• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.293-299
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• 1983

Experiments were carried out to elucidate the specific interactions between host plant, Phaseolus vulgaris, and symbiotic bacteria, Rhizobium Phaseoli. Purified P. vulgaris lectins and six species of cultured Rhizobium were subjected to agglutination test. Lectins from bean and R. phaseoli showed relatively high agglutination activity indicating that host plant lectins recognize carbohydrate moieties on the compatible Rhizobium cell surface. The specific carbohydrate receptors for binding of the lectins on the cell surface of R. phaseoli were found as mannose and galactose. The minimum concentration of sugars for the inhibition was 6.25mM. The lectin content of cultured plant roots was measured after germination and was maximum in 5-day seedlings. The nodulation was competitively inhibited by lectins for the plants cultured with Rhizobium cells. By immunochemical studies, there was some relationship in antigenic determinants between R. phaseoli and R. japonicum but no relationships were observed with other Rhizobium species. The results suggest that the infection by rhizobia to the roots of leguminous plants may be caused by the specific interaction of lectins with rhizobia.

• BMB Reports
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• v.38 no.3
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• pp.370-372
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• 2005

A cross-linked leucaena (Leucaena leucocephala) seed gum (CLLSG) matrix was prepared for the isolation of galactose-specific lectins by affinity chromatography. The matrix was evaluated for affinity with a known galactose-specific lectin from the seeds of snake gourd (Trichosanthes anguina). The matrix preparation was simple and inexpensive when compared to commercial galactose-specific matrices (i.e. about 1.5 US$/100 ml of matrix). The current method is also useful for the demonstration of the affinity chromatography technique in laboratories. Since leucaena seeds are abundant and inexpensive, and the matrix preparation is easy, CLLSG appears to be a promising tool for the separation of galactose-specific lectins.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.3
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• pp.179-186
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• 2002

Objective: Lectins are cell-agglutinating and sugar specific proteins or glycoproteins of non-immune origin that precipitate glycoconjugates having saccharides of appropriate complementarity. Because of these properties, plant lectins have been used to help characterize the carbohydrate moieties of glycoproteins in the zona pellucida (ZP) of several mammalian species including pigs. Treatment of oocytes with various lectins blocks sperm binding to the ZP in various mammalian species. This study was undertaken to examine the distribution of sugar residues in the ZP of pig oocytes matured in vitro and the ability of spermatozoa to bind to ZP and in vitro penetration in oocytes treated with fluorescein isothiocyanate (FITC)-labelled lectins. Materials and Methods: The lectins of Banderiaea simplicifolia (BS-II, bind to $\beta$-D-N-acetylglucosamine), Canavalin ensiformis (Con A, bind to $\alpha$-D-Mannose), Lens culinaris (LCA, bind to a-D-Mannose), Ricinus communis (RCA-I, bind to $\beta$-D-Galactose) and Ulex europaeus (UEA-I, bind to $\alpha$-L-Fucose) were examined for spermatozoa penetration, binding capacity to ZP and distribution of lectins. Results: The penetration rates were significantry (p<0.05) higher in control oocytes (63%) than those treated with all lectins, but penetration rates ($40{\sim}49%$) were simililar in group treated with lectins. The incidence of monospermy was similar in oocytes untreated and UEA-I, but it was higher in oocytes treated with BS-II, Con A, RCA-I and LCA. The porcine oocytes cultured for 48 h in TC-199 medium were freed from cumulus cells and treated for 30 min with fluorescein isothiocyanate-labelled lectins. When examined under fluorescein illumination, higher (p<0.001) proportions of oocytes showed fluorescein of zona pellucida after treatment with Con A (93%), LCA (93%) and RCA-I (100%) than BS-II (37%) and UEA-I (50%). All of the oocytes treated with RCA-I exhibited strong fluorescein in the outer region of the zona pellucida while those treated with LCA exhibited strong fluorescein throughout the zona pellucida. BS-II bounded mainly to the outer region and UEA-I bounded mainly to the inner region of the zona pellucida, with either strong or weak fluorescein. At 120 min after insemination in vitro, fewer spermatozoa were bound to the zona pellucida of the oocytes treated with BS-II, Con-A and RCA-I. Of the lectins, Con A most inhibited sperm binding. Conclusions: These results suggest that $\beta$-D-Galactose residues in the porcine zona pellucida may act as primary sperm receptors and inducers of the sperm acrosome reaction and these sugar residues may be involved in the block to polyspermy.

