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Background
Lectins are carbohydrate binding proteins or glycoproteins that bind reversibly to specific carbohydrates present on the apposing cells, which are responsible for their ability to agglutinate red blood cells, lymphocytes, fibroblasts, etc. Interest in lectins has been intensified due to their carbohydrate specificity as they can be valuable reagents for the investigation of cell surface sugars, purification and characterization of glycoproteins. The present study reports the purification, characterization and evaluation of mitogenic and antimicrobial potential of a mycelial lectin from Aspergillus gorakhpurensis.Methods
Affinity chromatography on mucin-sepharose column was carried out for purification of Aspergillus gorakhpurensis lectin. The lectin was characterized for physico-chemical parameters. Mitogenic potential of the lectin was evaluated against splenocytes of Swiss albino mice by MTT assay. Antimicrobial activity of the purified lectin has also been evaluated by disc diffusion assay.Results
Single-step affinity purification resulted in 18.6-fold purification of the mycelial lectin. The molecular mass of the lectin was found to be 70 kDa and it was composed of two subunits of 34.8 kDa as determined by gel filtration chromatography, SDS-PAGE and MALDI-TOF analysis. pH optima of the lectin was found to be 6.5–9.5, while optimum temperature for lectin activity was 20–30°C. Lectin was stable within a pH range of 7.0–10.5 and showed fair thermostability. EDTA did not affect lectin activity whereas it was found susceptible to the denaturants tested. MTT assay revealed strong mitogenic potential of A. gorakhpurensis lectin at a concentration upto 150 µg/mL. Antimicrobial activity assay showed its potent antibacterial activity against Bacillus cereus, Staphylococcous aureus and Escherichia coli and marginal antifungal activity against Saccharomyces cerevisiae.Conclusion
This is the first report on the mitogenic and antimicrobial potential of Aspergillus gorakhpurensis lectin. The results will provide useful guidelines for further research in clinical applications of this lectin. 相似文献3.
D.Thambi Dorai B.K. Bachhawat S. Bishayee K. Kannan D.Rajagopal Rao 《Archives of biochemistry and biophysics》1981,209(1):325-333
A sialic acid-binding lectin, named carcinoscorpin, has been isolated from the horseshoe crab Carcinoscorpius rotunda cauda. It is a glycoprotein of molecular-weight 420,000, having two subunits of molecular weight 27,000 and 28,000, both subunits responding to glycoprotein stain. Leucine was detected as the only NH2-terminal amino acid. The sedimentation constant of the native lectin was found to be 12.7 s. On digestion with trypsin, the lectin gave 18 soluble tryptic peptides. This lectin was found to be antigenically unrelated to another sialic acid-binding lectin, limulin, isolated from the horseshoe crab Limulus polyphemus. A lectin-specific disaccharide alcohol namely O-(N-acetylneuraminyl) (2 → 6)2-acetamido-2-deoxy-d-galactitol was found to quench the typical tryptophan fluorescence of the native lectin at 332 nm. The association constant for this interaction was determined spectrofluorimetrically and found to be 1.82 × 103m?1. 相似文献
4.
The interaction of several N-acetyl-d-glucosamine analogs and of sialyl lactose with the lectin wheat germ agglutinin was studied by nuclear magnetic resonance. N-2H3-acetyl-d-gluocosamine was synthesized and found to displace the N-acetyl methyl signal toward its free chemical shift in N-acetylglucosamine and N-acetylneuraminic acid demonstrating common binding sites for the latter two compounds. The N-acetyl methyl signal of the α-methylglucoside of N-acetylglucosamine could be titrated but a 3-deoxy analog could not, the latter exhibiting very weak binding and demonstrating the importance of the 3-OH group in the binding process. Sialyl lactose (an N-acetylneuraminic acid analog) was rather tightly bound to the lectin. N-F3-acetyl-d-glucosamine was synthesized and its binding to the lectin was studied at pH 4, 4.5, 5.1 by 19F NMR. The two anomers were found to bind with nearly equal Kd′s but exhibited a pH and anomer dependent Δ (total bound chemical shift). The -CF3 analog was found to bind considerably stronger to the lectin than the -CH3 compound. The clear resolution of the α and β anomers of this molecule make it a very useful probe of the lectin binding site. 相似文献
5.
