nature of the lectin-induced activation of plasma membrane mg2+atpase.the mg2+atpase activity of liver plasma membranes decreases markedly with increasing temperature above 30 degrees. this negative temperature dependency is counteracted by the binding of wheat germ agglutinin, concanavalin a, or ricinus communis agglutinin (at concentrations greater than or equal 0.5 mg/ml) to membranes prior to assay of the enzyme. with one of these lectins bound, the enzyme has a single energy of activation between 20 degrees and 45 degrees. the binding of dimeric succinyl conc ...197718464
binding of lectins to streptococcus mutans cells and type-specific polysaccharides, and effect on adherence.the lectin concanavalin a (con a) agglutinated the cells of 13 of 15 strains of the seven serotypes of streptococcus mutans in an 18-h incubation period. strains of types a, d, f, and g agglutinated within 2 h. strains of a, d, and f were also agglutinated in 2 h by the castor bean lectin rca. s. sanguis, s. salivarius, s. bovis, actinomyces viscosus, a. naeslundii, and lactobacillus plantarum were agglutinated within 2 h. the s. mutans type f polysaccharide was precipitated by con a. the a, b, ...197722491
lectin-mediated agglutination of amphibian embryonic cells.dissociated blastula cells of xenopus laevis are agglutinated with wheat germ agglutinin (wga), ricinus communis agglutinin (rca), concanavalin a (con a) and, to a lesser extent with soya bean agglutinin (sba). they are not agglutinated with fucose-binding protein. neuraminidase treatment of cells enhances their agglutinability with rca and sba, but has no effect on con a- and wga-mediated agglutinability. treatment of cells with procaine, or xylocaine, has no effect on the cells' agglutinabilit ...197722553
purification and immunochemical characterization of malate synthase from euglena gracilis.malate synthase (ec from dark-grown euglena gracilis was purified to homogeneity by the criterion of polyacrylamide-gel electrophoresis. the enzyme was released from acetate-grown cells by treatment with ultrasonic waves and purified from broken-cell suspensions by high-speed centrifugation and (nh4)2so4 fractionation, followed by gel-filtration on sepharose 6b. the final enzyme preparation was purified 190-fold compared with the crude extract. the mol.wt. of the enzyme was about 350000 ...197828738
interaction of gamma-glutamyltransferase from human tissues with insolubilized lectins.we have characterized the binding of gamma-glutamyltransferase to three insolubilized lectins. optimal binding was achieved in 2 hours at 25 degrees c for concanavalin a and at 4 derees c for ricinus communis agglutinin 120 and wheat germ agglutinin,and was also a function of the ratio of lectin protein to gamma-glutamyltransferase protein. the interaction of gamma-glutamyltransferase with these three lectins is specific, and release of bound enzyme by carbohydrates follows the same general orde ...197943783
inhibition of ige and compound 48/80-induced histamine release by lectins.lectins from ricinus communis and glycine max, as well as wheat germ agglutinin and concanavalin a, caused a dose-dependent release of histamine from mast cells present in the mixed peritoneal cells from the rat. in addition, histamine release in an ige-mediated and a compound 48/80-mediated reaction was inhibited in cells which had been pretreated with these lectins. with concanavalin a and the r. communis lectin both effect were prevented by the addition of the appropriate monosaccharides to t ...197551003
the use of flurorescein investigations with concanavalin a, lens culinaris lectin and ricinus communis lectin.investigations on methods for the utilization of fluorescein-isothiocyanate-labelled concanavalin a, lens culinaris lectin and ricinus communis lectin for immunohistological demonstration as simple sugar moieties are reported. the stainings were carried out on rabbit erythrocytes. ehrlich ascitee tumor cells and various mammalian tissues. optimum results were obtained in living cells and native cryostate tissue sections. the influence of different fixing agents and conditions of fixation on the ...197561131
rat alpha-fetoprotein heterogeneity. comparative chemical study of the two electrophoretic variants and their ricinus lectin-binding properties.two electrophoretic forms of rat alpha-fetoprotein were purified using immunosorbent chromatography and preparative electrophoresis on polyacrylamide gel slabs. some of their respective chemical properties and their affinity for the ricinus communis lectin (rcai) were compared. electrophoresis on polyacrylamide gradient gel in the presence of sodium dodecyl sulfate indicated a slight difference in molecular 74 000 for the slow alpha-fetoprotein (afpa) and 72000 for the fat alpha-fetoprotein (afp ...197770227
rat alpha-fetoprotein heterogeneity. affinity chromatography on ricinus communis sepharose column. 197770379
oestrone binding properties of nine molecular variants of rat alpha-foetoprotein.rat alpha-foetoprotein was separated into nine molecular variants by electrophoresis and affinity chromatography on ricinus communis agglutinin and concanavalin-a. the nine variants are able to bind oestrone with the same capacity of one binding site per alpha-foetoprotein molecule. the association constants seem to vary with the sialic acid composition of the iso-alpha-foetoprotein.197877165
microheterogeneity of rat, mouse and human alpha1-fetoprotein as revealed by polyacrylamide gel electrophoresis and by crossed immuno-affino-electrophoresis with different lectins.polyacrylamide gel electrophoresis and crossed immuno-affino-electrophoresis with several free lectins have been used to characterize and to compare the molecular heterogeneity of rat, mouse and human alpha1-fetoproteins. each alpha1-fetoprotein contains a variable number of electrophoretic variants depending on the gel porosity. in sds electrophoresis, two molecular size populations are present in rat alpha1-fetoprotein (mr = 74 000 and 72 000) and in mouse alpha1-fetoprotein (mr = 73 000 and 7 ...197983879
chemical, immunochemical, and structural studies of the cross-reactive antigens of streptococcus mutans aht and b13.two antigenic polysaccharides were extracted from cell walls of the cross-reactive strains streptococcus mutans aht (a) and s. mutans b13 (d). the antigens extracted from walls by the hot formamide method, were purified by affinity chromatography on columns containing the galactose-specific lectin from the castor bean and were found to be diheteroglycans consisting of galactose and glucose. antigenic specificities of both the serotype-specific and the cross-reactive sites on each polymer were st ...197988415
serum inhibitors of desialylated glycoprotein binding to hepatocyte membranes.identification of the material present in human serum which is responsible for inhibition of binding of desialylated glycoproteins to rat hepatocyte membranes was accomplished by means of affinity chromatography using sephadex to which the galactose-specific lectin, ricinus communis agglutinin (rcai) was covalently bound. rcai-sephadex was capable of extraction of virtually all of the inhibitory activity from cirrhotic serum. the rca i-bound inhibitory activity could be eluted with 0.05 m d-gala ...1978101252
