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The G antigen is one of the erythrocyte membrane Rh antigens. The amount of Rh antigen present on the red blood cell is about 10(-15) g and radioactive labeling of membrane proteins is a useful method for its identification and characterization. In this paper, we compare 4 labeling techniques. Using a human monoclonal anti-Rh(G) antibody and an immunofixation technique, we located the G antigen on a polypeptide of an average molecular weight of 28,000 Da. 相似文献
54.
Lipopolysaccharides (LPS) were extracted by hot phenol-water from five strains each of Azospirillum lipoferum and Azospirillum brasilense. Rhamnose, glucose, glucosamine and 3-deoxy-d-mannooctulosonic acid were comon sugar constituents of all LPS preparations. 2-O-Mefucose, 3-O-Me-fucose, 3-O-Me-rhamnose and 2-O-Megalactose were found in LPSs of some A. brasilense strains. Fatty acid spectra from all LPSs studied were almost identical with predominance of 3-hydroxymyristic and 3-hydroxypalmitic acids. 3-Hydroxypalmitic acid was the only amide-linked fatty acid. Lipopolysaccharides isolated from A. brasilense showed higher heterogeneity in sugar composition than those from A. lipoferum.Abbreviations glc
gas liquid chromatography
- ms
mass spectrometry
- LPS
lipopolysaccharide
- dOclA
3-deoxy-d-mannooctulosonic acid
- 3-OH-16:0
3-hydroxypalmitic acid
- nir-
nitrite reductase negative
- nir+
nitrite reductase positive 相似文献
55.
J. Sianoudis A. C. Küsel A. Mayer L. H. Grimme D. Leibfritz 《Archives of microbiology》1987,147(1):25-29
P-31 NMR investigations were performed with the green alga Chlorella fusca under anaerobic conditions in the dark and in the light.In spectra of cells in the dark the signal of intracellular, nonvacuolar Pi indicates a pH in its chemical environment of 7.0–7.2. Upon illumination this signal looses intensity and shifts to lower field, corresponding to a pH of 7.7. Further downfield no other signal that could be attributed to a Pi-pool in more alkaline environment was detected. By the use of 2-deoxyglucose-6-phosphate as an indicator of cytoplasmic pH, this Pi-signal was assigned to the cytoplasm. The pH increase in the cytoplasm upon transfer of cells from the dark to the light is the same as that previously observed upon transfer of cells from anaerobic to aerobic conditions.In cells performing only cyclic photophosphorylation the cytoplasmic pH is lower than in photosynthesizing cells but still 0.2 pH units higher than in the cells in the dark. The reasons for the missing of a signal of stromal Pi and for the difference in cytoplasmic pH in photosynthesizing cells and those capable only of cyclic photophosphorylation are discussed.Non-standard abbreviations 2dG
2-Deoxyglucose
- dG-6-P
2-deoxyglucose-6-phosphate
- DCMU
3,4-dichlorophenyl-dimethylurea
- MOPSO
3-(N-morpholino)-2-hydroxypropane sulfonic acid
- P-31 NMR
P-31 nuclear magnetic resonance 相似文献
56.
Philippe Lejeune Philippe Bertin Corinne Walon Karine Willemot Charles Colson Antoine Danchin 《Molecular & general genetics : MGG》1989,218(2):361-363
Summary Spontaneous mutants of Escherichia coli K12 displaying an increased level of the kanamycin resistance conferred by plasmid pGR71 were selected. Several mutants obtained in this way apparently carry large chromosomal deletions extending into galU and/or bglY (27 min). This positive selection of deletions allowed detection of a new locus located between galU and bglY. Deletions of this locus are responsible for increased resistance to kanamycin (Irk), decreased resistance to l-serine in minimal medium (Drs) and decreased resistance to chloramphenicol (Drc) when a cat gene is present in the bacteria. 相似文献
57.
R P Bolande D C Mayer 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1989,191(4):387-390
An IgM fraction of human serum was isolated and purified. A portion of this fraction firmly attaches to L cells' surfaces, which sensitizes these cells to the lytic action of low concentrations of serum C. It contains the natural cytotoxic "antibody" to L cells. 相似文献
58.
Ubiquitin-protein conjugates accumulate in the lysosomal system of fibroblasts treated with cysteine proteinase inhibitors. 总被引:2,自引:0,他引:2 下载免费PDF全文
F J Doherty N U Osborn J A Wassell P E Heggie L Laszlo R J Mayer 《The Biochemical journal》1989,263(1):47-55
Mouse fibroblasts (3T3-L1 cells) accumulate detergent- and salt-insoluble aggregates of proteins conjugated to ubiquitin when incubated in the presence of inhibitors of lysosomal cysteine cathepsins, including E-64. These ubiquitin-protein conjugates co-fractionate with lysosomes on density gradients and are found in multivesicular dense bodies which by electron microscopy appear to be engaged in microautophagy. Both E-64 and ammonium chloride increase the intracellular concentration of free ubiquitin, but only E-64 leads to the formation of insoluble lysosomal ubiquitin-protein conjugates. The results are discussed in relation to the possible intracellular roles of ubiquitin conjugation. 相似文献
59.
Anne Izard Gérard Goma Philippe Soucaille 《Applied microbiology and biotechnology》1989,31(2):179-183
Summary The inhibitory effect of various alkanols, benzyl alcohol and phenethyl alcohol on the growth rate of Clostridium acetobutylicum ATCC 824 was investigated. Inhibition of cell growth was studied by treating cultures with varied concentrations of alcohols. There was a threshold concentration above which growth inhibition occurred. The degree of inhibition was a linear function of the alcohol concentration used. The natural logarithm of the inhibition constant was shown to be: (1) a linear function of the chain length of the alkanols, (2) a linear function of the natural logarithm of the octanol/water partition coefficient for both aliphatic and cyclic alcohols. 相似文献
60.
A. C. Kuesel W. Kuhn J. Sianoudis L. H. Grimme D. Leibfritz A. Mayer 《Archives of microbiology》1989,151(5):434-438
The possibility to apply N-15 in vivo NMR spectroscopy to study algal N-metabolism has been investigated. N-15 labelled cells
of the green alga Chlorella fusca, subjected to nitrogen starvation and N-14 labelled cells supplied with K15NO3 after prolonged nitrogen starvation were monitored by N-15 in vivo NMR spectroscopy at different times after the change in
their nitrogen supply. During 20–40 min, necessary for the acquisition of 1 spectrum, the cells were under dark anaerobic
conditions, but the relative amounts of the metabolites detected did not change. Signals from 2 acid amides, from the side
chain nitrogens of arginine and lysine, from prolin as well as 4 signals from α amino groups of amino acids were detected.
Besides two signals not yet reported in the literature were found. They may be due to amino compounds, but not to amino acids.
The amount of free amino acids in the cells increases not only upon resupply of nitrogen starved cells with nitrate but also
during the first hours after nitrate depletion. The spectra obtained from N-15 labelled autospores show that N-15 in vivo
NMR spectroscopy can be applied to the investigation of N metabolism of the cells. 相似文献