In this study, a 60.8-kDa dimeric lectin was isolated from the Phaseolus vulgaris cv. jade bean and characterized. The lectin was bound on Blue Sepharose 6 and Q Sepharose and was finally purified by size exclusion chromatography on Superdex 200. Its hemagglutinating activity toward rabbit erythrocytes was dependent on divalent cations, especially calcium ions. Various carbohydrates tested were devoid of any effect on the hemagglutinating activity. The lectin was stable at pH between 4.5 and 9.4 and temperatures between 30 and 70 °C. It did not exert antifungal activity toward Valsa mali, Setosphaeria turcica, Mycosphaerella arachidicola, Fusarium oxysporum and Bipolaris maydis. The IC50 of the antiproliferative activity of the lectin toward MCF-7 human breast cancer cells was 174 μM. It did not inhibit proliferation of WRL-68 human normal embryonic hepatocytes. The lectin was dependent on calcium ions for hemagglutinating activity and possessed a blocked N-terminus. These two characteristics make the lectin unique among Phaseolus lectins. 相似文献
6.
Isolation and Characterization of Phosphoenolpyruvate Phosphatase from Germinating Mung Beans (Vigna radiata) 总被引:15,自引:7,他引:8
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A phosphoenolpyruvate (PEP) phosphatase was purified to homogeneity from germinating mung beans (Vigna radiata). It was found to be a tetrameric protein (molecular mass 240,000 daltons) made up of apparently identical subunits (subunit molecular mass 60,000 daltons). It was free from bound nucleotides. It did not show pyruvate kinase activity. The enzyme showed high specificity for PEP. Pyrophosphate and some esters (nucleoside di- and triphosphates) were hydrolyzed slowly and phosphoric acid monoesters were not hydrolyzed. The enzyme showed maximum activity at pH 8.5. At this pH, the Km of PEP was 0.14 millimolar and the Vmax was equal to 1.05 micromoles pyruvate formed per minute per milligram enzyme protein. Dialysis of the enzyme against 10 millimolar triethanolamine buffer (pH 6.5), led to loss of the catalytic activity, which was restored on addition of Mg2+ ions (Km = 0.12 millimolar). Other divalent metal ions inhibited the Mg2+ -activated enzyme. PEP-phosphatase was inhibited by ATP and several other metabolites. 相似文献
7.
An α-glucosidase active at acid pH and presumably lysosomal in origin has been purified from human liver removed at autopsy. The enzyme has both α-1,4-glucosidase and α-1,6-glucosidase activities. The Km of maltose for the enzyme is 8.9 mm at the optimal pH of 4.0. The Km of glycogen at the optimal pH of 4.5 is 2.5% (9.62 mm outerchain end groups). Isomaltose has a Km of 33 mm when α-1,6-glucosidase activity is tested at pH 4.2. The enzyme exists in several active charge isomer forms which have pI values between 4.4 and 4.7. These forms do not differ in their specific activities. Electrophoresis in polyacrylamide gels under denaturing conditions indicates that the protein is composed of two subunits whose approximate molecular weights are 88,000 and 76,000. An estimated molecular weight of 110,000 was obtained by nondenaturing polyacrylamide gel electrophoresis. When the protein was chromatographed on Bio-Gel P-200 it was separated into two partially resolved active peaks which did not differ in their charge isomer constitution or in subunit molecular weights. One peak gave a strongly positive reaction for carbohydrate by the periodic acid-Schiff method and the other did not. Both had the same specific activity. The enzyme was antigenic in rabbits, and the antibodies so obtained could totally inhibit the hydrolytic action of the enzyme on glycogen but were markedly less effective in inhibiting activity toward isomaltose and especially toward maltose. Using these antibodies it was found that liver and skeletal muscle samples from patients with the “infantile” form or with the “adult” form of Type II glycogen storage disease, all of whom lack the lysosomal α-glucosidase, do not have altered, enzymatically inactive proteins which are immunologically cross-reactive with antibodies for the α-glucosidase of normal human liver. 相似文献
8.
The effects of the lectins concanavalin A, WGA, ricin, abrin, and the mistletoe lectins from Viscum album MLI, MLII, and MLIII on the binding of ligands of the NMDA and sigma receptors in rat hippocampus synaptic plasma membranes were investigated. Binding of [3H]MK-801, [3H]glutamate, [3H]5,7-DCKA, and [3H]glycine to the membranes was decreased by 40-60% after addition of galactose-specific lectins (mistletoe lectins MLI, MLII, ricin, abrin) at concentrations of 0.01 mg/ml, but was not affected by the glucose- and mannose-specific lectin Con A, an acetylglucosamine-specific lectin WGA, or an acetylgalactosamine-specific lectin MLIII. The binding of [3H]SKF 10047 was decreased only in the presence of MLIII and did not change after addition of the other lectins. It is suggested that lectin-sensitive ligand binding sites of sigma- and NMDA receptors are located separately, and that the carbohydrate side chains of the sigma receptor do not participate in the modulation of the NMDA-receptor. 相似文献
9.
