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PubMed1991

Purification and Characterization of Two Major Lectins from Araucaria brasiliensis syn. Araucaria angustifolia Seeds (Pinhão).

Two major lectins (lectin I and lectin II) were purified to homogeneity from the seeds of Araucaria brasiliensis (Gymnospermae). The purity of the lectins was confirmed by polyacrylamide gel electrophoresis, isoelectric focusing, and high performance liquid chromatography. They are glycoproteins in nature containing 6.3 and 2.9%, respectively, of neutral sugar and have absorption coefficients of 3.8 and 4.7, respectively, at 280 nanometers. The molecular weights of both lectins obtained by gel filtration on Sephacryl S-400 were equal: 200,000. After dissociation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, molecular weights were 20,000 and 34,000, respectively, for lectin I and lectin II, suggesting they are decameric and hexameric in nature. The amino acid composition of both lectins showed little difference, but both had high amounts of acidic amino acids and lacked methionine in their molecule. The carbohydrate binding specificity of lectins was directed towards mannose, glucose, and their oligomers. High inhibitory activity was also found with thyroglobulin. The erythroagglutinating activity of the lectins was enhanced in the presence of high-molecular-weight substances both at 37 and 4 degrees C. Divalent cations do not appear to be essential for activity. They maintained their agglutinating activity over a broad but different range of pH: 5.5 to 7.5 and 6.5 to 7.5, respectively. Both lectins agglutinated erythrocytes of human ABO blood types equally well.

Journal Article↗

PubMed1992

The 14 kDa beta-galactoside binding lectin in myoblast and myotube cultures: localization by confocal microscopy.

The endogenous 14 kDa beta-galactoside-specific lectin has been localised in myoblasts and myotubes by indirect immunofluorescence using confocal microscopy. The antibodies used in these experiments suggest that in myoblast cultures the lectin is abundant on the cell surface and concentrated at ruffled edges of migrating cells. The quantity and distribution of cell surface lectin is independent of the nature of the substratum and undiminished by brief trypsinisation or lactose-washing of the cell suspension. The lectin is also abundant intracellularly, apparently relatively free in the cytoplasm until the cells approach confluency, when the lectin is concentrated into particular areas of cytoplasm resulting in a 'patchy' appearance of stained cells. After fusion to form multinucleate myotubes, intracellular lectin is less abundant and concentrated at the periphery of myotubes, from where lectin appears to be released in vesicles packed with lectin which 'bud off' from the myotube surface. In recolonising cultures, lectin is apparently more abundant and lectin-packed vesicles can also be seen 'budding off' from myoblasts. In differentiated cultures, extracellular lectin is detected both on the myotube surface and in fibrillar arrays of extracellular material.

3T3 Cells↗

PubMed2003

Isolation of a beta-galactoside-binding lectin from cat liver.

A lectin from cat liver has been identified and purified by affinity chromatography on asialofetuin-Sepharose. One hundred micrograms of lectin was obtained from one cat liver with a purification factor of 1561. The lectin agglutinates trypsin-treated rabbit and cow erythrocytes. Hemagglutination was inhibited only by saccharides containing -galactosyl residues, of which the 1-amine-1-deoxy- -D-galactose was the most potent one by inhibiting hemagglutination at a concentration of 12.5 mM, followed by melibiose, trehalose and galactose. The lectin has a subunit molecular mass of 14.4 kDa determined by SDS-PAGE under reducing conditions and a pI of 4.85. Compared with the composition of lectins from calf heart and porcine heart, cat liver lectin contains approximately the same amount of cysteine, half the amount of glycine, twice as much arginine and threonine, and three times the amounts of tyrosine and methionine. Cat liver lectin contains four cysteine residues per subunit, all of them in the reduced form. Their lack of reactivity towards thiol-reactive supports suggests they are not exposed on the lectin surface. The protein apparently has a blocked N-terminus. The purified lectin was stable for up to 20 months stored at +4 C in buffer supplemented with 4 mM -mercaptoethanol. Results indicated that this lectin belongs to the family of soluble -galactoside-binding lectins, also known as galectins, which are expressed in a wide range of vertebrate tissues.

Animals↗

PubMed1992

DNA polymerase alpha, beta, and gamma activities in human lymphocytes stimulated by Tora-mame (Phaseolus vulgaris) lectin.

