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1.
  • 1.1. Hemolymph lectins (agglutinins) of the cotton caterpillar Spodoptera littoralis were analyzed by agglutination, cross-absorption and carbohydrate-hemagglutination inhibition using several vertebrate erythrocytes.
  • 2.2. Lectins were found to interact, with all tested erythrocytes, by binding to carbohydrate moieties but showing no definite specificity.
  • 3.3. Disulphide bonds were probably absent as 2-ME treatment was ineffective.
  • 4.4. By cross-absorption studies, we have proposed that the hemolymph contains multiple lectins.
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2.
  • 1.1. Albumin purified from rhesus monkey (MSA) shows immunological cross-reactivity with human serum albumin (HSA) by RIA.
  • 2.2. The amino-terminal sequence of MSA shows a high degree of homology to HSA.
  • 3.3. Thirty minutes after injection of radioactive leucine directly into the portal vein, albumin was purified chemically from the liver, kidneys and serum.
  • 4.4. At this time, 15% of the label was incorporated into liver homogenate protein.
  • 5.5. A highly labelled immunoreactive albumin form was purified from liver to constant specific radioactivity and separated from tissue and serum albumin.
  • 6.6. The specific radioactivity of this proalbumin was 36-times higher than the specific radioactivity of albumin in liver tissue.
  • 7.7. These similarities to HSA suggest that this non human primate species can serve as a useful model of human albumin synthesis in vivo.
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3.
  • 1.1. Carp red cells were treated with drugs that affect the cell membranes. The water content of the cells and the accumulation of cAMP in the cells were measured in normoxia and in hypoxia using non-stimulated and adrenergically stimulated cells.
  • 2.2. WGA, DIDS + CCCP and A23187 increased the water content of nonstimulated normoxic cells.
  • 3.3. In hypoxia ouabain and DIDS + CCCP increased the water content but cytochalasin B, NPM, DIDS, CCCP and A23187 + CA2+ abolished the hypoxia-induced swelling.
  • 4.4. Any membrane perturbation induced some cAMP formation, Sophora and Anquilla lectins being most potent.
  • 5.5. Also in adrenergically stimulated cells, membrane perturbation generally increased cAMP formation.
  • 6.6. However, cAMP accumulation diminished in cells treated with cytochalasin B, CCCP and DIDS + CCCP.
  • 7.7. The adrenergic swelling of carp red cells was reduced in normoxia by DIDS. NPM and CCCP increased the adrenergic swelling in normoxia to hypoxic level.
  • 8.8. In hypoxia WGA and Anquilla lectin decreased the swelling.
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4.
  • 1.1. The locust vitellogenin (VTG) receptor which is embedded in oocyte plasma membranes is a glycoprotein.
  • 2.2. With various lectins oligosaccharide units have been identified, among them neuraminic acid linked to Gal or GalNAc, mannose chains, Gal linked to GalNAc or GlcNAc and fucose linked to GlcNAc.
  • 3.3. With specific enzymes it could be shown that mannose and most other oligosaccharides are O-linked while others like fucose are N-linked.
  • 4.4. Enzymatic removal of all O-linked carbohydrates resulted in a drop of the molecular mass of the receptor protein from 200,000 to 110,000.
  • 5.5. A total of N- and O-linked oligosaccharides of 54% was calculated.
  • 6.6. The isoelectric point of the receptor was found to be at pH 3.4 increasing slightly after removal of neuraminic acid.
  • 7.7. Removal of neuraminic acids destroyed the binding ability for VTG.
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5.
  • 1.1. Blood proteins were studied by polyacrylamide disc gel electrophoresis in three species of prairie dogs, Cynomys gunnisoni, C. leucurus, and C. ludovicianus.
  • 2.2. The sera were separated into 13–15 fractions and the three species could be distinguished by both qualitative and quantitative differences in their serum patterns.
  • 3.3. Qualitatively, variations in the occurrence and number of slow albumin fractions are diagnostic at the species leel.
  • 4.4. Quantitative differences were most apparent in variation in the mobility of the major albumin fraction and the transferrin fraction.