Yasuto Watanabe Nobutake Hamada Makoto Morita Yoshio Tsujisaka 《Archives of biochemistry and biophysics》1976,174(2):575-581
An enzyme which degraded polyvinyl alcohol, a water-soluble synthetic polymer, was isolated as a single protein from a culture of a strain of Pseudomonas. The pink-colored enzyme had absorption maxima at 280, 370, and 480 nm, a molecular weight of about 30,000, and an isoelectric point at about pH 10.3. The enzyme was most active at pH values from 7 to 9 and at 40 dgC and was stable at pH values from 3.5 to 9.5 and at temperatures below 45 dgC. The viscosity of the reaction mixture decreased and the pH dropped when the enzyme acted on polyvinyl alcohol as a substrate. Furthermore, the enzyme required O2 for the reaction and produced 1 mol of H2O2, per 1 mol of O2 consumed. The molecules of polyvinyl alcohol were cleaved into small fragments with a wide distribution of molecular weights. Inorganic Hg ions markedly inactivated the enzyme, and the activity was immediately recovered by glutathione. Enzyme inhibitors tested, which included p-chloromercuribenzoic acid, KCN, o-phenanthroline, and H2O2, showed no effect on the activity. Polyvinyl alcohol oxidized by periodic acid was similarly oxidized by the enzyme. The enzyme did not oxidize most of a variety of low molecular weight hydroxy compounds examined, such as primary alcohols, secondary alcohols, tertiary alcohols, diols, triols, and polyols, except for some secondary alcohols, such as 4-heptanol. 相似文献
10.
Egg white proteins of three species of tortoises and turtle and of hen have been compared by electrophoretic and immunochemical methods. The proteins lacked similarity in electrophoresis, but tortoise and turtle egg white proteins which did not crossreact with those of the hen showed some cross-reaction among themselves. The occurrence of lysozyme as two allelic variants which were distinguishable in electrophoresis was noted only in the egg white of one of the species of tortoise, namely, Trionyx gangeticus Cuvier. Tortoise lysozyme which showed strong lytic activity toward cell walls of Micrococcus lysodeikticus did not exhibit any cross-reaction with hen lysoyzme. It was purified, crystallized, and found to be homogeneous in sodium dodecyl sulfatepolyacrylamide gel electrophoresis, immunochemical tests, and sedimentation. The physicochemical and enzymatic properties of tortoise lysozyme were found to be strikingly similar to those of hen lysozyme with minor differences which could be due to differences in their primary structure. Its average molecular weight of 15,400 was determined from sedimentation and diffusion coefficient values, Archibald experiment, and amino acid composition. The molecule appeared to undergo pH-dependent expansion at pH 2 and dimerization above pH 5.7. In enzymatic properties, tortoise lysozyme showed a specific activity of 29,000–31,000 units and gave a pH optimum at pH 7.5 and an apparent Ka value of 250 mg· liter?1. Like hen lysozyme, its activity showed strong ionic strength dependence, weak chitinase activity, susceptibility to inhibition by N-acetyl-glucosamine, and stability toward heat. 相似文献
11.
R.L. Bernstein M. Tabler D. Vestweber R. Van Driel 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,677(2):295-302
Folate deaminase released from cells of Dictyostelium discoideum is heterogenous with respect to molecular weight and stability at 60°C. The most heat-stable component isoelectrofocuses in a broad band at approx. pH 6. The Km value of this component for folate is approx. 7 · 10?7 M and Mr approx. 40 000. The major portion if not all of the deaminase binds to immobilized concanavalin A and lentil lectin. Extracellular folate deaminase has a pH-optimum of approx. pH 6.0. This is higher than that of lysosomal enzymes, which are also glycoproteins released into the extracellular medium. 相似文献
12.