We measured the levels of the DNA polymerases alpha, beta, and gamma in human peripheral lymphocyte cells stimulated with Tora-mame lectin (TM-lectin) and the induction patterns were compared to those with other plant lectins, i.e., phytohemagglutinin (PHA) and pokeweed mitogen (PWM). The maximum activity of DNA polymerase alpha in lymphocytes was achieved at the concentration of 10 micrograms/ml with TM lectin and the dose response curve of TM lectin showed a sharp peak in contrast to that of PWM. During prolonged stimulation for 10 days, the time course of DNA polymerase alpha induction was different among these three lectins. A peak of alpha-enzyme was correlated with maximal incorporation of [3H]thymidine and was observed on the fourth day with TM lectin, on the third day with PHA, and sixth day with PWM. DNA polymerase beta in lymphocytes was also activated by the addition of these proteins. Two different peaks were observed during a 10-day period with every lectin, and TM lectin was most potent stimulator among them. The activity of DNA polymerase gamma in lymphocytes was at a very low but detectable level which increased slightly in response to TM lectin treatment. Although some variability of gamma-enzyme activity was observed after the seventh day, the pattern in the course of 7 days was similar among the lectins.

Cells, Cultured↗

PubMed2001

Opposite effects on human colon cancer cell proliferation of two dietary Thomsen-Friedenreich antigen-binding lectins.

Increased cell surface expression of the Thomsen-Friedenreich antigen (TF antigen, Galbeta1-3GalNAcalpha-) is a common feature in malignant and pre-malignant epithelia. Our previous studies have shown that dietary TF-binding lectins from peanut (Arachis hypogea) and edible mushroom (Agaricus bisporus) produce marked but different effects on human intestinal epithelial cell proliferation. This study investigates the proliferative effects of the other two known dietary TF-binding lectins: jacalin (Artocarpus integrifolia, JAC) and amaranth lectin (Amaranthus caudatus, ACA). JAC produced dose-dependent and non-cytotoxic inhibition of proliferation in HT29 human colon cancer cells with maximal effects of 46 +/- 4% at 20 microg/ml, whereas ACA produced dose-dependent stimulation of proliferation with maximal effects of 22 +/- 3% at 20 microg/ml when assessed both by incorporation of [3H]thymidine into DNA and by cell counting. The lectin-mediated effects were inhibitable by the presence of appropriate Galbeta1-3GalNAc-expressing glycoproteins but differences existed between JAC and ACA in their patterns of inhibition by such substances. Ligand binding equilibrium studies using iodinated lectins revealed different Kd of the two lectins for HT29 cell surface glycoproteins. Lectin blots of cell membrane extracts showed different binding patterns in all the four TF-binding lectins. These results provide further evidence that dietary TF-binding lectins can have marked effects on the proliferation of human malignant gastro-intestinal epithelial cells and hence may play a role in intestinal cancer development, and also show that the biological effects of dietary lectins cannot be predicted solely from their carbohydrate binding properties.

Adjuvants, Immunologic↗

PubMed2000

Biological effects of natural and recombinant mistletoe lectin and an aqueous mistletoe extract on human monocytes and lymphocytes in vitro.

Mistletoe lectin is thought to constitute the active principle in extract preparations from mistletoe, which are widely used as immunomodulators in adjuvant tumor therapy. However, no study exists which compares the immunological potency of different well-defined mistletoe lectin preparations on human immune cells. Therefore, in the present study the biological effects of an aqueous mistletoe extract, standardized for mistletoe lectin I (eML), the isolated natural mistletoe lectin (nML), and the recombinant form of this lectin (rML) on human peripheral blood monocytes and lymphocytes were compared with respect to cell viability and cytokine induction. After 48-hr incubation of peripheral blood mononuclear cells (PBMC) with rML, nML, and eML, a continuous concentration-dependent decrease in cell viability was found with an IC50 of about 3 ng/ml for rML and nML and 10 ng/ml for eML, respectively. This effect also was seen when isolated lymphocytes and monocytes were separately incubated with the lectin preparations. After incubation of PBMC and isolated monocytes of 5/10 blood donors with eML, an increase in cell viability was found at lectin concentrations between 10 and 1,000 pg/ml. This effect was not seen with the pure lectin preparations nML and rML. After 48-hr incubation of PBMC with rML, nML, and eML, induction of IL-1-beta, TNF-alpha, IL-2, IL-6, and IL-10 but not IFN-gamma was measured. For IL-1-beta it could be shown that cytokine induction took place at a broad lectin concentration range (0.1-100 ng/ml). Cytokine levels varied greatly in the PBMC cultures of the different blood donors. When monocytes were separately incubated with eML, nML, and rML for 48 hr, high levels of IL-1-beta were found. In contrast, in cultures of separated lymphocytes from the same donors only a minimal production of IL-1-beta and no production of IFN-gamma was found after incubation with rML, nML, and eML. It is concluded that there are quantitative differences in the immunomodulatory effects of the mistletoe lectin preparations on human monocytes and lymphocytes. Therefore, measurement of cell viability and cytokine induction may be a diagnostic laboratory tool to determine the immunological potency of various mistletoe preparations and may help to clarify the clinical benefit of therapies with these substances.

