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121.
Antanas A. Glema 《Journal of molecular recognition : JMR》1990,3(3):137-141
In this review the results of the interaction of the active dyes used in the USSR textile industry with microbial enzymes and blood serum proteins are discussed. The complexity of dye/protein interaction and the dependence of this interaction on different factors is demonstrated. Some practical aspects of the use of dye containing sorbents are presented and discussed. Their suitability for RNA ligase and DNA ligase, acetate kinase, alcohol dehydrogenase, lactate dehydrogenase and glucose-6-phosphate dehydrogenase purification and blood serum protein fractionation is demonstrated. 相似文献
122.
The osmotic water outflow of large multilamellar liposomes containing 1-acid glycoprotein was measured at a temperature near the lipid's phase transition temperature. The liposomes were formed from a mixture of DPPC, cholesterol and glycoprotein in molar ratios 100:20:1, by continuous sucrose density gradient centrifugation. These liposomes captured 35% of the radiolabeled glycoprotein. The temperature-dependent experiments showed that near phase transition temperature the initial rate of water outflow increased drastically in comparison with glycoprotein free liposomes incubated in buffer containing glycoprotein. We suggested that eventual a channel mechanism may be involved due to spontaneous incorporation of glycoprotein into the bilayer. 相似文献
123.
Pseudomonas fluorescens biovar I was isolated from a pulp mill effluent based on its ability to grow on synthetic media containing 1,2-diarylethane structures as the sole carbon and energy source. Analysis of samples taken from cultures of this strain in benzoin or 4,4-dimethoxybenzoin (anisoin), showed that cleavage between the two aliphatic carbons takes place prior to ring fission. Intermonomeric cleavage was also obtained with crude extracts. Substrates of this reaction were only those 1,2-diarylethane compounds that supported growth of the bacterium. The purification and partial characterization of an enzyme that catalyzes the NADH-dependent reduction of the carbonyl group of benzoin and anisoin is also reported. 相似文献
124.
Dr. Concepción Calvo Ana García de la Paz Victoria Bejar Emilia Quesada Alberto Ramos-Cormenzana 《Current microbiology》1988,17(1):49-53
Thirty-eight strains ofDeleya halophila species were examined for production of phage after mitomycin C induction. Thirty-two of them were able to inhibit growth of some other strains. Phage F9-11, isolated fromD. halophila strain F9-11, showed an isometric head and a noncontractile tail. The effects of salt concentrations variation on the stability and replication of this phage were established. Its replication was possible at a wide range of marine salt concentrations, from 2.5% to 15% (wt/vol). Stability seems to be influenced by osmolarity of medium rather than by NaCl level. The euryhaline character showed by F9-11 phage is evoked as an important factor for the survival of this phage in its environment. 相似文献
125.
Hélène Pelletier Nils-Olivier Olsson Catherine Fady Danièle Reisser Patricia Lagadec Jean-François Jeannin 《Cancer immunology, immunotherapy : CII》1988,26(3):263-268
Summary DHD/K12 TRb (PROb) and DHD/K12 TSb (REGb) are two cancer cell variants originating from the same rat colon adenocarcinoma. They differ in their tumorigenicity: when inoculated into syngeneic BDIX rats, PROb cells induce progressive tumors whereas REGb cells induce tumors which always regress. As previously described, there is an inverse relation between their tumorigenicity and their susceptibility to NCMC mediated by syngeneic spleen or peripheral blood lymphocytes: PROb cells are significantly less sensitive to NCMC than REGb cells. This suggests a role for NCMC in the regression of REGb tumors. In this work the BDIX NCMC effector cells active in vitro against REGb cells were identified as NK cells according to four criteria: (1) efficacy in a 4-h 51Cr release assay, (2) sensitivity to anti-asGM1 antibody plus complement, (3) LGL morphology, and (4) ability to bind with the same affinity REGb and YAC-1 cells. In spleen, these NK cells were heterogeneous with respect to their asGM1 surface density and their morphology. PROb cells were not lysed by these NK cells in a short-term cytotoxicity assay, but only in a 16-h assay. It was shown that PROb and REGb cells were bound with the same affinity by NK cells, thus they certainly differ in their ability to resist to NK lytic mechanisms. This difference could play a role in the different tumorigenicity of the two variants.
