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231.
H Higashi K Ikuta S Ueda S Kato Y Hirabayashi M Matsumoto M Naiki 《Journal of biochemistry》1984,95(3):785-794
Heterophile, Hanganutziu-Deicher (HD) antigen-active N-glycolylneuraminic acid-containing glycosphingolipids (GSLs) were detected as tumor-associated foreign antigens of a Marek's disease lymphoma-derived cell line, MSB1, by enzyme-immunoassay with chicken antibody against N-glycolylneuraminyl-lactosylceramide (anti-NeuGc-LacCer). At least three species of HD antigen-active GSLs were detected by two-dimensional thin-layer chromatography (TLC) combined with enzyme-immunoassay. The reactivities of the GSLs with anti-NeuGc-LacCer, their behaviors on two-dimensional TLC and the results of an endo-beta-galactosidase digestion study indicated that these three GSLs were NeuGc-LacCer (NeuGc alpha 2-2Gal beta 1-4Glc-Cer), NeuGc-nLcOse4Cer (NeuGc alpha 2-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc-Cer) and NeuGc-nLcOse6Cer (NeuGc alpha 2-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc-Cer). 相似文献
232.
A kinetic model was devised for the hydrolysis and synthesis of maltose and isomaltose by two glucoamylases from Rhizopus niveus and Aspergillus niger, and the validity of the model was verified experimentally at 313 K and pH 5.0. For both enzymes, the formations of maltose and isomaltose from glucose were parallel reversible reactions, and glucosyl transfer between maltose and isomaltose was not observed. The enzymes catalyzed rapid hydrolysis and synthesis of maltose. Isomaltose was hydrolyzed and synthesized more slowly, but the level produced from glucose was much higher than that of maltose. These hydrolysis and condensation reactions were expressed well by the model. 相似文献
233.
Summary New cell lines, designated as ML-DmDl≈10, were established from dissociated imaginal discs ofDrosophila melanogaster. The culture medium was prepared by mixing in a 1:1 ratio Cross and Sang’s M3(BF) medium, supplemented with 10% heat inactivated
fetal bovine serum (FBS), with the supernatant of a primary embryonic cell culture made in the M3(BF) medium and supplementing
this mixture with insulin. One cell line was established in the medium containing larval hemolymph instead of the primary
culture supernatan, and another was established in fresh M3(BF) medium supplemented with insulin and FBS. In these mediums,
imaginal disc cells first formed aggregates and cellular vesicles within a few weeks followed by the proliferation of thin-layered
cells around them after about 1 mo. Ten cell lines have so far been established from two kinds of imaginal discs and disc
mixtures. The ploidy of these cell lines was predominantly diploid. Population doubling time was about 50 to 70 h at 3 to
10 mo. after initiation of the culture. When the cell aggregates formed in vitro were implanted in metamorphosing larvae,
they differentiated at high frequency into adult cuticular strutures in the early phase of the primary culture. This differentiation
of aggregates was also observed, though at low frequency, in a culture maintained by dilution-transfer for 6 to 15 mo. in
vitro. 相似文献
234.
The subcellular distribution of Ca2+/calmodulin-stimulated adenylate cyclase activity was studied in comparison with that of guanine nucleotide-stimulated cyclase activity. The distributions of these activities were similar among the crude fractions but differed among the purified subsynaptosomal fractions. The specific activity of Ca2+/calmodulin-stimulated cyclase was highest in a light synaptic membrane fraction, which has few, if any, postsynaptic densities, whereas that of guanine nucleotide-stimulated cyclase was highest in a heavier synaptic membrane fraction rich in postsynaptic densities. These results suggest that the Ca2+/calmodulin-stimulated cyclase has, at least in part, a different cellular or subcellular location than the guanine nucleotide-stimulated cyclase.Abbreviations used CaM
calmodulin
- GppNHp
guanosine 5-(,-imino) triphosphate 相似文献
235.
Journal of Plant Research - The vascular anatomy of seven genera of Magnoliaceae:Elmerrillia, Liriodendron, Magnolia, Manglietia, Michelia, Paramichelia andTalauma, was examined. Based on the... 相似文献
236.
237.
238.
M. Islam Khan M. K. Mathew T. Mazumdar D. Pain N. Surolia M. K. Das P. Balaram A. Surolia 《Journal of biosciences》1983,5(1):31-39
The binding ofRicinus communis agglutinin andAbrus agglutinin to 4-methylumbelliferyl β-D-galactopyranoside was studied by equilibrium dialysis, fluo-rescence quenching and fluorescence polarization. The number of binding sites and the association constant value obtained by fluorescence polarization for bothRicinus communis agglutinin andAbrus agglutinin are in close agreement with those obtained by the other methods. This indicates the potential of ligand-fluorescence polarization measurements in the investigation of lectin-sugar interactions. 相似文献
239.
Irwin J. Goldstein 《Journal of biosciences》1983,5(1):65-71
The physical-chemical and carbohydrate binding specificity ofGriffonia simplicifolia I (GS I) isolectins, one of the 4 lectins isolated fromGriffonia simplicifolia seeds, are described.Association constants for the binding of methyl α- and β-D-galactopyranoside and methyl 2-acetamido-2-deoxy-α-D-galactopyranoside to the A4, A2 B2 and B4 isolectins are reported.Precipitation reactions of theGriffonia simplicifolia isolectins with guaran and type B blood group substance are described.The hypothesis that subunit B is a precursor of subunit A, a process involving proteolytic cleavage of the B subunit, was tested by conducting structural studies on the 2 subunits. The results indicated that the A and B subunits are probably products of 2 separate but closely related, possibly contiguous genes. 相似文献
240.
The kinetics of haemolysis of rabbit erythrocytes byCroton tiglium lectin was studied as a function of concentration of the lectin and erythrocytes. The length of the prelytic period decreased with increasing lectin concentrations, indicating that the secondary events at the membrane which follow the binding of the lectin to cell surface carbohydrate receptors are accelerated at higher surface concentrations of the lectin. The rate or extent of haemolysis was not affected by the inclusion of ions like K+, Ca2+ and Mg2+ in the medium or by the substitution of ionic medium by a non-ionic medium. The inhibition of haemagglutination and haemolysis of rabbit red cells byCroton tiglium lectin by antilectin rabbit serum was observed. A possible mechanism of haemolysis by the lectin is discussed. 相似文献