expression of ricinus communis receptors on epithelial cells in oral carcinomas and oral wounds.the histological distribution of receptors for ricinus communis fraction 1 (rca1) in oral carcinomas and in oral epithelial cells during wound healing has been studied by use of fluorescein-tagged rca1. biopsies from 15 human oral carcinomas and adjacent normal mucosa showed rca1 receptors at the cell membranes in the basal and spinous layer of the normal epithelium, whereas receptors could not be demonstrated in invading islands of the tumors. in healing oral wounds from eight humans and three ...1978102424
demonstration and characterization of specific binding sites for factor viii/von willebrand factor on human platelets.the presence of specific factor viii/von willebrand factor (fviii/vwf) binding sites on human platelets has been demonstrated by using 125i-fviii/vwf and washed human platelets. binding is ristocetin-dependent and increases in proportion to the concentration of ristocetin from 0.2 to 1 mg/ml. binding of 125i-fviii/vwf to platelets can be competitively inhibited by unlabeled human or bovine fviii/vwf, but not by human thrombin, fibrinogen, alpha 2-macroglobulin, equine collagen, or a lectin of ri ...1979108291
electron microscopic demonstration of a saccharide moieties in the hypophase of the alveolar surfactant system.for electron microscopic demonstration of complex carbohydrates and simple sugars in the mouse lung, anionic dye and lectins were used. after immersion fixation of small lung tissue blocks, the alveolar surfactant system was destroyed and only membrane bound carbohydrates (cell coat) could be demonstrated by means of colloidal iron and ruthenium red. fixation of the whole lung via the visceral pleura preserved the alveolar surfactant system. only this technique afforded a distinction between cel ...1975124909
extraction and analysis of coffee bean allergens.workers in the coffee industry can develop occupational allergic disease upon exposure to dust associated with coffee manufacturing. since controversy exists as to the source or chemical nature of these allergens, the mouse model of reaginic antibody production was used to assess the potential sources of allergens in samples obtained from a local coffee manufacturing plant. mice were immunized with extracts of coffee dust and beans and the resulting reaginic antibody response determined by the p ...1978149620
qualitative and quantitative interactions of lectins with untreated and neuraminidase-treated normal, wild-type, and temperature-sensitive polyoma-transformed fibroblasts.the lectin receptors of confluently grown hamster bhk, wild type polyoma virus transformed pybhk, and temperature-sensitive polyoma transformed ts3-pybhk fibroblasts were investigated using cell agglutination, quantitative (125i)lectin binding, and ferritin-lectin labeling. pybhk and permissively grown ts3-pybhk cells agglutinated more strongly with ricinus communis i agglutinin (rca-i)compared to bhk and nonpermissively grown ts3-pybhk, although saturation binding of (125i)rca-i to these cells ...1975162828
mechanism of cell entry and toxicity of an affinity- purified lectin from ricinus communis and its differential effects on normal and virus-transformed affinity-purified plant lectin from ricinus communis (rcaii) was shown to exhibit differential toxicity toward sv40-transformed 3t3 fibroblasts grown in vitro. when macromolecular synthesis was examined in sv3t3 and 3t3 cells, rcaii suppressed cell protein synthesis in the transformed line at lower concentrations (1/50 to 1/100) compared to the 3t3 line, and these effects were blocked by the rcaii inhibitors d-galactose or lactose. rna and dna synthesis and l-leucine transport were relatively ...1975162859
effect of ricinus communis toxin on cyclic adenosine 3':5'-monophosphate metabolism in yoshida ascites sarcoma cells.prostaglandin e1 (2.5 mug/ml) enhanced the level of cyclic adenosine 3':5'-monophosphate (cyclic amp) three to four times in yoshida ascites sarcoma (ys) cells cultured in vitro. when ricinus communis toxin (rc-toxin) was added 30 min after the addition of prostaglandin e1, the enhanced level of cyclic amp in the ys cells decreased rapidly. of rc-toxin, 0.2 mug/ml was enough to produce the maximum effect. by addition of 5 mm lactose with rc-toxin, approximately 60% of the rc-toxin effect on the ...1975164448
a quantitative assay for concanavalin a- and ricinus communis agglutinin-mediated agglutinations of rat ascites hepatoma cells. relationship between concanavalin a binding and cell agglutination.a simple quantitative assay method was developed for the agglutination of rat ascites hepatoma cells mediated by concanavalin a or ricinus communis agglutinin. this method was based on the principle that the turbidity of a cell suspension is proportional to the sum of the cross-sectional area of cells and aggregatesmas predicted by the theoretical consideration, the turbidity decreased when cells were aggregated and the decrease was a function of the average number of the cells in aggregates. th ...1975164953
distribution of ferritin-conjugated lectins on sialidase-treated membranes of human erythrocytes.the labeling of sialidase-treated, human erythrocyte membranes with ferritin-conjugates of four plant lectins, concanavalin a, ricinus communis hemagglutinin, bauhinia purpurea hemagglutinin and arachis hypogoea hemagglutinin, is reported. among these ferritin-conjugated lectins, ferritin-conjugated concanavalin a and ferritin-conjugated r. communis hemagglutinin were found in clusters on the sialidase-treated membranes, whereas ferritin-conjugated b. purpurea hemagglutinin and ferritin-conjugat ...1975172150
effect of neuraminidase and papain treatment on lectin-induced agglutination of novikoff tumor cells and assay of lectin receptor activity of the glycopeptides released from the cell surface by papain.lectins, plant proteins that bind specific saccharide determinants, have been utilized to examine the effect of neuraminidase digestion on the structure and/or expression of oligosaccharide moieties present at the periphery of novikoff ascites hepatoma cells. five lectins were utilized: concanavalin a (con a), specific for alpha-d-manno- or alpha-d-glucopyranosyl residues; wheat germ agglutinin, specific for 2-acetamido-2-deoxy-d-glucopyranosyl residues; ricinus communis agglutinin i (rcai), spe ...1976174811
interaction of lens culinaris lectin, concanavalin a, ricinus communis agglutinin and wheat germ agglutinin with the cell surface of normal and transformed rat liver cells.the observation of borek et al. (1973) on nonagglutinability of transformed rat liver cells by lens culinaris lectin and our ultrastructural findings of a greater mobility of the lens culinaris lectin receptors on transformed rat liver cells as compared to normal rat liver cells (roth 1975) initiated the present agglutination experiments on liver cells with lectins. for agglutination assay the microhemadsorption technique after furmanski et al. (1973) was used with exception of several tests on ...1975183974