Adult↗

PubMed1989

Microscopic and biochemical characterization of lectin binding sites in the cephalopod retina.

Using light and electron microscope cytochemistry and lectin blotting techniques, we have shown that the lectins concanavalin A (Con A), Ricinus communis agglutinin (RCA), and peanut agglutinin (PNA) bind to specific glycoconjugants in the adult cephalopod retina. For light microscope lectin cytochemistry, aldehyde-fixed, frozen, or Araldite-embedded, etched sections of cephalopod retinas were incubated with FITC- or TRITC-conjugated lectins and examined by using epifluorescence microscopy. Con A labeled structures in the entire retina including the inner limiting membrane (ILM), rhabdomeric membranes, interphotoreceptor matrix (IPM), and structures in the photoreceptor inner segments. RCA labeling was similar to that of Con A except that there was a decrease in the staining of the rhabdom tips near the ILM. PNA labeled only the interphotoreceptor matrix between apposing rhabdomeres. The intensity of staining of the IPM by PNA also decreased or was absent toward the rhabdom tips. None of the lectins labeled the myeloid bodies located in the photoreceptor inner segments. Electron microscope (EM) lectin cytochemistry was performed on aldehyde-fixed, LR White-embedded tissue or on Araldite-embedded, periodate-etched sections by using gold-conjugated lectins. EM results confirmed the observations made by light microscopy. Lectin blots with a retinal extract or light-sensitive membrane fraction revealed a variety of protein bands labeled by all three lectins. Con A and RCA labeled opsin and its aggregates whereas PNA did not. None of the lectins labeled retinochrome. The labeling of the cephalopod IPM by PNA suggests a structural similarity between the IPM of vertebrates and invertebrates. In other studies, we have demonstrated the presence of a retinoid binding protein in the IPM of cephalopods.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1983

Agglutination of murine and guinea pig peritoneal cells by alpha-L-fucose-binding lectin: Evonymus europaea.

Among lectins from Lotus tetragonolobus, Ulex europaeus I and Evonymus europaea, agglutinating cells with blood group H determinants containing L-fucose alpha 1 leads to 2-linked to subterminal D-galactose, only the last lectin agglutinates thioglycolate- and paraffin oil-stimulated murine and guinea pig peritoneal exudate cells (PEC). The agglutination is inhibited by specific inhibitors of Evonymus lectin only: lacto-N-fucopentaose I and lactose. These results suggest the presence of a determinant on the surface of PEC, containing L-fucose alpha 1-linked at the nonreducing end which is different from blood group H determinants. Nonstimulated murine peritoneal cells (PC) are not agglutinated by the lectin but become agglutinable after neuraminidase treatment. Unstimulated guinea pig PC from different animals are agglutinated to a different extent by the same lectin concentration and show increased agglutinability after neuraminidase digestion. These results show that receptor for Evonymus lectin also exists on the nonstimulated PC but access to it is hindered by sialic acid. Trypsin- and pronase-digested PEC show increased agglutinability with Evonymus lectin. These results suggest that the lectin receptor is a glycolipid. Since alpha-linked L-fucose has been suggested as a part of the macrophage receptor for migration inhibitory factor in the guinea pig (Remold, J. Exp. Med. 1973. 138: 1065), the effect of Evonymus europaea lectin on the migration of PEC was studied. It was found that lectin inhibits the migration of PEC in the capillary tube assay up to 80%.

Agglutination↗

PubMed1995

Isolation and characterization of Cajanus cajan lectin.