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6.
  • 1.1. Babesia hylomysci has an aminopeptidase and an acid endoprotease
  • 2.2. The amino-peptidase has properties very similar to the aminopeptidase in Plasmodium yoelii nigeriensis and P. chabaudi.
  • 3.3. The acid endoprotease is specific towards haemoglobin and practically has no action on bovine serum albumin.
  • 4.4. In mouse normal red blood cells we find an acid protease having physico-chemical properties similar to the enzyme present in B. hylomysci extracts.
  • 5.5. The similarity of electrophoretic velocity between acid protease in B. hylomysci and non-infected red blood cells leads us to think that the acid protease of parasitic extracts comes from the host-cell.
  • 6.6. The proteolytic system of Babesia and Plasmodium are similar.
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7.
  • 1.1. In a continuing investigation of phycocyanin-membrane surface interaction, fluorescence quenching experiments were performed with a mixture of two populations of fluorescence probe-encapsulated phospholipid bilayer vesicles in the presence and absence of phycocyanin.
  • 2.2. These membrane vesicles were prepared with 1,2-dimyristoyl phosphatidylcholine (DMPC), cholesterol and a probe molecule.
  • 3.3. A fluorophore was encapsulated in one population of membrane vesicles, while a quencher was encapsulated in another population of membrane vesicles.
  • 4.4. The result was compared with those of experiments in the presence of other biomolecules, including albumin, cytochrome c, hemoglobin, myoglobin or RNA.
  • 5.5. Interestingly, a one-third reduction of the fluorescence intensity was observed in the mixture of these two populations of membrane vesicles in phycocyanin's presence.
  • 6.6. In contrast, the other biomolecules caused no significant reduction in the fluorescence intensity.
  • 7.7. These findings were evidence of a phycocyanin-induced membrane perturbation.
  • 8.8. This was further demonstrated by a phycocyanin-induced change in the thermotropic behavior of DMPC vesicles, as measured by differential scanning microcalorimetry.
  • 9.9. Such a unique property of phycocyanin is believed to be associated with its known membrane surface-interacting character.
  • 10.10. A possible phycocyanin-modulated membrane-membrane interaction was discussed.
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8.
  • 1.1. The myelin protein profiles in the CNS and PNS of three species of amphibians were analyzed by biochemical and immunohistochemical methods.
  • 2.2. The CNS myelin of the African clawed frog (Xenopus) and the Mexican salamander (axolotl) contained, in addition to proteolipid protein, a unique protein zero (P0)-like protein, whereas the adult bullfrog did not.
  • 3.3. A strong expression of the P0-like protein in the bullfrog CNS myelin was found transiently at ontogenetically early phases including at the time of metamorphosis.
  • 4.4. The CNS P0-like protein and the PNS P0 protein showed a difference in reactivity with lectins and anti-L2/HNK-1 antibodies, suggesting that the two proteins differ in some aspects of their carbohydrate structures.
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9.
  • 1.1. Fifteen values were determined in blood samples from six buzzards (Buteo buteo) and six eagle owls (Bubo bubo) over the 24 hr of the day.
  • 2.2. Glucose, urea, uric acid, triglyceride and calcium values showed diurnal rhythms in both species. Their respective patterns of diurnal variation were compared.
  • 3.3. Phosphorus, cholesterol and cholinesterase levels underwent circadian rhythms only in the buzzards. Albumin/globulin and amylase exhibited diurnal variations exclusively in the eagle owls.
  • 4.4. Glutamatic oxaloacetic transaminase, albumin, globulin, total protein and creatinine concentrations did not show diurnal rhythms in either of the species.
  • 5.5. Blood values of the different parameters were studied on the basis of the ranges described in birds.
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10.
  • 1.1. This study was directed towards the characterization of the origin of the microheterogeneity displayed by mammalian tyrosinase, the enzyme responsible for pigmentation in mammals.
  • 2.2. Tyrosinase was purified from the Harding Passey murine melanoma, fractionated into a continuous series of subisozymic forms, and analyzed using various chemical and immunological probes.