isolation of mammalian trnaasp and trnatyr by lectin-sepharose affinity column chromatography.trnaasp from rabbit liver, rat liver and rat ascites hepatoma was readily isolated by concanavalin a-sepharose (con a-sepharose) affinity column chromatography. trnatyr from these sources was extensively purified by ricinus communis lectin-sepharose column chromatography. these results, together with the chromatographic behaviour of four trnas (trnatyr, trnahis, trnaasn and trnaasp) on acetylated dbae-cellulose column chromatography suggested that trnaasp contains a q nucleoside species having a ...1977190593
developmental alteration of rat brain synaptic membranes. reaction of glycoproteins with plant lectins.synaptic membranes were isolated from the forebrains of rats of increasing postnatal ages. developmentally related changes in the structure and concnetration of synaptic membrane glycoproteins were indicated by: (1) a 2--3 fold increase in glycoprotein sialic acid between 5 and 60 days; (2) a similar increase in the number of membrane receptors for the lectins concanavalin a and wheat germ agglutinin; (3) transient increases between 10 and 17 days in the receptors for lentil and castor bean lect ...1979217493
cell surface components of intestinal epithelial cells and their relationship to cellular differentiation.the surfaces of the epithelial cells of the rat small intestine were studied by fluorescence microscopy using various fluorescein isothiocyanate-conjugated lectins. throughout most of the adult intestine changes were detected in the luminal surfaces as the cells differentiate and move from the crypts to the villi. these changes in cell surface material depend upon the region of intestine in which the villi are located. by the end of the second week of postnatal development the cell surface compo ...1979261527
erythropoietin: isolation by affinity chromatography with lectin-agarose derivatives.affinity chromatography using agarose-bound lectins was used to isolate erythropoietin from crude preparations of sheep plasma and human urinary erythropoietin. on the basis of previous estimates of the sugar content of the hormone, six lectins (wheat germ agglutinin, phytohemagglutinin, ricinus communis 120, soybean agglutinin, concanavalin a, and limulin) were chosen for study. only wheat germ agglutinin-agarose and phytohemagglutinin-agarose derivatives had significant affinity for erythropoi ...1977270704
coupled cell-free synthesis, segregation, and core glycosylation of a secretory protein.mrna from rat mammary glands 13-15 days post partum was translated in a wheat germ cell-free system either in the absence or in the presence of ribosome-denuded membranes prepared from isolated rough microsomes of dog pancreas. newly synthesized alpha-lactalbumin was identified by immunoprecipitation with a monospecific rabbit antiserum against rat alpha-lactalbumin and was characterized by partial amino-terminal sequence determination and by lectin affinity chromatography. in the absence of mem ...1978276877
isolation and partial characterization of the major sialoglycoprotein of human t-lymphoblastoid cells of a molt-4b cell line.a sialoglycoprotein with an approx. mol.wt. of 95000 was isolated from human lymphoblastoid cells of a molt-4b cell line, which was of human t-lymphocyte origin, by ion-exchange chromatography, affinity chromatography on a column of wheat-germ agglutinin-sepharose and preparative slab-gel electrophoresis. the localization of this glycoprotein on the cell surface was indicated by surface labelling by the periodate/nab3h4 and lactoperoxidase-catalysed iodination methods. carbohydrate analyses of t ...1978311197
guinea-pig lymphotoxin resistant l-cell sublines.guinea-pig lymphotoxin (glt)-resistant l-cell sublines were isolated, and the altered properties were characterized. two of them (no. 1 and no. 2 cells) showed the lowest capacity to absorb glt and substantially reduced ability to bind labelled ricinus communis agglutinin (rca). both the cell-surface proteins and glycoproteins of no. 2 cells were found to be quite different from those of parental l cells. the glycoprotein of molecular weight 140,000, which specifically bound to rca-sepharose, wa ...1979311338
[is there a correlation between sugar content, thrombocyte aggregating activity and molecular size of factor viii?].human and bovine factor viii, isolated from cryoprecipitates of fresh plasma by gel filtration on sepharose cl-2b, gave similar elution patterns and showed comparable distribution of oligomers on sds agarose electrophoretic gels. the carbohydrate content of individual factor viii bands, measured by reaction with dansyl hydrazine or binding of glucose/mannose specific concanavalin a, was not directly related to the size or von willebrand activity of factor viii oligomers. staining of disulfide-re ...1979314662
a statistical evaluation of the binding of ferritin-conjugated lectins to the surface of rat cells. topographical variations as a function of lectin concentration and cell type.statistical procedures were utilized to evaluate the concentration dependence of labeling by ferritin-conjugated lectins on four different rat cells: hepatocytes, normal thymocytes, friend virus-induced rat tumor cells and feline sarcoma virus-induced rat sarcoma cells. labeling by ferritin conjugates of concanavalin a, wheat germ agglutinin and ricinus communis agglutinins i and ii was quantitated by counting the number of ferritin granules on 600 angstrom membrane segments. relationships betwe ...1979316439
the lectin binding sites on the plasma membrane components of human lymphoblastoid cell lines.the plasma membrane components of five human b-cell lines and three human t-cell lines were separated by dodecyl sulfate polyacrylamide gel electrophoresis, incubated with the radioactive labeled lectins from lentil, castor bean, wheat germ, phaseolus bean, peanut, gorse and the roman snail and the molecular weights of the binding sites determined. the lentil, castor bean and wheat germ lectin bound to multiple components from molecular weights (mr) 20 000 to 200 000 within the plasma membranes, ...1979316801
the use of fluorescein isothiocyanate labelled lectins for immuno-histological demonstration of saccharides. iii. studies by use of ricinus communis lectin and wheat germ agglutinin.cryostat sections of heart, skeletal muscle, spleen, liver, cartilage, brain, nerve, tongue, esophagus and salivary gland from man, rabbit, rat and guinea pig were stained with fluorescein isothiocyanate labelled ricinus communis lectin and wheat germ agglutinin. the stained sections were examined by fluorescence microscopy. the general pattern of fluorescence is very similar to that obtained with labelled lens culinaris lectin and concanavalin a. particularly the lectins stain connective tissue ...1977338333
use of yeasts in affinity chromatography.the use of the yeast candida lipolytica as a support in affinity chromatography for the purification of lectins of ricinus communis seeds has been studied. a comparison was made with columns of erythrocyte stromas and sepharose 4b with respect to protein yields, the agglutinating activity yield, and the electrophoretic characteristics of the eluted substances. even though the yield is less than with other supports, it does appear that the yeast columns represent an effective method for the purif ...1978355556
