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Plant fungal diseases cause major problems for the global economy. Antimicrobial peptides have aroused great interest in the control of phytopathogens, as they are natural molecules and have a broad spectrum of inhibitory activity. Herein, we have tried to identify and characterize antimicrobial peptides present in fruits of Capsicum chinense and to evaluate their enzymatic and antifungal activities. The retained fraction obtained in the anion exchange chromatography with strong antifungal activity was subjected to molecular exclusion chromatography and obtained four fractions named G1, G2, G3, and G4. The 6.0-kDa protein band of G2 showed similarity with protease inhibitors type II, and it was able to inhibit 100% of trypsin and α-amylase activities. The protein band with approximately 6.5 kDa of G3 showed similarity with sequences of protease inhibitors from genus Capsicum and showed growth inhibition of 48% for Colletotrichum lindemuthianum, 49% for Fusarium lateritium, and 51% for F. solani and F. oxysporum. Additionally, G3 causes morphological changes, membrane permeabilization, and ROS increase in F. oxysporum cells. The 9-kDa protein band of G4 fraction was similar to a nsLTP type 1, and a protein band of 6.5 kDa was similar to a nsLTP type 2. The G4 fraction was able to inhibit 100% of the activities of glycosidases tested and showed growth inhibition of 35 and 50% of F. oxysporum and C. lindemuthianum, respectively. C. chinense fruits have peptides with antifungal activity and enzyme inhibition with biotechnological potential.

A chitosanase (CvCsn46) from Chromobacterium violaceum ATCC 12472 was produced in Escherichia coli, purified, and partially characterized. When subjected to denaturing polyacrylamide gel electrophoresis, the enzyme migrated as two protein bands (38 and 36 kDa apparent molecular masses), which were both identified as CvCsn46 by mass spectrometry. The enzyme hydrolyzed colloidal chitosan, with optimum catalytic activity at 50 °C, and two optimum pH values (at pH 6.0 and pH 11.0). The chitosanolytic activity of CvCsn46 was enhanced by some ions (Ca2+, Co2+, Cu2+, Sr2+, Mn2+) and DTT, whereas Fe2+, SDS and β-mercaptoethanol completely inhibited its activity. CvCsn46 showed a non-Michaelis-Menten kinetics, characterized by a sigmoidal velocity curve (R2 = 0.9927) and a Hill coefficient of 3.95. ESI-MS analysis revealed that the hydrolytic action of CvCsn46 on colloidal chitosan generated a mixture of low molecular mass chitooligosaccharides, containing from 2 to 7 hexose residues, as well as D-glucosamine. The chitosan oligomers generated by CvCsn46 inhibited in vitro the mycelial growth of Lasiodiplodia theobromae, significantly reducing mycelium extension and inducing hyphal morphological alterations, as observed by scanning electron microscopy. CvCsn46 was characterized as a versatile biocatalyst that produces well-defined chitooligosaccharides, which have potential to control fungi that cause important crop diseases.

The aim of the study was to assess the antihyperglycemic, antilipidemic, and antioxidant effects of a lectin isolated from Bryothamnion seaforthii (BSL), on rats with streptozotocin (STZ)-induced diabetes. The disease model was induced by low-dose injections of STZ. Diabetic rats were treated with NaCl 150 mM, metformin, and BSL at different concentrations. Blood collection was carried out at 0, 30, 60, 90, and 120 days after hyperglycemia confirmation via the assessment of seric glucose, total cholesterol, and triglycerides, assessment of the enzymatic levels of glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD), and the determination of insulin resistance by a homeostasis model of assessment-insulin resistance (HOMA-IR) as well as a homeostasis model of assessment of β-cells resistance (HOMA-β). The BSL-treated animals at all three concentrations showed a significant reduction in levels of glucose, cholesterol, total cholesterol, and triglycerides. Moreover, BSL increased the enzymatic activity of GPx and SOD. Index assessments of HOMA-IR and HOMA-β confirmed that BSL treatment significantly decreased insulin resistance and β-cell hypersecretion, respectively. In conclusion, BSL treatment might exert hypoglycemic and hypolipidemic effects, diminish insulin resistance, and ameliorate pancreatic β-cell function along with enzymatic activities toward oxidative stress caused by diabetes mellitus type 2 (T2DM).