  • 3.3. Treatment with neuraminidase revealed that all the forms had similar amounts of sialic acid, and reactivity with various carbohydrate specific lectins showed that the isozymes also contained subterminal galactose, N-acetylglucosamine, and mannose, but lacked α-fucose.
  • 4.4. Amino acid composition data indicated that the polypeptides of all the forms had identical residue contents.
  • 5.5. The sum of the evidence further supports the theory that the isozymic forms demonstrable for mammalian tyrosinase represent intermediate processing stages of the enzyme from the nascent protein chain to the fully glycosylated, high molecular weight form of tyrosinase that is localized within melanin granules.
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11.
  • 1.1. Protein-carbohydrate interactions are involved in a large number of biologically important recognition processes.
  • 2.2. Among the participating classes of proteins lectins are defined as carbohydrate-binding proteins other than an antibody or an enzyme.
  • 3.3. In addition to the essential carbohydrate-binding domain other functionally and/or structurally important sites, defined by sequence comparison or by experimental demonstration of protein-protein interactions, can be present within the lectin molecule and may be relevant for its physiological significance.
  • 4.4. Sequence motifs of lectins for protein-protein interactions include amino acid structures designed for cell adhesion, growth regulatory biosignalling, intracellular routing and enzymatic activity.
  • 5.5. Elucidation of the complete functional role(s) of a lectin requires accurate delineation of its carbohydrate and, if present, of its protein ligands.
  • 6.6. Presence of more than one carbohydrate-binding domain in a single lectin, potential ligand properties of the glycopart of a lectin, regulatory interplay between different sites and possible interaction of complementarily shaped peptide sequences to the sugar-recognizing site should all be assessed in the quest to comprehensively explain the physiological role(s) of a lectin.
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12.
  • 1.1. Cat plasma prothrombin and partial thromboplastin times are faster than human. Thromboplastin generation tests are very similar.
  • 2.2. Factors VIII and V assay 24 and 13 times the human standard. Cat factors VII, X. IX, XI and XII assayed at 2.5 to 4 times human. Factors I, II and XIII fell within the human range and Fletcher was extremely low.
  • 3.3. One cat lacked factor XII and showed a prolonged APTT and clotting time.
  • 4.4. Cat profibrinolysin was activated by streptokinase but not by urokinase.
  • 5.5. Cat platelets aggregated with the usual human aggregation agents with the exception of thrombin and ristocetin.
  • 6.6. Cat erythrocytes were smaller and more numerous than human.
  • 7.7. Leukocyte counts were quite variable.
  • 8.8. Serum protein electrophoretic patterns differed from human in the greater migration of albumin and the presence of numerous unidentified bands.
  • 9.9. Biochemical tests showed high sodium and chloride values.
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13.
  • 1.1. Milk proteins from nineteen species of artiodactyls and from five other species have been examined immunoelectrophoretically versus rabbit antisera for milk proteins from Bos taurus.
  • 2.2. Milks of ruminants gave positive reactions to anti-cow β-lactoglobulin and anti-cow α-lactalbumin sera. Milks from non-ruminant artiodactyls and from perissodactyls, rodents, lagomorphs and primates did not react with these antisera.
  • 3.3. Milk proteins from both ruminant and non-ruminant species reacted with anti-cow serum albumin and anti-cow casein sera.
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14.
This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:
  • 1.1. Sexual selection has probably not been the most important selection pressure on
  • 2.female human body shape.
  • 3.2. Male humans in different cultures find different aspects of the female body attractive
  • 4.and therefore are unlikely to have exerted consistent directional sexual selection on
  • 5.the female body.
  • 6.3. Breast size is not correlated with lactation success.
  • 7.4. Visible hip width is not correlated with parturition success.
  • 8.5. Women would lower their fitness if they tried to deceive men about their internal
  • 9.pelvic dimensions.
  • 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
  • 11.breast, hips, and buttocks.
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15.