ultrastructural localization of beta-d-galactan in the nuclei of the myxomycete physarum polycephalum.the acellular slime mold physarum polycephalum produces an extracellular sulfated and phosphorylated beta-d-galactan which was recently isolated from the nuclei of this organism. this polysaccharide has now been localized in the nuclei of p. polycephalum by electron microscopy using a specific "sandwich" technique: thin sections of p. polycephalum microplasmodia were incubated with the ricinus communis lectin specific for d-galactose residues. the bound lectin was then localized with gold granul ...1978356891
inhomogeneity of surface labelling of b-cells at prospective sites of exocytosis.using ferritin-labelled ricinus communis agglutinin to detect lectin-binding sites of the pancreatic b-cell surface, we show that limited regions of the plasma membrane are deprived of lectin-binding sites over marginated secretory granules. such deprived regions increased during glucose stimulation of b-cells in monolayer culture: 56 +/- 8 of them were found in high (300 mg/100 ml) glucose as compared to only 27 +/- 5 in low (50 mg/100 ml) glucose (p less than 0.005). in addition, non-membrane, ...1979365658
affinity of bronchial secretion glycoproteins and cells of human bronchial mucosa for ricinus communis lectins.the coupling of ricinus communis lectins to sephadex g 25 was used in order to study mucins and other glycoproteins from human bronchial secretion. the major part of human bronchial mucins and other glycoproteins such as immunoglobulins a, bronchotransferrin and alpha1-antichymotrypsin were isolated by this procedure. a parallel study of human bronchial mucosa was achieved with peroxidase labeled ricinus communis lectins; this study characterized goblet cells and mucous cells which contain mucin ...1977411525
isolation of galactoprotein a from hamster embryo fibroblasts and characterization of the carbohydrate unit.a major cell surface labeled glycoprotein of hamster embryo fibroblasts, with a subunit molecular weight of 230 000, which is deleted on viral transformation [gahmberg, c. g., & hakomori, s. (1973) proc. natl. acad. sci. u.s.a. 70, 3329--3333; hynes, r. o. (1973) proc. natl. acad. sci. u.s.a. 70, 3170--3174], was quantitatively extracted and purified on an insolubilized ricinus communis lectin--poly(acrylhydrazido)agarose column. a glycopeptide with a molecular weight of 2000 was isolated from t ...1979420811
the rapid transmembrane movement of cholesterol in small unilamellar vesicles.the exchange of cholesterol between two populations of small unilamellar vesicles has been investigated using a new system. uniformly sized egg lecithin-cholesterol vesicles containing [3h]cholesterol and the glycolipid n-palmitoyl-dl-dihydrolactocerebroside were used as donors, whereas similar vesicles containing unlabelled cholesterol and no glycolipid were used as cholesterol acceptors. the two populations of vesicles were separated with the castor bean lectin ricinus communis. it was found t ...1979420833
distribution of cell surface saccharides on pancreatic cells. ii. lectin-labeling patterns on mature guinea pig and rat pancreatic cells.the surface saccharide composition of collagenase-dispersed pancreatic cells from adult guinea pig and rat glands was examined by using eight lectins and their ferritin conjugates: concanavalin a (cona); lens culinaris (lcl); lotus tetragonolobus (ltl); ricinus communis agglutinins i and ii (rca i, rca ii); soybean agglutinin (sba); ulex europeus lectin (uel); and wheat germ agglutinin (wga). binding studies of iodinated lectins and lectin-ferritin conjugates both revealed one population of satu ...1979422654
syntheses of o-beta-d-galactopyranosyl-(1 leads to 3)-0-(2-acetamido-2-deoxy-alpha(and -beta)-d-galactopyranosyl)-n-tosyl-l-serine and their interaction with d-galactose-binding order to use, as hapten inhibitors against various galactose-binding lectins, the derivatives of o-beta-d-galactopyranosyl-(1 leads to 3)-o-(2-acetamido-2-deoxy-alpha-d-galactopyranosyl)-l-serine, which is the common core structure of sugar chains of most mucins, the synthesis of these compounds was investigated. koenigs-knorr condensation of the 4,6-o-benzylidene derivative of o-(2-acetamido-2-deoxy-alpha-d-galactopyranosyl)-n-tosyl-l-serine methyl ester with 2,3,4,6-tetra-o-acetyl-alpha-d-g ...1979427833
differences in the redistribution of concanavalin a and wheat germ agglutinin binding sites on mouse neuroblastoma cells.concanavalin a (con a), wheat germ agglutinin (wga), and ricinus communis agglutinin (rca) bound with either 125i, fluorescent dyes, or fluorescent polymeric microspheres were used to quantitate and visualize the distribution of lectin binding sites on mouse neuroblastoma cells. as viewed by fluorescent light and scanning electron microscopy, over 10(7) binding sites for con a, wga, and rca appeared to be distributed randomly over the surface of differentiated and undifferentiated cells. an ener ...1979439895
effect of intraventricularly injected ricin on protein synthesis in rat brain.ricin, a protein from the seeds of ricinus communis which inhibits protein synthesis by eukaryotic ribosomes, is highly toxic when injected intraventricularly to rats, the ld50 being 0.241 micrograms/rat at 72 hr and 0.084 micrograms/rat at 7 days. poisoned animals showed signs of central depression; they did not die before 20 hr of intoxication. incorporation of amino acids in vivo into brain total protein and into brain ribosomes was impaired, as was protein synthesis in vitro by microsomes is ...1979460522
lectin-mediated agglutination of murine lymphoma cells. cell surface deformability and reversibility of agglutination by saccharides.agglutination of s49 mouse lymphoma cells by ricinus communis i agglutinin can be reversed by the competing haptenic saccharide, lactose, soon after agglutination, but after further incubation in the absence of lectin the agglutination reaction could not be reversed by lactose and the cells remained as multicell aggregates. the irreversibility of s49 cell agglutination was time, temperature and lectin concentration dependent and its onset correlated with ultrastructurally observed deformation of ...1979486456
inhibition of protein synthesis in vitro by a lectin from momordica charantia and by other haemagglutinins.protein synthesis by a rabbit reticulocyte lysate is inhibited by the haemagglutinating lectins from momordica charantia and crotalaria juncea seeds and from the roe of rutilus rutilus, and by a commercial preparation of the mitogenic lectin from phytolacca americana. the haemagglutinins from the seeds of ricinus communis and of vicia cracca acquired inhibitory activity after their reduction with 2-mercaptoethanol.1979508306
lectin-associated proteins from the seeds of leguminosae.the seeds of pisum sativum (pea), canavalia ensiformis, vicia faba, vicia sativa, and ricinus communis were shown to contain proteins which are associated to the respective lectins (lectin binders). the lectin binders from pisum sativum and canavalia ensiformis were studied more closely. both are single proteins not resembling the variety of membrane glycoproteins found in animals and plants which bind to lectins. the pea lectin binder is a tetrameric glycoprotein composed of identical subunits ...1979511093