A type II lectin, designated as DlyL2, was purified from Dioclea lasiophylla Mart. ex Benth seeds and some of its physicochemical properties determined. The lectin demonstrated specificity for α-lactose and N-acetyl- d -galactosamine and was able to interact with porcine stomach mucin. DlyL2 has 0.78 % carbohydrates in its composition, therefore can be considered a glycoprotein. In addition, its hemagglutinating activity remained stable at a temperature of 90 °C and in a pH range from 5 to 10. Metal chelation treatment did not affect DlyL2 activity suggesting it's not a metalloprotein. Dlyl2 showed an apparent mass of 31 kDa and average molecular mass of 26.371 kDa. Primary structure data could be generated from the partial amino acid sequence of DlyL2, with about 192 residues sequenced by a combination of Edman degradation and tandem mass spectrometry. The lectin is similar to other type II lectins from Diocleinae subtribe, as well as lectins derived from species of more ancient tribes of the Fabaceae family. In addition, DlyL2 exhibited no toxicity to Artemia sp. nauplii. The present study expands the knowledge about the specificity, structural and physicochemical properties of Diocleinae type II lectins.

A new lectin from Aplysia dactylomela eggs (ADEL) was isolated by affinity chromatography on HCl-activated Sepharose™ media. Hemagglutination caused by ADEL was inhibited by several galactosides, mainly galacturonic acid (Ka = 6.05 × 106 M−1). The primary structure of ADEL consists of 217 residues, including 11 half-cystines involved in five intrachain and one interchain disulfide bond, resulting in a molecular mass of 57,228 ± 2 Da, as determined by matrix-assisted laser desorption/ionization time of flight mass spectrometry. ADEL showed high similarity with lectins isolated from Aplysia eggs, but not with other known lectins, indicating that these lectins could be grouped into a new family of animal lectins. Three glycosylation sites were found in its polypeptide backbone. Data from peptide-N-glycosidase F digestion and MS suggest that all oligosaccharides attached to ADEL are high in mannose. The secondary structure of ADEL is predominantly β-sheet, and its tertiary structure is sensitive to the presence of ligands, as observed by CD. A 3D structure model of ADEL was created and shows two domains connected by a short loop. Domain A is composed of a flat three-stranded and a curved five-stranded β-sheet, while domain B presents a flat three-stranded and a curved four-stranded β-sheet. Molecular docking revealed favorable binding energies for interactions between lectin and galacturonic acid, lactose, galactosamine, and galactose. Moreover, ADEL was able to agglutinate and inhibit biofilm formation of Staphylococcus aureus, suggesting that this lectin may be a potential alternative to conventional use of antimicrobial agents in the treatment of infections caused by Staphylococcal biofilms.

Infections caused by Candida tropicalis have increased significantly worldwide in parallel with resistance to antifungal drugs. To overcome resistance novel drugs have to be discovered. The objective of this work was to purify and characterize a cysteine protease inhibitor from the seeds of the Amazon rainforest tree Cassia leiandra and test its inhibitory effect against C. tropicalis growth. The inhibitor, named ClCPI, was purified after ion exchange and affinity chromatography followed by ultrafiltration. ClCPI is composed of a single polypeptide chain and is not a glycoprotein. The molecular mass determined by SDS-PAGE in the absence or presence of β-mercaptoethanol and ESI-MS were 16.63 kDa and 18.362 kDa, respectively. ClCPI was stable in the pH range of 7.0–9.0 and thermostable up to 60 °C for 20 min. ClCPI inhibited cysteine proteases, but not trypsin, chymotrypsin neither alpha-amylase. Inhibition of papain was uncompetitive with a Ki of 4.1 × 10−7 M and IC50 of 8.5 × 10−7 M. ClCPI at 2.6 × 10−6 M reduced 50% C. tropicalis growth. ClCPI induced damages and morphological alterations in C. tropicalis cell surface, which led to death. These results suggest that ClCPI have great potential for the development of an antifungal drug against C. tropicalis.

A new mannose/N-acetyl- d glucosamine-specific lectin, named MaL, was purified from seeds of Machaerium acutifolium by precipitation with ammonium sulfate, followed by affinity and ion-exchange chromatography. MaL haemagglutinates either native rabbit erythrocytes or those treated with proteolytic enzymes. MaL is highly stable by the ability to maintain its haemagglutinating activity after exposure to temperatures up to 50 °C. The lectin haemagglutinating activity was optimum between pH 6.0 and 7.0 and inhibited after incubation with d -mannose and N-acetyl- d -glucosamine and α-methyl- d -mannopyranoside. MaL is a glycoprotein with relative molecular mass of 29 kDa (α-chain), 13 kDa (β-chain) and 8 kDa (γ-chain) with secondary structure composed of 3% α-helix, 44% β-sheet, 21% β-turn, and 32% coil. The orofacial antinociceptive activity of the lectin was also evaluated. MaL (0.03 mg mL−1) reduced orofacial nociception induced by capsaicin, an effect that occurred via carbohydrate recognition domain interaction, suggesting an interaction of MaL with the transient receptor potential cation channel subfamily V member 1 (TRPV1) receptor. Our results confirm the potential pharmacological relevance of MaL as an inhibitor of acute orofacial mediated by TRPV1.