Akira Takeya Osamu Hosomi Tadahisa Kogure 《Biochimica et Biophysica Acta (BBA)/General Subjects》1998,1425(1):215-223
Plant seed lectins play a defense role against plant-eating animals. Here, GalNAc-specific Vicia villosa B4 lectin was found to inhibit hydrolysis of UDP-GalNAc by animal nucleotide pyrophosphatases, which are suggested to regulate local levels of nucleotide sugars in cells. Inhibition was marked at low concentrations of UDP-GalNAc, and was reversed largely by the addition of GalNAc to the reaction mixture. In contrast, lectin inhibited enzymatic hydrolysis of other nucleotide sugars, such as UDP-Gal and UDP-GlcNAc, only to a small extent, and GalNAc did not affect such an inhibition. The binding constant of the lectin for UDP-GalNAc was as high as 2.8×105 M?1 at 4°C, whereas that for GalNAcα-1-phosphate was 1.3×105 M?1. These findings indicate that lectin inhibition of pyrophosphatase activity toward low concentrations of UDP-GalNAc arises mainly from competition between lectin and enzyme molecules for UDP-GalNAc. This type of inhibition was also observed to a lesser extent with GalNAc-specific Wistaria floribunda lectin, but not apparently with GalNAc-specific soybean or Dolichos biflorus lectin. Thus, V. villosa B4 lectin shows unique binding specificity for UDP-GalNAc and has the capacity to modulate UDP-GalNAc metabolism in animal cells. 相似文献
13.
V. Hořoejší O. Chaloupecká j. Kocourek 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,539(3):287-293
From 1 kg of dried Ononis hircina Jacq. roots 36 mg of a lectin were isolated by affinity chromatography on O-β-lactosyl polyacrylamide gel. The lectin is homogeneous as judged by ultracentrifugal analysis (s20,w = 6.2 S), polyacrylamide disc electrophoresis at pH 8.9 or 4.5, gel filtration on thin layers of Sephadex G-200 (Mr = 110 000) and dodecyl sulfate electrophoresis (Mr of sub-units 31 000, both in presence and absence of mercaptoethanol) and disc dodecyl sulfate electrophoresis (pH 9.5). The lectin contains much aspartic and glutamic acids, serine and threonine and also 7.2% of neutral sugar. It is relatively specific for human type O erythrocytes that are agglutinated at a minimal lectin concentration 0.3 μg/ml. The erythroagglutinating activity is not stimulated by Ca2+, Zn2+, Mg2+, Mn2+, Co2+, or Ni2+ salts; it is inhibited most effectively by N-acetyl-D-galactosamineandanumberofD-galactosederivatives. Dissociation constants of several lectin · sugar complexes were estimated by affinity electrophoresis. The lectin is not mitogenic in rabbit lymph nodes lymphocytes. 相似文献
14.
《Biochimica et Biophysica Acta (BBA)/General Subjects》1994,1201(1):61-68
A lectin specific to mannose has been purified from Vicia villosa seed by (NH4)2SO4 fractionation, GalNAc-Sepharose and Man-Sepharose affinity chromatography. It was defined as VVLM, which showed a single band on an acidic-PAGE stained with Coosmassie brilliant blue. The molecular weight of VVLM was 50 kDa as determined by gel filtration on Biogel P-100 column. The VVLM molecule consists of 2 distinct subunits with apparent molecular weight of 30 kDa and 22kDa determined by SDS-PAGE. VVLM has at least four isolectins with similar haemagglutinating activity. Its extinction coefficient is calculated as A1cm1 = 16.4 at 280 nm. Sugars could not be detected phenol-sulfuric acid method. The circular dichroism analysis at far UV indicated that VVLM was a β-sheet-rich protein, and gave no α-helix, 69% β-sheet, 14% β-turn by Provencher and Glockner method. The lectin was inhibited by α-methyl-d-mannose at 12.5 mM and glucose or GlcNAc at 50 mM. The carbohydrate binding specificity of VVLM was investigated by using affinity chromatography on a VVLM-Sepharose column. Among various Asn-linked oligosaccharides, core structure Manα1→3(Manα1→6)Manβ1→4GlcNAcβ1→4GlcNAcOT were found to have high affinity for VVLM-Sepharose. The antisera of VVLM did not produce precipitin line with VVLG in agar double diffusion plate indicating so serological relationship between VVLM and VVLG. However VVLM showed similar immunodeterminants of some other lectins of mannose specificity such as Con A, PSL, LCA and VFL. 相似文献
15.