large animal hepatotoxic and nephrotoxic plants.the hepatotoxic and nephrotoxic plants of large domestic animals have been reviewed. the most important ones are those widely distributed as weeds over pastures, negelcted forests and grasslands, those used as ornamentals, the nitrate concentrating forage crops, and the cyanophoric plants. crotolaria spp, the ragwort (senecia jacobaea), the lantana spp. and heliotopum are common hepatoxic plants. amaranthus retroflexus, datura stramonium, solanum rostratum, and the castor oil plant (ricinus comm ...1979516370
cytotoxic, cell agglutinating, and syncytium forming effect of purified lectins from ricinus communis on cultured cells.the toxicity of lectins from castor bean (ricinus communis l.), ricin-d, ricin-e, and castor bean hemagglutinin, was investigated on five cultured cell lines. the differential effect of their constituent polypeptide chains was also investigated using these cell lines. ricin-d, ricin-e, and castor bean hemagglutinin (cbh) possessed cytoagglutinating activity and cytotoxic activity to all five cell lines. these lectins showed the strongest toxicity to l5178y cells, which are leukemic cells. the to ...1979520750
age-related cell surface changes in human diploid fibroblasts revealed by lectin-mediated red blood cell adsorption assay: a lectin survey.two types of age-related cell surface changes could be demonstrated in human diploid fibroblasts with the two methods of the lectin-mediated red blood cell (rbc) adsorption assay: the fibroblast coating method (in which rbcs are adsorbed to lectin-coated fibroblasts) and the rbc coating method (in which lectin-coated rbcs are adsorbed to fibroblasts). with the fibroblast coating method, concanavalin a and agglutinin l from phaseolus vulgaris gave a change in rbc adsorption which did not occur th ...1979522510
the lectin binding sites on the membranes of the nuclear envelope, mitochondria and the cell surface of human lymphoblastoid cells.the membranes of the cell surface, the endoplasmic reticulum, outer and inner mitochondrial leaflet and nuclear envelope were isolated from three human lymphoblastoid cell lines. membrane components were separated by dodecyl sulfate polyacrylamide gel electrophoresis and the gels incubated with the radioiodinated lectins from lentil, castor bean, scarlet runner bean, gorse seed and roman snail. after gel slicing and counting, the molecular weights of the lectin binding sites were determined. abo ...1979527941
lectin-binding proteins in central-nervous-system myelin. binding of glycoproteins in purified myelin to immobilized lectins.the capacities of immature and mature rat brain myelin, bovine myelin and human myelin to be agglutinated by soya-bean agglutinin, ricinus communis agglutinin, wheatgerm agglutinin, and lotus tetragonolobus agglutinin were examined. the first two lectins, which are specific for galactose and n-acetylgalactosamine, strongly agglutinated immature and mature rat myelin, weakly agglutinated bovine myelin, but did not affect human myelin. the other myelin and lectin combinations resulted in very weak ...1979534494
binding of lectins to membranes of mycoplasmas from aging cultures.the binding of iodinated concanavalin a (con a) and ricinus communis agglutinin (rca) to intact cells and isolated membranes of acholeplasma laidlawii, mycoplasma hominis and mycoplasma capricolum decreased with the progression of the culture from the mid- to the late-logarithmic phase of growth. the binding of the lectins to acholeplasma laidlawii membranes had no significant effect on membrane fluidity, as assessed by electron-paramagnetic resonance spectroscopy of spin-labelled fatty acids, a ...1979542135
lectin affinity chromatography of cell surface proteins of novikoff tumor cells.novikoff hepatocellular carcinoma cells were radioiodinated by a cell surface-specific method using lactoperoxidase/125i. the iodinated proteins were solubilized in 0.5% nonidet p-40 and subjected to affinity chromatography on sepharose-conjugated lectins (ricinus communis agglutinins i or ii, soybean agglutinin, concanavalin a, or wheat germ agglutinin) and analyzed by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. almost all the iodinated proteins bound to one or ...1979544927
[lectins as reagents for the differentiation of serum enzymes. lectins as reagents, i. (author's transl)].lectins from canavalia ensiformis, phaseolus vulgaris, and triticum vulgare react with arylamidase, alkaline phosphatase, gamma-glutamyltransferase, and cholinesterase of human sera by formation of enzymatically active, mostly insoluble complexes. arylamidase, alkaline phosphatase, and cholinesterase react more intensely in sera of healthy people than in sera of patients with liver and neoplastic diseases. arylesterase is bound to a distinct degree only by concanavalin a. the enzymes mentioned a ...1979547035
studies on lectins. xxxvi. properties of some lectins prepared by affinity chromatography on o-glycosyl polyacrylamide gels.a number of lectins has been purified by affinity chromatography on o-glycosyl polyacrylamide gels. the lectins isolated (and the particular sugar ligands used in the affinity carriers) are as follows: anguilla anguilla, serum (alpha-l-fucosyl-), vicia cracca, seeds; phaseolus lunatus, seeds; glycine soja, seeds; dolichos biflorus, seeds; maclura pomifera, seeds; sarothamnus scoparius, seeds; helix pomatia, ablumin glands; clitocybe nebularis, fruiting bodies (all n-acetyl-alpha-d-galactosaminyl ...1978563738
additional precipitation reactions of lectins with human serum glycoproteins.highly purified human serum glycoproteins were treated with neuraminidase and examined for their cross reaction with several lectins with anti-galactosyl specificity: beta-d-galactosyl structures are thought to be the main terminal sugar residues that become attached de novo after removal of neuraminic acid. the following lectins were tested: tridacnin from the bivalve clams tridacna maxima and tridacna gigas, the agglutinin from the sponge axinella polypoides, the lectin from the roach rutilus ...1978564939
the binding of lectins to components of plasma membranes from porcine submaxillary lymph node sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis the plasma membranes from porcine lymphocytes contain at least 30--35 glycopolypeptides and one or more glycolipids to which one or more of 12 purified lectins bind. the specificities of binding generally followed the same pattern as those of the reaction of the lectin with intact pig lymphocytes. some lectins (e.g., the isolectin pair, agaricus bisporus lectins a and b and a group consisting of the lens culinaris a and b isol ...1978568485