Volatile organic compounds (VOCs) from the red seaweeds Pterocladiella capillacea and Osmundaria obtusiloba were obtained by static headspace extraction and then analyzed qualitatively by gas chromatography mass spectrometry (GC-MS) and quantitatively by gas chromatography (GC) equipped with a flame ionization detector (FID). In total, 31 constituents were identified in the two species of algae. In P. capillacea, among the 21 constituents (100%), the major ones were hexanal (50.4%), 2-pentylfuran (9.2%), and heptadecene (8.8%). In O. obtusiloba, of the 21 constituents (100%), the most representatives were heptadecene (57.3%), hexanal (20.5%), and 1-pentadecene (2.6%). This is the first report on the identification and quantification of VOCs in the Rhodophyta, P. capillacea and O. obtusiloba.

A partial cDNA sequence from Anacardium occidentale CCP 76 was obtained, encoding a GH19 chitinase (AoChi) belonging to class VI. AoChi exhibits distinct structural features in relation to previously characterized plant GH19 chitinases from classes I, II, IV and VII. For example, a conserved Glu residue at the catalytic center of typical GH19 chitinases, which acts as the proton donor during catalysis, is replaced by a Lys residue in AoChi. To verify if AoChi is a genuine chitinase or is a chitinase-like protein that has lost its ability to degrade chitin and inhibit the growth of fungal pathogens, the recombinant protein was expressed in Pichia pastoris, purified and biochemically characterized. Purified AoChi (45 kDa apparent molecular mass) was able to degrade colloidal chitin, with optimum activity at pH 6.0 and at temperatures from 30 °C to 50 °C. AoChi activity was completely lost when the protein was heated at 70 °C for 1 h or incubated at pH values of 2.0 or 10.0. Several cation ions (Al3+, Cd2+, Ca2+, Pb2+, Cu2+, Fe3+, Mn2+, Rb+, Zn2+ and Hg2+), chelating (EDTA) and reducing agents (DTT, β-mercaptoethanol) and the denaturant SDS, drastically reduced AoChi enzymatic activity. AoChi chitinase activity fitted the classical Michaelis-Menten kinetics, although turnover number and catalytic efficiency were much lower in comparison to typical GH19 plant chitinases. Moreover, AoChi inhibited in vitro the mycelial growth of Lasiodiplodia theobromae, causing several alterations in hyphae morphology. Molecular docking of a chito-oligosaccharide in the substrate-binding cleft of AoChi revealed that the Lys residue (theoretical pKa = 6.01) that replaces the catalytic Glu could act as the proton donor during catalysis.

Vicilins are 7S globulins which constitute the major seed storage proteins in leguminous species. Variant vicilins showing differential binding affinities for chitin have been implicated in the resistance and susceptibility of cowpea to the bruchid Callosobruchus maculatus . These proteins are members of the cupin superfamily, which includes a wide variety of enzymes and non-catalytic seed storage proteins. The cupin fold does not share similarity with any known chitin-biding domain. Therefore, it is poorly understood how these storage proteins bind to chitin. In this work, partial cDNA sequences encoding β-vignin, the major component of cowpea vicilins, were obtained from developing seeds. Three-dimensional molecular models of β-vignin showed the characteristic cupin fold and computational simulations revealed that each vicilin trimer contained 3 chitin-binding sites. Interaction models showed that chito-oligosaccharides bound to β-vignin were stabilized mainly by hydrogen bonds, a common structural feature of typical carbohydrate-binding proteins. Furthermore, many of the residues involved in the chitin-binding sites of β-vignin are conserved in other 7S globulins. These results support previous experimental evidences on the ability of vicilin-like proteins from cowpea and other leguminous species to bind in vitro to chitin as well as in vivo to chitinous structures of larval C. maculatus midgut.

A novel lectin present in Dioclea reflexa seeds (DrfL) was discovered and described in this study. DrfL was purified in a single step by affinity chromatography in a Sephadex G-50 column. The lectin strongly agglutinated rabbit erythrocytes and was inhibited by α-methyl-D-mannoside, D-mannose, and D-glucose. The hemagglutinating activity of DrfL is optimum at pH 5.0-7.0, stable up to 50 °C, and dependent on divalent cations. Similar to other lectins of the subtribe Diocleinae, the analysis by mass spectrometry indicated that DrfL has three chains (α, β, and γ) with masses of 25,562, 12,874, and 12,706 Da, respectively, with no disulfide bonds or glycosylation. DrfL showed inflammatory activity in the paw edema model and exhibited low cytotoxicity against Artemia sp.

Phase equilibrium of aqueous two-phase systems (ATPS) containing triblock copolymer, L64, (EO)13(PO)30(EO)13 and sulfate salts were investigated in this work. It was analyzed the effect of the temperature at 278.15 K to 298.15 K and type of salt. The rise of the temperature increased the slope of the tie line (STL). The sodium sulfate showed better capability to induce phase separation.