Abbreviations used: NK, natural killer; NC, natural cytotoxic; NCMC, natural cell-mediated cytotoxicity; asGM1, asialo GM1; LL, large lymphocytes; LGL, large grnular lymphocytes; LAL, large agranular lymphocytes; PBMNC, peripheral blood mononuclear cells; E:T, effector to target cell ratio; C:H, cold to hot cell ratio; FBS, fetal bovine serum 相似文献
126.
A marked decrease in overall learning capacity has been observed in rats injected with cyanate. Therefore it was of interest to test whether learning influenced carbamylation of brain proteins. Incorporation of [14C]cyanate into proteins of the mamillary body was selectively modified following operant conditioning of the rat, so that trained rats showed an asymmetric image with higher levels of incorporation in the right side than in the left side, as compared to control rats. These results were confirmed using fluorescein isothiocyanate. The asymmetry persisted once the learning had been well established. 相似文献
127.
María Jesús Martínez Covadonga Vázquez Francisco Guillén Fuensanta Reyes 《FEMS microbiology letters》1988,55(3):263-267
Abstract A β-glucosidase from centrifugated autolyzed cultures of Alternaria alternata has been purified 71 times by Sephadex G-200, CM-Biogel A and DEAE-Biogel A successively. The enzyme is a glycoprotein with 16% sugar and a M r of 160 000, formed by two subunits of 60 000 and 80 000. The enzyme has optimum pH of 5 units and optimum reaction temperature of 50°C, being stable in a pH range of 3–8 and 0 to 60°C. The enzyme hydrolyzes different substrates showing maximum affinity and maximum hydrolysis velocity on cellobiose. The β-glucosidase is inhibited by gluconolactone but not by 10 mM glucose. 相似文献
128.
Serum copper and zinc levels were determined in 20 healthy women and in 100 women with gynecological tumors. Malignant and
benign tumor cases were separated according to their postoperative, histopathological examinations. The stages of malignant
and benign tumors were also established histologically. Seventy benign and 30 malignant genital tumors (carcinoma of cervix
in situ, cervix, ovary endometrium, and vulva) of the patients were differentiated histopathologically.
The serum Cu/Zn ratios of patients were increased significantly from the control group (0.32±0.35) to the benign group (1.22±0.63)
and from the benign group to the malignant group (2.24±1.03). Nine of 30 malignant cases were determined as false negative
(30%) and 15 of 70 benign cases were determined as false positive (14.2%) according to the serum Cu/Zn ratios of patients.
Serum copper levels of 30 malignant and 10 benign tumor cases showed linear correlation with serum ceruloplasmin values. 相似文献
129.
The carcinogenicity of several groups of carcinogens is evoked with particular reference to Dibenzo(c,g)carbazole derivatives. The activity of these derivatives is discussed with respect to their species and organ specificity. The enzymatic equipment is decisive as to whether the compounds formed can react with DNA or are simply detoxified and eliminated. All these carcinogens are complete carcinogens, i.e. they have the property of both initiation and promotion. 相似文献
130.
Chromium is an essential trace element and is associated with some biological pathways, especially with glucose tolerance.
For these reasons, we decided to determine the concentration of chromium in two sets of Brazilian medicinal plants. The first
group consisted of plants that are considered as antidiabetic, whereas the second included plants that do not have this therapeutic
property. The concentration of chromium was determined by flameless atomic absorption. All the plants analyzed contain chromium
in the normal range for this element, but the hypoglycemic plants contain more chromium than the others (1–4 μg/g compared
to 0.5–1.5 μg/g). 相似文献