Sjur Olsnes Kirsten Sandvig Kristin Eiklid Alexander Pihl 《Journal of cellular biochemistry》1978,9(1):15-25
The toxic lectin modeccin, which inhibits protein synthesis in eukaryotic cells, is cleaved upon treatment with 2-mercaptoethanol into two peptide chains which move in polyacrylamide gels at rates corresponding to molecular weights 28,000 and 38,000. After reduction, the toxin loses its effect on cells, while its ability to inhibit cell-free protein synthesis increases. Like abrin and ricin it inhibits protein synthesis by inactivating the 60S ribosomal subunits. Modeccin binds to surface receptors containing terminal galactose residues. Competition experiments with various glycoproteins indicate that the modeccin receptors are different from the abrin receptors. In addition, they were present on HeLa cells in much smaller numbers. Moreover, mutant lines resistant to abrin and ricin were not resistant to modeccin and vice-versa. The toxin resistance of various mutant cell lines could not be accounted for by a reduced number of binding sites on cells. The data are consistent with the view that the cells possesss different populations of binding sites with differences in ability to facilitate the uptake of the toxins and that in the resistant lines the most active receptors have been reduced or eliminated. 相似文献
16.
Abrin, an A/B toxin obtained from the Abrus precatorius plant is extremely toxic and a potential bio-warfare agent. Till date there is no antidote or vaccine available against this toxin. The only known neutralizing monoclonal antibody against abrin, namely D6F10, has been shown to rescue the toxicity of abrin in cells as well as in mice. The present study focuses on mapping the epitopic region to understand the mechanism of neutralization of abrin by the antibody D6F10. Truncation and mutational analysis of abrin A chain revealed that the amino acids 74–123 of abrin A chain contain the core epitope and the residues Thr112, Gly114 and Arg118 are crucial for binding of the antibody. In silico analysis of the position of the mapped epitope indicated that it is present close to the active site cleft of abrin A chain. Thus, binding of the antibody near the active site blocks the enzymatic activity of abrin A chain, thereby rescuing inhibition of protein synthesis by the toxin in vitro. At 1∶10 molar concentration of abrin:antibody, the antibody D6F10 rescued cells from abrin-mediated inhibition of protein synthesis but did not prevent cell attachment of abrin. Further, internalization of the antibody bound to abrin was observed in cells by confocal microscopy. This is a novel finding which suggests that the antibody might function intracellularly and possibly explains the rescue of abrin’s toxicity by the antibody in whole cells and animals. To our knowledge, this study is the first report on a neutralizing epitope for abrin and provides mechanistic insights into the poorly understood mode of action of anti-A chain antibodies against several toxins including ricin. 相似文献
17.
Junji Tsuzuki Henry C. Wu 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1982,720(4):390-399
The nature of binding of abrin to Chinese hamster ovary cells was examined in relation to the ensuing intoxication of the treated cells. Approx. 20% of [125I]abrin bound to CHO cells at 37°C was found to be resistant to the addition or presence of 0.1 M lactose. The extent of lactose-resistant binding depended inversely upon the temperature of incubation. Among various proteins, lectins and sugars, only non-labeled abrin could strongly inhibit the lactose-resistant binding of [125I]abrin. Lactose-resistant binding could lead to an inhibition of cellular protein synthesis and to a loss of cell viability. Abrin molecules bound at the lactose-sensitive and lactose-resistant binding sites apparently have an equal probability of being internalized by CHO cells. Binding of approx. 3·103 abrin molecules per CHO cell was required to elicit 50% loss of cell viability regardless of whether the binding occurs in the presence or absence of lactose. The result of a cross-linking experiment suggested that a membrane protein with an Mr of about 45 000 may be responsible for the lactose-resistant binding of abrin. 相似文献
18.