Cajanus cajan lectin was isolated by ammonium sulfate fractionation and affinity chromatography on an IgM-Sepharose 6B column. Gel filtration and SDS-PAGE showed size homogeneity of the lectin. The lectin with M(r) 18,000 on SDS-PAGE had gel filtration behavior which was consistent with a molecular weight of 39 kDa and a Stokes radius of 2.74 nm. The results showed that the lectin is a dimer composed of identical subunits with N- and C-terminal residues of threonine and alanine, respectively. The glycoprotein lectin contained 3% concanavalin A-reactive neutral carbohydrates. Its amino acid composition is characterized by high contents of acidic amino acids. The number of tyrosine and tryptophan residues per mole of the lectin was determined to be 14 and 4, respectively, by spectrophotometry. Results on the effects of large numbers of saccharides on lectin-mediated hemagglutination and lectin-IgM precipitation showed that the C. cajan lectin was specific for mannose and glucose. A comparative study of the properties of C. cajan lectin and concanavalin A is also presented.

Amino Acids↗

PubMed1982

Histochemical study of Hurler's disease by the use of peroxidase-labelled lectins.

Peroxidase-labelled lectins specific for various carbohydrate residues were used as histochemical reagents in the investigation of Hurler's syndrome. Peanut lectin was used to detect terminal D-galactose, wheatgerm lectin for N-acetyl-D-glucosamine, soybean lectin for N-acetyl-D-galactosamine, Tetragonolobus lotus lectin for alpha-L-fucose and Bandeiraea S. lectin for alpha-D-galactose. It was found that Kupffer cells in the liver and splenic reticulo-endothelial cells contain acid mucopolysaccharides which bind lectins in paraffin sections after appropriate fixation. The pattern of lectin binding suggests that such cells contain significant amounts of D-galactose, L-fucose, N-acetyl-D-galactosamine and N-acetyl-D-glucosamine. It is likely that the last named carbohydrate is present as a polymer. Neurones contain a different carbohydrate, rich in galactose and fucose but poor in N-acetyl-D-glucosamine. This compound is resident to lipid extraction. Hepatocytes, as a rule, do not react with lectins, most likely because of loss of the more soluble mucopolysaccharides during fixation. The results are consistent with the biochemical data of Hurler's syndrome and indicate that lectins can be a useful tool for the investigation of the cytochemistry of storage disorders.

Child↗

PubMed2002

Lectin-binding by sporozoites of Elmeria tenella.

Sporozoites of Eimeria tenella were reacted in vitro with 19 different lectins characterized with a variety of carbohydrate-binding properties. Nine lectins caused sporozoite agglutination, which was inhibited by the specific carbohydrates mannose, sialic acid, melibiose, D-galactose, or D-galNAc. When intact live or fixed whole sporozoites were reacted with fluorescein isothiocyanate-conjugated lectins, another nine lectins bound to sporozoites, giving weak to strong fluorescence but not agglutination. Of these, all nine lectins bound to surface sites, but four also bound to the refractile body. Two of the agglutinating lectins also bound to intracellular organelles of air-dried sporozoites. SDS-PAGE analysis showed that biotinylated lectins bound a wide variety of parasite proteins. Lectins with similar carbohydrate specificities had some similarity in binding patterns of parasite proteins, as well as marked differences. In a few cases lectins with different carbohydrate specificities bound common protein bands. Only one lectin (Dolichos biflorus) showed no evidence of binding to whole sporozoites, organelles, or proteins.

Acetylgalactosamine↗

PubMedDate not supplied

IgA binding lectins isolated from distinct Artocarpus species demonstrate differential specificity.