• BMB Reports
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• v.37 no.6
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• pp.715-719
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• 2004

The fate of Telfairia occidentalis seed Agglutinin, TOA, has been monitored during germination. While the level of the Agglutinin in the cotyledons decreased sharply in the first three days to about half of the initial level, it stabilises at this level for the following twelve days. In this interval, Agglutinin activity becomes manifest in the radicle on the fourth day, peaking on the fifth and decreasing rapidly thereafter. In the plumule, the lectin activity becomes manifest on the sixth day, peaks on the seventh and decreases rapidly thereafter. No lectin activity is detectable in any plant tissue including the rump of the cotyledons twenty-seven days after germination. The implications of these observations on the possible role of lectins in plants are discussed.

• YAKHAK HOEJI
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• v.47 no.3
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• pp.176-179
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• 2003

A library of unlimited number of novel lectins with diverse specificities has been previously generated by randomly mutating the carbohydrate-recognition domain of Maackia amurensis hemagglutinin (MAH). To establish the experimental environment capable of selecting high affinity mutant lectins in E. coli, phage display system was adapted. Carbohydrate binding capacity of two phagemid vectors, pComb3 and pComb8 displaying wild-type MAH lectin was assessed. Specific bindings of pComb3 and pComb8 phages expressing w.t. MAH to affinity-purified polyclonal anti-MAH antibody and to glycophorin was demonstrated. Both phages also showed strong hemagglutinating activity to intact but not sialidase-treated human erythrocytes, which is consistent to the specificity of native MAH. Taken together, two different phage display vectors successfully allowed the expression of active MAH as a fusion protein on the surface of bacteriophage, which will lead to preparation of unique plant lectins with high affinity toward a variety of carbohydrate chains.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.146-147
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• 2001

Lectins or carbohydrate-binding proteins are proteins of non-immune origin, which is able to agglutinate cells, and precipitate polysaccharides and glycoconjugates (Goldstein et al., 1980). Lectins with diverse physiological roles are widely distributed to the various plant, microorganisms, invertebrates and vertebrates. The ubiquitous occurrence of lectins in nature and their ability to recognize complementary sugars provided a stimulus for the continuous research for their biochemical properties and physiological functions (Raz and Lotan, 1987). (omitted)

• BMB Reports
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• v.35 no.5
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• pp.472-475
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• 2002

Phaseolus vulgaris phytohemagglutinin L is a homotetrameric-leucoagglutinating seed lectin. Its three-dimensional structure shows similarity with other members of the legume lectin family. The tetrameric form of this lectin is pH dependent. Gel filtration results showed that the protein exists in its dimeric state at pH 2.5 and as a tetramer at pH 7.2. Contrary to earlier reports on legume lectins that possess canonical dimers, thermal denaturation studies show that the refolding of phytohemagglutinin L at neutral pH is irreversible. Differential scanning calorimetry (DSC) was used to study the denaturation of this lectin as a function of pH that ranged from 2.0 to 3.0. The lectin was found to be extremely thermostable with a transition temperature around $82^{\circ}C$ and above $100^{\circ}C$ at pH 2.5 and 7.2, respectively. The ratio of calorimetric to vant Hoff enthalpy could not be calculated because of its irreversible-folding behavior. However, from the DSC data, it was discovered that the protein remains in its compact-folded state, even at pH 2.3, with the onset of denaturation occurring at $60^{\circ}C$.