carbohydrate composition of variant-specific surface antigen glycoproteins from trypanosoma brucei.the carbohydrate of variant-specific surface antigen glycoproteins from bloodstream forms of 13 cloned variants of trypanosoma brucei was analyzed by gas-liquid chromatography. the glycoproteins contained from 6 to 17% carbohydrate by weight, and all contained the same 4 sugars: mannose, galactose, glucose, and glucosamine (probably as n-acetylglucosamine). the glycoprotein from variant 048, strain 427 contained (+20%) 11 mannose, 4 galactose, 4 glucose, and 5 glucosamine residues/mole of glycop ...1977599504
concanavalin a and ricinus communis receptor sites in normal human oral mucosa.fluorescein conjugates of concanavalin a (con-a) and ricinus communis fraction 120 (rca120) were shown to bind to the cell surfaces of basal and spinous cell layers in oral buccal mucosa. palatal epithelium showed distinct binding to basal and spinous cells; cell membranes in the granular layer occasionally bound con-a and always rca120. the ultrastructural localization of con-a binding sites on exfoliated buccal cells was detected by the con-a peroxidase staining method. the con-a receptors wer ...1978618974
lectin-binding sites are found in rat liver cell plasma membrane only on its extracellular the present study ultrastructural localization of binding sites for 5 lectins was studied in rat liver cell surface membrane fractions. for this purpose ferritin-coupled concanavalin a, wheat germ agglutinin, soybean agglutinin, ricinus communis agglutinin 120 and lotus tetragonolobus agglutinin i were used as probes for mannose, n-acetyl glucosamine, n-acetyl galactosamine, galactose and fucose moieties in glycoproteins and glycolipids. although recent reports suggest presence of glycogroups ...1978627608
capping of saccharides on the plasma membrane of lymphocytes as studied by fluorescein-labelled lectins.the capping of saccharides on the plasma membrane of rat splenic lymphocytes was studied by means of fluorescein-labelled lectins. treatment of unfixed splenic lymphocytes with any one of the three lectins, concanavalin a (con a), ricinus communis agglutinin (rca) and wheat germ agglutinin (wga) led to the formation of caps of each saccharide receptor on the plasma membrane. treatment of unfixed lymphocytes with con a was found to result in the formation of caps of saccharide receptors for rca, ...1978632125
extraction and partial purification of ricin from ricinus communis l.ricinus communis l., usually cultivated for production of oil, has some use in medicine, cosmetic industries and as motor oil. the defatted seed meal is very toxic, and can not be used as human or animal food. this study undertook extraction and identification of ricin, a toxalbumine, from iranian ricinus communis l. ricin, was extracted from the seeds using dilute acid solution, salted out with ammonium sulfate, and purified by sephadex g - 75 and deae - cellulose column chromatography. disc el ...1978652382
saccharide alterations in rat kidney associated with malignant transformation by injection of dimethylnitrosamine.renal tumours were induced in dietary-primed rats by injection of dimethylnitrosamine. control and tumour tissue was excised at varying periods and maintained in short-term organ culture in the presence of 3h- or 14c-fucose. the plasma membranes were then isolated, and the isotopic profiles of normal kidney and renal tumour membrane proteins were established, using polyacrylamide-gel electrophoresis in dodecyl sulphate. several fucose-containing glycoproteins of the plasma membranes were found t ...1978656300
localization of carbohydrate components in rat colon with fluoresceinated lectins.cryostat sections of rat descending colon were studied by fluorescence microscopy after exposure to conjugates of fluorescein isothicoyanate with lectins from glycine max (soybean), triticum vulgaris (wheat germ), ricinus communis (castor bean), ulex europaeus, (gorse), dolichos biflorus (horse gram) and canavalia ensiformis (concanavalin a) (jack bean). no two lectins showed identical patterns of fluorescence. fitc-conjugates of soybean and d. biflorus lectins reacted strongly with the mucus pr ...1978670681
involvement of glycoconjugates in insulin-receptor interactions. studies in liver plasma membranes of control and diabetic mice.the involvement of glycoconjugates in the insulin-receptor interactions in mouse liver is tested by digestions of membranes with various enzymes. trypsin decreased the binding of [125i]insulin to liver membranes. after digestion with beta-galactosidase no ""high affinity'' receptor sites could be detected. the effects observed with plant lectins confirm the involvement of galactoconjugates in the insulin binding process. sophora japonica and ricinus communis lectins (with galactose specificity) ...1978698217
alterations in cell surface membrane components of adapting rat small intestinal epithelium. studies with lectins after massive proximal jejunoileal resection and jejunoileal transposition.after proximal resection or transposition of intestinal segments, the small intestinal mucosa of rats was examined with fluorescein-conjugated lectins derived from ricinus communis and triticum vulgare (wheat germ). these agglutinins are thought to be specific for the nonreducing end-terminal carbohydrate residues, beta-d-galactose and beta-n-acetyl-d-glucosamine, respectively. after 70% proximal jejunoilealal resection as well as transposition of ileal segments to jejunum, ileal villus cell sur ...1978710859
homology between ricin and ricinus communis agglutinin: amino terminal sequence analysis and protein synthesis inhibition studies. 1978718174
simultaneous localization of an hepatic binding protein specific for galactose and of galactose-containing receptors on rat hepatocytes.the hepatic binding protein, specific for galactose-terminated glycoproteins (asialoglycoproteins) and the receptors for the ricinus communis lectin, specific for galactose residues (rca1), were simultaneously localized on isolated rat hepatocytes by the gold method. the marker for the binding protein was prepared from gold granules (5 nm in diam.) labeled with ceruloplasmin and desialylated. the marker specific for galactose-containing receptors consisted of granules (17 nm in diameter) labeled ...1978722052
effect of the toxic castor bean protein, ricin, on the phosphorylation pattern of [32p]-labelled ribosomes from mouse l cells. 1978743266
production of adventitious root primordia on hypocotyls of castor bean seedling, infected with agrobacterium tumefaciens.the development of sterile secondary tumours on hypocotyls of castor bean seedlings, inoculated with any of the ten isolates of agrobacterium tumefaciens tested, were observed below the site of the primary tumours. histopathological studies performed in the present work indicate that the observed secondary tumours were adventitious root primordia and not the ordinary type of secondary tumours. according to the available literature such findings are reported here for the first time. all the teste ...1978749411
binding of plant lectins to mycoplasma cells and membranes.the binding of iodinated wheat germ agglutinin, ricinus communis agglutinin, and concanavalin a to mycoplasma cells and membranes was examined. all mycoplasmas studied specifically bound concanavalin a or r. communis agglutinin and, to a lesser degree, wheat germ agglutinin. the binding of lectins to whole cells was similar to that recorded for membranes, suggesting that significant binding only occurred on the outer surface of the mycoplasma membrane. proteolysis of the membrane almost always ...1976789327