The discovery of jacalin, a group of lectins from jackfruit seeds (Artocarpus heterophyllus), has attracted considerable attention due to its numerous interesting immunological properties as well as its usefulness in the isolation of various serum proteins. We have further identified a similar lectin from the seeds of Champedak (Artocarpus integer) which we refer to as lectin-C and performed comparative studies with two types of jacalin isolated from different batches of the Malaysian jackfruit seeds (jacalin-M1 and jacalin-M2). The three purified lectins demonstrated equivalent apparent Mr of about 52,500, each of which comprised of a combination of two types of non-covalently-linked subunits with apparent Mr of approximately 13,300 and 16,000. The lectins demonstrated equal haemagglutinating activity against human erythrocytes of blood groups A, B, AB and O. Our data also demonstrated that lectin-C, jacalin-M1 and jacalin-M2 are similar by selectively precipitating human serum IgA1 and colostral sIgA but not IgA2, IgD, IgG and IgM. When immunoelectrophoresis was performed on normal human sera and reacted with the lectins, single precipitin arcs corresponding to IgA immunoprecipitates were detected with lectin-C and jacalin-MI. Jacalin-M2, however, exhibited two closely associated precipitin arcs. The binding of these lectins with IgA was pronouncedly inhibited in the presence of p-nitrophenyl-beta-D-galactopyranoside, 1-o-methyl-alpha-D-galactopyranoside, D-melibiose, N-acetyl-D-galactosamine and D-galactose. The data therefore provide evidence on the differential specificity of IgA binding lectins isolated from seeds of similar as well as distinct Artocarpus species.

Binding, Competitive↗

PubMed2001

Cloning of cDNAs encoding C-type lectins from Elapidae snakes Bungarus fasciatus and Bungarus multicinctus.

A number of C-type lectins with various biological activities have been purified and characterized from Viperidae snake venoms. In contrast, only a few reports could be found in literature concerning the C-type lectins in Elapidae snake venoms. Based on the published cDNA sequences of C-type lectins from Viperidae snake venoms, oligonucleotide primers were designed and used to screen the cDNA libraries made from the venom glands of Bungarus fasciatus and Bungarus multicinctus. This allowed the cloning of three full length cDNAs encoding C-type lectins. The encoded proteins, named BFL-1, BFL-2 and BML, exhibit high degrees of sequence identities with Viperidae snake venom saccharide-binding lectins (around 60% with Trimeresurus stejnegeri venom lectin, Crotalus atrox venom lectin and Agkistrodon piscivorus venom lectin). They show much less identities with other venom C-type lectin-like proteins (around 30% with the platelet glycoprotein Ib-binding protein from Agkistrodon blomhoffi venom and the factor IX/X-binding protein from Trimeresurus flavoviridis venom). The cDNAs revealed that the precursors contain potential signal peptides characterized by a hydrophobic core. To our knowledge, these are the first cDNA cloning of group VII C-type lectins (Drickamer K. 1993. Prog. Nucleic Acid Res. Mol. Biol. 45, 207-232) from Elapidae snake venom glands.

Animals↗

PubMed2001

Mannose-binding plant lectins: different structural scaffolds for a common sugar-recognition process.

Mannose-specific lectins are widely distributed in higher plants and are believed to play a role in recognition of high-mannose type glycans of foreign micro-organisms or plant predators. Structural studies have demonstrated that the mannose-binding specificity of lectins is mediated by distinct structural scaffolds. The mannose/glucose-specific legume (e.g., Con A, pea lectin) exhibit the canonical twelve-stranded beta-sandwich structure. In contrast to legume lectins that interact with both mannose and glucose, the monocot mannose-binding lectins (e.g., the Galanthus nivalis agglutinin or GNA from bulbs) react exclusively with mannose and mannose-containing N-glycans. These lectins possess a beta-prism structure. More recently, an increasing number of mannose-specific lectins structurally related to jacalin (e.g., the lectins from the Jerusalem artichoke, banana or rice), which also exhibit a beta-prism organization, were characterized. Jacalin itself was re-defined as a polyspecific lectin which, in addition to galactose, also interacts with mannose and mannose-containing glycans. Finally the B-chain of the type II RIP of iris, which has the same beta-prism structure as all other members of the ricin-B family, interacts specifically with mannose and galactose. This structural diversity associated with the specific recognition of high-mannose type glycans highlights the importance of mannose-specific lectins as recognition molecules in higher plants.

Binding Sites↗

PubMed1998

Isolation and characterization of a novel lectin from Dioclea lehmanni (Fabaceae) seeds.

Dioclea lehmanni seeds are known to contain two lectins [G. Pérez, M. Hernández, E. Mora, Isolation and characterization of a lectin from the seeds of Dioclea lehmanni, Phytochemistry 29 (1990) 1745-1749]. Taking advantage of the strong bond shown by one of them (Dioclea lehmanni lectin I) to Sephacryl S-200, it has been purified and characterized as a Glc/Man lectin very similar to Concanavalin A. In order to compare the properties of the two lectins, we purified the second one (Dioclea lehmanni lectin II) to homogeneity by gel filtration and hydrophobic chromatography. Dioclea lehmanni lectin II is a dimeric protein (58.4 kDa) with identical subunits with M(r) = 29,000. Its molecular properties, carbohydrate specificity, human and animal erythroagglutination pattern, amino acid composition and N-terminal sequence (27 residues) were determined. These features clearly distinguish lectin II from lectin I; therefore a second novel lectin is present in the seeds of Dioclea lehmanni.

