quenching of fluorescence of 4-methylumbelliferyl-alpha-D-galactopyranoside by the lectin show that homotetrameric jackfruit lectin has two sugar-binding sites. The lectin precipitates well several galactomannans and glycoproteins having terminal D-Gal-alpha-(1----6)- or D-Gal-beta-(1----3)-D-GalNAc residues. It hardly or does not precipitate polysaccharides having terminal D-Gal-alpha-(1----3) residues. Quantitative precipitin-inhibition studies using various haptens suggest that the -OCH2- group at C-1 and -OH groups at C-4 and partially at C-6 in the alpha-glycoside of D-galactose configuration are important for lectin-sugar interaction. 相似文献
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Bioaccumulation of nickel and vanadium in the tissues of the liver, kidney, gill, and intestine has been studied following 4 days and 30 days of exposure at sublethal concentrations of nickel and vanadium compounds in the catfish Clarias batrachus. Nickel and vanadium have been found to accumulate in all four tissues observed. High concentrations of nickel and vanadium have been found in the order kidney greater than gill greater than liver greater than intestine during the 4 days and 30 days treatment. A dose-response effect was seen, as the concentration of metals in the tissues increased with concentration and exposure time. The effect on bioaccumulation in the specific tissue provides a better basis for monitoring exposures than whole-body analysis. 相似文献
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Catalase plays a major role in the protection of tissues from toxic effects of H2O2 and partially reduced oxygen species. In the present study catalase was extracted and purified 330-fold from goat lung by acetone fractionation and successive chromatographies on DEAE-cellulose, Sephadex G-200, Blue Sepharose CL-6B and Ultrogel AcA-34. The purified enzyme was almost homogeneous as judged by polyacrylamide gel electrophoresis and FPLC. The molecular weight and Stokes' radius of the purified enzyme were 339 kDa and 127±2 Å. The enzyme had 11 sulfhydryl groups and 15 tryptophan groups per mol of the enzyme. A broad pH optimum in the range 5.2 to 7.8 was obtained. Sulfhydryl group binding agents, thiol reagents and N-Bromosuccinimide inhibited the enzyme activity. The kinetic data show no cooperativity between the substrate binding sites. Tryptophan, indole acetic acid, cysteine, formaldehyde and sodium azide inhibited the enzyme non-competitively with Ki values of 1.5, 1.6, 6.7, 0.55 and 0.0017 mM, respectively. 相似文献
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Controlling certain diseases using peptide drugs has remarkably increased in the past two decades. In this regard, a generic formulation is an upfront solution to fulfill market demands. Ganirelix, a leading peptide active pharmaceutical ingredient (API) primarily used as a gonadotropin-releasing hormone antagonist (GnRH), has established a potential market value worldwide. But its generic formulation mandates detailed impurity profiles from a synthetic source and contemplates the sameness of a reference-listed drug (RLD). Post-chemical synthesis and processing of Ganirelix, some commercial sources have revealed two new potential impurities among many known, which show the deletion of an ethyl group from the hArg(Et)2 residue at the sixth and eighth positions, named des-ethyl-Ganirelix. These impurities are unprecedented in traditional peptide chemistry, and such monoethylated-hArg building blocks are not easily accessible commercially to synthesize these two impurities. Here, we have outlined the synthesis, purification, and enantiomeric purity characterization of the amino acids and their incorporation in the Ganirelix peptide sequence to synthesize these potential peptide impurities. This methodology will enable the convenient synthesis of side-chain substituted Arg and hArg derivatives in peptide drug discovery platforms. 相似文献
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