• Archives of Pharmacal Research
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• v.27 no.1
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• pp.118-126
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• 2004

The aqueous extract of European mistletoe (Viscum album, L.) has been used in cancer therapy. The purified mistletoe lectins, main components of mistletoe, have demonstrated cytotoxic and immune-system-stimulating activities. Korean mistletoe (Viscum album L. coloratum), a subspecies of European mistletoe, has also been reported to possess anticancer and immunological activities. A galactose- and N-acetyl-D-galactosamine-specific lectin (Viscum album L. coloratum agglutinin, VCA) with Mr 60 kDa was isolated from Korean mistletoe. Mistletoe preparations have been given subcutaneously due to the low stability of lectin in the gastrointestinal (GI) tract. In the present study, we investigated the possibility of alginate/chitosan microcapsules as a tool for oral delivery of mistletoe lectin. In addition, our strategy has been to develop a system composed of stabilizing cores (granules), which contain mistletoe lectin, extract or powder, coated by a biodegradable polymer wall. Our results indicated that successful incorporation of VCA into alginate/chitosan microcapsules has been achieved and that the alginate/chitosan microcapsule protected the VCA from degradation at acidic pH values. And coating the VCA with polyacrylic polymers, Eudragit, produced outstanding results with ideal release profiles and only minimal losses of cytotoxicity after manufacturing step. The granules prepared with extract or whole plant produced the best results due to the stability in the extract or whole plant during manufacturing process.

• BMB Reports
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• v.28 no.1
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• pp.6-11
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• 1995

A new lectin, named TRA, was purified from Trichosanthes kirilowii root by acid-treated Sepharose 6B, Mono-Q, and TSK-gel 3000SW column sequential chromatography. The lectin appeared homogeneous by native gel electrophoresis at pH 4.3 and gave two protein bands of Mr=31 and 28 kDa by SDS-PAGE. The N-terminal amino acid sequences of the polypeptides of TRA have not been reported in amino acid sequences of the lectins. TRA lectin formed a precipitate with asialofetuin, neuraminidase-treated fetuin. A sugar inhibition assay indicated that N-acetyl-D-galactosamine, among the monosaccharides tested, was the most potent inhibitor of TRA-induced hemagglutination. Asialofetuin showed a 260-times stronger inhibitory activity than N-acetyl-D-galactosamine. TRA lectin also showed agglutination with normal leukocytes and lymphoma cells, but not with premature hemopoietic cells. These results suggest that TRA is a novel plant lectin.

• Journal of Pharmacopuncture
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• v.22 no.3
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• pp.122-130
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• 2019

Objectives: The medicinal plants are believed to enhance the natural resistance of the body to infections. Some of the main constituents of the plant and derived materials such as, proteins, lectins and polysaccharides have anti-inflammatory effects. Portulaca oleracea (P. oleracea) were used traditionally for dietary, food additive, spice and various medicinal purposes. This review article is focus on the anti-asthmatic effects of P. oleracea and its constituents. Methods: Various databases, such as the PubMed, Scopus, and Google Scholar, were searched the keywords including "Portulaca oleracea", "Quercetin", "Anti-inflammatory", "Antioxidant", "Cytokines", "Smooth muscle ", and " Relaxant effects " until the end of Jul 2018. Results: P. oleracea extracts and its constituents increased $IFN-{\gamma}$, IL-2, $IFN{\gamma}/IL-4$ and IL- 10/IL-4 ratio, but decreased secretion of $TNF-{\alpha}$, IL-4 and chemokines in both in vitro and in vivo studies. P. oleracea extracts and quercetin also signifcantly decreased production of NO, stimulated ${\beta}$-adrenoceptor and/or blocking muscarinic receptors in tracheal smooth muscles. Conclusion: P. oleracea extracts and quercetin showed relatively potent anti-asthmatic effects due to decreased production of NO, inflammatory cytokines and chemokines, reduced oxidant while enhanced antioxidant markers, and also showed potent relaxant effects on tracheal smooth muscles via stimulatory on ${\beta}$-adrenoceptor or/and blocking muscarinic receptors.