histochemical lectin affinity technique by means of fitc-labeled serum protein fractions.a two-step affinity technique is described for light microscopic demonstration of the concanavalin a, agaricus bisporus lectin and ricinus communis lectin binding sites by means of various fitc-labeled human and rabbit serum protein fractions. experiments for the visualization of the lens culinaris lectin and the pisum sativum lectin binding sites gaves negative results. the technique consist of two reaction steps which involve the incubation of tissue sections in the lectins followed by the vis ...1976791903
changes in cell surface structure by viral transformation studied by binding of lectins differing in sugar specificity.changes in cell surface structure by viral transformation were studied by examining changes in the binding of various lectins differing in carbohydrate specificities. binding of lectins was assayed directly using cells grown in coverslips. the following 125i-lectins were used: concanavalin-a (specific for glucose and mannose), wheat germ agglutinin (specific for n-acetylglucosamine), castor bean agglutinin (specific for galactose), wistaria floribunda agglutinin (specific for n-acetylgalactosami ...1975815123
effect on glutaraldehyde fixation on lectin-mediated agglutination of mouse leukaemia cells.the effect of glutaraldehyde fixation on lectin-mediated agglutination of murine leukaemia (grsl) cells was investigated using 2 assay methods which differed in the shear forces to which the agglutinated cells were subjected. first, lectin and cells were allowed to interact under conditions in which shear forces were minimized and the degree of agglutination was evaluated microscopically by the appearance and size of the cell aggregates. this assay demonstrated that concanavalin a (con a)-, whea ...1976823165
the igg subclasses of antibodies to castor bean allergen in patients with allergic asthma: detection of a high incidence of antibodies of the igg4 subclass.sera from patients with allergic asthma to castor bean dust were tested for specific antibodies in the red cell linked antigen-antiglobulin reaction (rclaar) using antiglobulin sera specific for ige and the four subclasses of igg. approximately one-third of the patients with specific igg antibodies had an antibody response that was predominantly in the igg4 subclass. two patients who were thought not to be sensitive to castor bean allergen, despite long exposure to the dust, did not have detecta ...1975830059
quantitation and isolated of ricinus communis lectin receptor from surface of crypt cells of rat intestinal epithelium. 1977852585
reciprocal interactions of ricin from ricinus communis l. seeds with eukaryote ribosomes. 1977862896
lectin-binding sites on the plasma membranes of rabbit spermatozoa. changes in surface receptors during epididymal maturation and after ejaculation.modifications in rabbit sperm plasma membranes during epididymal passage and after ejaculation were investigated by used of three lectins: concanavalin a (con a); ricinus communis i (rca(i)); and wheat germ agglutinin (wga). during sperm passage from caput to cauda epididymis, agglutination by wga drastically decreased, and agglutination by rca(i) slightly decreased, although agglutination by con a remained approximately unchanged. after ejaculation, spermatozoa were agglutinated to a similar de ...1977903374
inflammatory response of ricinus communis meal allergens. 1977914335
lectin-dependent neutrophil-mediated cytotoxicity. ii. possible mechanisms.the mechanisms whereby neutrophils become cytotoxic to chicken erythrocyte (crbc) target cells were investigated in a system of lectin-dependent neutrophil-mediated cytotoxicity (ldnmc). through the use of drugs and specific metabolic inhibitors, ldnmc was found to be dependent on energy supplied by anaerobic glycolysis and on other active metabolic functions of the neutrophil. 2-iodoacetamide, 2-deoxy-d-glucose, di-isopropyl-fluorophosphate, colchicine, cytochalasin b, and dibutyryl cyclic amp ...1976955681
immunochemical studies of infectious mononucleosis. v. isolation and characterization of a glycoprotein from goat erythrocyte membranes.a glycoprotein was isolated from goat erythrocyte membranes by extraction with hot 75% ethanol. the glycoprotein was purified by ethanol precipitation, phosphocellulose chromatography gel filtration, ethyl:ether and chloroform:methanol extraction. in aqueous phosphate-buffered saline, ph 7, the glycoprotein was in an aggregated state with a sedimentation coefficient (s(obs)) to 1.5. electrophoresis of the glycoprotein on polyacrylamide gels containing phosphate-buffered 0.1% sds gave a single ba ...1976956650
action of ricin from ricinus communis l. seeds on eukaryote ribosomal proteins. 1976964368
elucidation of lectin receptors by quantitative inhibition of lectin binding to human erythrocytes and lymphocytes.the binding to normal and sialidase-treated human erythrocytes and lymphocytes of four 125i-labeled lectins [maackia amurensis hemagglutinins (mam and mah), ricinus communis hemagglutinin (rch), and bauhinia purpurea hemagglutinin (bph)] was studied in detail. the quantitative inhibition assays against the lectin binding to the cells were also performed with various glyco-proteins and glycopeptides as inhibitors. the comparison of the inhibition constants of the inhibitors thus obtained with the ...1976974078
a comparative ultrastructural localization of concanavalin a, wheat germ and ricinus communis on glomeruli of normal rat kidney.three lectins, concanavalin a, peroxidase labeled wheat germ and peroxidase labeled ricinus communis have been utilized to determine the localization of various saccharide determinants in the glomerulus of the normal rat kidney. in order to obtain a homogeneous penetration of the lectins throughout the whole section, various technical parameters were studied. only with concanavalin a, a diffuse labeling of the endoplasmic reticulum was obtained. with the three lectins, the basement membrane, mes ...1976977938
laboratory research into the utilization of the common castor-oil plant (ricinus communis l.) in the control of rats. 1976990542
distribution and mobility of lectin receptors on synaptic membranes of identified neurons in the central nervous system.the distribution and mobility of concanavalin a (con a) and ricinus communis agglutinin (rca) receptors (binding sites) on the external surfaces of purkinje, hippocampal pyramidal, and granule cells and their attached boutons were studied using ferritin-lectin conjugates. dendritic fields of these cells were isolated by microdissection and gently homogenized. cell fragments and pre- and postsynaptic membranes were labeled with the ferritin-lectin conjugates at a variety of temperatures, and the ...1976993260