《Neurochemistry international》1986,9(3):409-421
Choline-O-acetyltransferase (EC 2.3.1.6; ChAT) was prepared from synaptosomal fractions (P2) of mouse and rat brain in the presence of proteolytic inhibitors by the method of Gray and Whittaker (1962) as modified by (Salehmoghaddam and Collier, 1976). The P2 fraction was hypo-osmotically shocked with glass distilled water and centrifuged to separate the cytoplasmic (S3) and vesicle-bound (P3) fractions. Fraction S3 was saved for ChAT assay and compared with the ChAT fraction eluted from the P3 by salt at a pH 7.4 or by detergent (Benishin and Carroll, 1983). These three fractions of ChAT were then compared by molecular weights, isoelectric points, immunoblotting with monoclonal or polyclonal antibodies and hydrophobicity. The results show that the S3 fraction of ChAT has a molecular weight of 66 Kd, whereas the ionically-bound fraction of ChAT has a molecular weight of 73–78 Kd. SDS-PAGE of these two ChAT fractions followed by immunoblotting revealed the presence of two immunoreactive bands at 28–29 Kd and 50–51 Kd for the ionically bound ChAT fraction. Conversely, none of these antibodies immunostained any protein bands for the S3 ChAT fraction even though one monoclonal antibody had been prepared against this ChAT fraction and the S3 ChAT fraction had a similar specific activity prior to SDS-PAGE as did the salt solubilized ChAT fraction. However, anti-ChAT monoclonal antibody MB16 binds the native S3 ChAT fraction in the co-precipitation assay.The S3 fraction of ChAT had only one isoelectric point at pH 7.8, whereas the ionically bound and detergent soluble ChAT fractions had two isoelectric points at pH 8.1–8.15 and 7.45–7.5. The S3 ChAT fraction also differed in hydrophobicity from the other two ChAT fractions. These differences between the S3 and salt soluble ChAT fractions were not obviated by addition of Triton X-100 and thus could not be attributed to the association of lipids with either of the fractions. We conclude that the water soluble fraction of ChAT in central nerve terminals differs in its physical properties and its subcellular location from that which ionically binds to membranes. 相似文献
19.
I-Chian Li Diane A. Blake Irwin J. Goldstein Ernest H. Y. Chu 《Experimental cell research》1980,129(2)
Stable and heritable variants of Chinese hamster ovary (CHO) cells which are resistant to different levels (0.1, 1.0 and 10 μg/ml) of the toxin abrin have been isolated and characterized. The frequency of resistant colonies to abrin was increased with the concentration of a chemical mutagen. There was no effect of cell density or cross-feeding on the recovery of variants. In experiments using fluorescein-labeled abrin and ricin which bind to terminal (non-sialylated) galactose residues of cell-surface oligosaccharides, parental cells exhibited strong binding toward both toxins, whereas no fluorescence was observed in the resistant clones. A fluorescein-conjugated lectin, BS II, which is specific for terminal N-acetyl-
-glucosaminyl residues, did not interact with the parental cells, but did with the resistant clones. This suggests that on the surface of resistant cells the number of terminal galactosyl residues of oligosaccharide chains in glycoproteins was reduced, exposing the penultimate N-acetyl-
-glucosaminyl residues. The number of available endogenous acceptor sites for galactosyl transferase in the abrin-resistant clones was directly proportional to the degree of resistance. In the presence of great excess of exogenous acceptor, the rates of galactosyl transfer were similar in all the abrin-resistant cell types tested, with levels ranging from 1.4 to 1.7 times parental cell values. Studies with tetraploid cell hybrids reveal that resistance was a recessive trait. Fluctuation analysis showed that abrin resistance occurred in CHO cell populations at a rate of 4−7 × 10−8/cell/generation. The system may serve as a new marker for quantitative mutagenesis studies. 相似文献
20.
Fusao Sakakibara Hiroaki Kawauchi Giichi Takayanagi 《Biochimica et Biophysica Acta (BBA)/General Subjects》1985,841(1):103-111
A lectin that agglutinates human blood group B erythrocytes but not blood group A and O erythrocytes was isolated from eggs of Ayu sweet fish (Plecoglossus altivelis). The lectin also agglutinates Ehrlich ascites carcinoma cells but not rat ascites hepatoma AH109 or rat sarcoma 150 cells tested. The lectin agglutination was most effectively inhibited by monosaccharides with the first type of configuration, i.e., L-rhamnose, L-mannose and L-lyxose at a concentration of 0.03 mM. The lectin agglutination was moderately inhibited by monosaccharides with the second type of configuration, i.e., D-galactose, D-fucose and D-galacturonic acid at a concentration of 0.4 mM. However, the agglutination was not inhibited by various other monosaccharides and oligosaccharides that have other types of configuration. The basis for an apparent B-specific hemagglutination may be due to the steric similarity of the C2 and C4 of the galactosyl series, the B-specific determinant, and the L-rhamnosyl series, which are the best inhibitors of the lectin activity. The lectin was affinity purified on an L-rhamnosyl-Sepharose column and was characterized as a homogeneous low molecular weight protein (Mr 14 000) with an abundance of hydrophobic amino acids and dicarboxylic amino acid. 相似文献