  • 1.1. We report for the first time on the production and characterization of antibodies against a naturally occurring tetrahydroisoquinoline, namely salsolidine (6,7-dimethoxy-1-methyl-1,2,3,4-tetrahydroisoquinoline).
  • 2.2. Immunogen synthesis was carried out by coupling the hapten salsolidine to bovine serum albumin (BSA) as carrier protein on the basis of reductive amination.
  • 3.3. By immunization of rabbits with salsolidine-BSA conjugate antisalsolidine antibodies were produced.
  • 4.4. At a final dilution of 1:1700 the highest-litre antiserum bound 35% of 0.21 pmol [3H] salsolidine. This antiserum was used to develop a radioimmunoassay for salsolidine.
  • 5.5. Cross-reactivity studies revealed a high specificity of the antiserum to the hapten.
  • 6.6. The antibodies had a high affinity to salsolidine (Ka = 1.5 × 109 M−1).
  • 7.7. Standard curves covered a measuring range of 0.5–70 pmol/tube and the detection limit was found to be 0.27 pmol/tube.
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16.
  • 1.1. A choriolytic enzyme was isolated from the hatching medium of the pike, Esox lucius.
  • 2.2. The enzyme is defined as hatching enzyme.
  • 3.3. The molecular weight of the enzyme is 24,000.
  • 4.4. The enzyme is a glycoprotein containing 2% carbohydrate.
  • 5.5. Its isoelectric point is 6.5.
  • 6.6. The pH optimum is around pH 8.
  • 7.7. The enzyme molecule contains two disulfide bonds but no free cysteine.
  • 8.8. Inhibitor studies and metal analysis show that the enzyme is a zinc-metalloprotease.
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17.
  • 1.The proteinase fromArmillaria mellea showed no activity towards the low molecular weight substratesN-acetylglycyl-l-lysinemethyl ester,N-α-toluenesulphonyl-l-lysinemethyl ester andN-α-benzoyloxycarbonyl-l-lysinemethyl ester or towards the tetrapeptide tuftsin.
  • 2.The enzyme retained the ability to degrade bovine serum albumin after treatment with sodium dodecyl sulphate (SDS) at 50°C.
  • 3.Rapid fragmentation of an insoluble protein byA. mellea proteinase occurred when SDS was added to the incubation mixture but virtually no fragmentation occurred in the absence of SDS.
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18.
  • 1.1. Some aspects of the gas exchange system of a diving lizard, Physignathus lesuewii were studied.
  • 2.2. Breathing patterns were analysed.
  • 3.3. Breathing rate increases logarithmically with temperature and Q10 = 1.8. LogBR = −0.237 + 0.0256 T.
  • 4.4. Gas tensions in lung air and arterial and venous blood were measured. Arterial pH declines with increasing temperature.
  • 5.5. Temperature has a marked effect on oxygen affinity of the blood (ΔH = −10.1 kcal mol). A Bohr effect was also noted.
  • 6.6. CO2 equilibrium curves were drawn.
  • 7.7. The results are considered with a view to anticipating the efficiency of the gas exchange system of this species under conditions of variable temperature and during diving.
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19.
  • 1.1. Palmitoyl-CoA was found to inhibit bovine liver dihydrofolate reductase.
  • 2.2. 50% inhibition of the enzyme was obtained with 1.5 μM palmitoyl-CoA.
  • 3.3. The inhibition was reversed by addition of bovine serum albumin, β-cyclodextrin or spermine.
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20.
  • 1.1. Copper ion induced lysis of rat erythrocytes was markedly stimulated by low concentrations of ascorbate and dehydroascorbate.
  • 2.2. Ascorbate oxidase, superoxide dismutase, catalase or scavengers of hydroxyl radicals protected erythrocytes against copper-ascorbate stimulated lysis.
  • 3.3. It is proposed that superoxide radicals and hydrogen peroxide cooperate in producing hydroxyl radicals, which are directly involved in hemolysis.
  • 4.4. The serum proteins, ceruloplasmin. albumin and apotransferrin, also reduced the hemolytic action of copper-ascorbate, the order of effectiveness being; ceruloplasmin > albumin > apotransferrin.
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