lectins as membrane components of mitochondria from ricinus communis.1. mitochondria were isolated from developing endosperm of ricinus communis and were fractionated into outer membrane and inner membrane. the relative purity of the two membrane fractions was determined by marker enzymes. the fractions were also examined by negative-stain electron microscopy. 2. membrane fractions were sequentially extracted in the following way. (a) suspension in 0.5m-potassium phosphate, ph7.1; (b)suspension in 0.1m-edta (disodium salt)/0.05m-potassium phosphate, ph7.1; (c) so ...19761008861
isolation and biochemical properties of toxic tryptic peptides of ricinotoxin from ricinus communis seeds.tryptic hydrolysis conditions of ricinotoxin were studied in order to produce not only digestion of this glycoprotein but also still toxic tryptic peptides. no hydrolysis was obtained without prior denaturation. the best conditions of denaturation were obtained with 0.2 m guanidine hydrochloride and, to a lower extent, by heat treatment at 90 degrees c during 6 minutes. the hydrolysates were fractionated on sephadex g100 column. in each case highly toxic peptide fractions were obtained which sho ...19761026428
different glycosubstances and galactans in the albumin gland and eggs of achatina saline extracts from the eggs and the albumin gland of the snail achatina fulica 3 different forms of glycosubstances have been found by using heterophile precipitins from different sources: 1. an alkali-stable galactan reacting with the anti-galactans from axinella polypoides sponge and from the clam tridacna maxima (tridacnin) and with concanavalin a. 2. another glycosubstance giving cross-reactions with a second precipitin from axinella polypoides, with the lectin from ricinus communis, wi ...19761034378
ricinus communis toxin-mediated inhibition of protein synthesis in cell-free extracts of a toxin-resistant variant mouse lymphoma cell line.ricinus communis agglutinin ii (rcaii, ricin, toxin) at low concentrations inhibits protein synthesis in cell-free extracts, but not in intact cells, of an rcaii-resistant mouse lymphoma variant cell line. the concentration dependence of the inhibition by rcaii was the same in cell-free extracts of both rcaii-resistant variant and rcaii-sensitive parental cells, while intact parental cells are 250 times more sensitive to rcaii toxicity. the onset of rcaii inhibition of cell-free protein synthesi ...19761036193
cell surface species-specific high affinity receptors for discoidin: developmental regulation in dictyostelium discoideum.vegetative (noncohesive) d. discoideum cells and cells at several stages during the development of cohesiveness were fixed with glutaraldehyde, and their agglutinability by purified carbohydrate-binding proteins (lectins) from slime molds and plants was determined. the two purified lectins from d. discoideum, called discoidin i and ii, were poor agglutinins of fixed vegetative d. discoideum cells and potent agglutinins of fixed cohesive d. discoideum cells. the increased agglutinability of d. d ...19751059141
ultrastructural localization of lectin-binding sites on the zonae pellucidae and plasma membranes of mammalian eggs.receptors for ricinus communis agglutinin i (rcai), concanavalin a (con a), and wheat germ agglutinin (wga) were localized on the zonae pellucidae and plasma membranes of hamster, mouse, and rat eggs with ferritin-lectin conjugates. intact eggs labeled with the ferritin conjugates showed dense concentrations of rcai and wga receptors in the outermost regions of their zonae pellucidae and sparse distributions of con a receptors throughout the zonae. ferritin-lectin labeling was specific, since in ...19751095597
characterization of group n streptococcus lipoteichoic acid.lipoteichoic acid was extracted from the group n organism streptococcus lactis atcc 9936 with hot aqueous phenol and purified by gel chromatography followed by affinity chromatography using ricinus communis lectin as the specific absorbent. the teichoic acid moiety of the lipoteichoic acid was calculated to contain 16 to 17 glycerol phosphate units, approximately half of which were substituted with alpha-d-galactosyl residues; the glycolipid moiety contained o-alpha-d-glucosyl-1 yields 2-o-alpha ...19751123256
immunochemical and chemical investigations of the structure of glycoprotein fragments obtained from epiglycanin, a glycoprotein at the surface of the ta3-ha cancer cell.the structures of the carbohydrate chains present in fragments of a large-molecular-weight glycoprotein, epiglycanin, cleaved from the surface of viable ta3-ha murine mammary carcinoma ascites cells and purified by gel filtration, were studied by immunochemical and chemical methods. inhibitory activities for neuraminidase-treated and untreated glycoprotein material in the hemagglutination of nn-specific human erythrocytes by eight purified lectins were determined. excellent inhibition was obtain ...19751125949
localization of the binding sites for the ricinus communis, agaricus bisporus and wheat germ lectins on human erythrocyte membranes.freeze-etch electron microscopy has been utilized to localize the binding sites for the ricinus communis, agaricus bisporus and wheat germ lectins on human erythrocyte membranes and to determine the relation of these different glycoprotein receptors to the intramembranous particles. a. bisporus lectin, which could be visualized directly on the surface of erythrocyte membranes, and ferritin conjugates of wheat germ agglutinin showed a distribution that correlates exactly with the intramembranous ...19751148231
lectin agglutinability of non-neoplastic and neoplastic human lymphoid cells in vitro.agglutination by two lectins, concanavalin a (con a) and ricinus communis agglutinin (rca), has been investigated in a human lymphoid cell system. the main conclusions of this study are: (1) no systematic correlation exists between the neoplastic state and sensitivity to con a or rca; (2) cells of neoplastic lines vary unsystematically in their surface properties as evaluated by con a agglutination, with the possible exception that presence of epstein-barr virus (ebv) is associated with a high d ...19751150344
cellular energy dependent agglutination of rat ascites tumor cells mediated by concanavalin a and ricinus communis agglutinin.effect of various metabolic inhibitors on the agglutination of rat ascites tumor cells mediated by concanavalin a and ricinus communis agglutinin was studied using a quantitative assay method for agglutination in which turbidity of cell suspension is measured. cell agglutination was inhibited by low temperature, cytochalasin b and inhibitors of energy generating systems without affecting lectin binding, and agglutination was not affected by hydroxyurea, actinomycin d or cycloheximide. the inhibi ...19751201283
inhibition of protein synthesis in mouse myeloma cells by ricinus communis toxin.the mechanism of inhibition of protein synthesis in mouse myeloma cells by ricinus communis toxin was studied. no significant disaggregation of polysomes into monosomes was detected in the toxin-treated cells. the activity of the polysomes isolated from the cells treated with the toxin in protein synthesis was remarkably lower than that of the untreated cells, while the activity of the supernatant enzyme fraction was retained. the ribosomes derived from the polysomes of the toxin-treated cells w ...19751237321
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