Amino Acid Sequence↗

PubMed1993

Crystal structure determination and refinement at 2.3-A resolution of the lentil lectin.

We report on the X-ray structure determination of the orthorhombic crystal form of lentil lectin by molecular replacement using the pea lectin coordinates as a starting model. The structure was refined at 2.3-A resolution with a combination of molecular dynamics refinement and classical restrained least-squares refinement. The final R value for all data Fo > 1 sigma (Fo) between 7.0- and 2.3-A resolution is 0.164%, and deviations from ideal bond distances are 0.014 A. The C-terminus of the beta-chain proved to be 23 amino acids longer than found in previous studies. This together with several inconsistencies between the previously determined amino acid sequence and the observed electron density forced a redetermination of the amino acid sequence of the protein. The overall structure is very similar to that of pea lectin and isolectin I of Lathyrus ochrus, the most prominent deviations being confined to loop regions and the regions of intermolecular contact. The largest difference between the pea and lentil lectin monomers is situated in the loop region of amino acids 73-79 of the beta chain. There are no significant differences between the two crystallographic independent lentil lectin monomers in the asymmetric unit. The model includes 104 well-defined water molecules, of which a significant number have a counterpart in the pea lectin structure. As for the other legume lectins, each lentil lectin monomer contains one calcium ion in a highly conserved environment. On the contrary, the manganese binding sites are distorted with respect to the pea lectin and concanavalin A structures. The Asp beta 121 side chain apparently does not ligate the Mn2+ ion. This difference is consistent in both lentil lectin monomers and agrees with earlier solution studies. Possible implications for oligosaccharide binding are discussed.

Amino Acid Sequence↗

PubMed1997

Isolation, characterization and molecular cloning of a leaf-specific lectin from ramsons (Allium ursinum L.).

Lectins were isolated from roots and leaves of ramsons and compared to the previously described bulb lectins. Biochemical analyses indicated that the root lectins AUAIr and AUAIIr are identical to the bulb lectins AUAI and AUAII, whereas the leaf lectin AUAL has no counterpart in the bulbs. cDNA cloning confirmed that the leaf lectin differs from the bulb lectins. Northern blot analysis further indicated that the leaf lectin is tissue-specifically expressed. Sequence comparisons revealed that the ramsons leaf lectin differs considerably from the leaf lectins of garlic, leek, onion and shallot.

Allium↗

PubMed2001

The amino-acid sequence of the glucose/mannose-specific lectin isolated from Parkia platycephala seeds reveals three tandemly arranged jacalin-related domains.

A mannose/glucose-specific lectin was isolated from seeds of Parkia platycephala, the most primitive subfamily of Leguminosae plants. The molecular mass of the purified lectin determined by mass spectrometry was 47 946 +/- 6 Da (by electrospray ionization) and 47 951 +/- 9 Da (by matrix-assisted laser-desoption ionization). The apparent molecular mass of the lectin in solutions of pH in the range 4.5-8.5 determined by analytical ultracentrifugation equilibrium sedimentation was 94 +/- 3 kDa, showing that the protein behaved as a non-pH-dependent dimer. The amino-acid sequence of the Parkia lectin was determined by Edman degradation of overlapping peptides. This is the first report of the primary structure of a Mimosoideae lectin. The protein contained a blocked N-terminus and a single, nonglycosylated polypeptide chain composed of three tandemly arranged homologous domains. Each of these domains shares sequence similarity with jacalin-related lectin monomers from Asteraceae, Convolvulaceae, Moraceae, Musaceae, Gramineae, and Fagaceae plant families. Based on this homology, we predict that each Parkia lectin repeat may display a beta prism fold similar to that observed in the crystal structure of the lectin from Helianthus tuberosus. The P. platycephala lectin also shows sequence similarity with stress- and pathogen-upregulated defence genes of a number of different plants, suggesting a common ancestry for jacalin-related lectins and inducible defence proteins.

Amino Acid Sequence↗