In this study, the amino acid sequence and anti-inflammatory effect of Bauhinia bauhinioides (BBL) lectin were evaluated. Tandem mass spectrometry revealed that BBL possesses 86 amino acid residues. BBL (1 mg/kg) intravenously injected in rats 30 min prior to inflammatory stimuli inhibited the cellular edema induced by carrageenan in only the second phase (21% – 3 h, 19% – 4 h) and did not alter the osmotic edema induced by dextran. BBL also inhibited carrageenan peritoneal neutrophil migration (51%), leukocyte rolling (58%) and adhesion (68%) and the neutrophil migration induced by TNF-α (64%). These effects were reversed by the association of BBL with galactose, demonstrating that the carbohydrate-binding domain is essential for lectin activity. In addition, BBL reduced myeloperoxidase activity (84%) and TNF-α (68%) and IL1-β (47%) levels. In conclusion, the present investigation demonstrated that BBL contains highly homologous isolectins, resulting in a total of 86 amino acid residues, and exhibits anti-inflammatory activity by inhibiting neutrophil migration by reducing TNF-α and IL1-β levels via the lectin domain. Copyright © 2015 John Wiley & Sons, Ltd.

A new lectin from the marine sponge Chondrilla caribensis (CCL) was isolated by affinity chromatography in Sepharose 6B media. CCL is a homotetrameric protein formed by subunits of 15,445 ±2Da. The lectin showed affinity for disaccharides containing galactose and mucin. Mass spectrometric analysis revealed about 50% of amino acid sequence of CCL, which showed similarity with a lectin isolated from Aplysina lactuca. Secondary structure consisted of 10% α-helix, 74% β-sheet/β-turn and 16% coil, and this profile was unaltered in a broad range of pH and temperatures. CCL agglutinated Staphylococcus aureus, S epidermidis and Escherichia coli, and it was able to reduce biofilm biomass, but showed no inhibition of planktonic growth of these bacteria. CCL activity was inhibited by α-lactose, indicating that Carbohydrate Recognition Domain (CRD) of the lectin was involved in antibiofilm activity.

Natural antioxidants found in marine macroalgae are bioactive compounds known to play an important role in the prevention of diseases associated with aging cells protecting them against the oxidative damage. The purpose of this study was to evaluate the antioxidant and cytotoxic activity of ethanolic extracts of two species of red seaweeds, Amansia multifida and Meristiella echinocarpa. In vitro antioxidant activity was determined by DPPH radical scavenging assay, ferric-reducing antioxidant power (FRAP) assay, ferrous ion chelating (FIC) assay, β-carotene bleaching (BCB) assay and total phenolic content (TPC) quantification. Cytotoxicity was evaluated with the brine shrimp Artemia sp. lethality test. The TPC values observed in the present study indicated that both species A. multifida and M. echinocarpa are rich in phenolic compounds, reaching values of 45.40 and 28.46 mg gallic acid equivalent (GAE) g−1 of ethanolic extract, respectively. DPPH radical scavenging and ferrous ion chelating showed values of 60% and 17%, respectively. Both seaweed extracts inhibited β-carotene oxidation by approximately 40%. None of the algal extracts were potentially cytotoxic. The results have showed that extracts of both species of marine red algae exhibit antioxidant potential and low toxicity. They are sources of natural antioxidant compounds. Antioxidantes naturais encontrados em macroalgas marinhas são substâncias bioativas conhecidas por desempenhar um papel importante na prevenção de doenças associadas com o envelhecimento, protegendo as células de danos oxidativos. O objetivo deste estudo foi avaliar as atividades antioxidante e citotóxica de extratos etanólicos de duas espécies de algas vermelhas, Amansia multifida e Meristiella echinocarpa. A atividade antioxidante in vitro foi determinada pela capacidade de sequestro do radical DPPH, o poder de redução do ferro (FRAP), o poder de quelação do íon ferroso (FIC), o teste de oxidação acoplada β-caroteno/ácido linoleico (BCB), bem como a quantificação do conteúdo fenólico total. A citotoxicidade foi avaliada pelo teste de letalidade contra Artemia sp. Os valores das substâncias fenólicas observados no presente estudo indicaram que as espécies A. multifida e M. echinocarpa são ricas em substâncias fenólicas, atingindo valores de 45,40 e de 28,86 mg de ácido gálico equivalente (AGE) g−1 de extrato etanólico, respectivamente. A capacidade de seqüestro do radical DPPH e o poder de quelação do íon ferroso foram 60% e 17%, respectivamente. Ambos os extratos algáceos inibiram a oxidação do β-caroteno em torno de 40%. Nenhum dos extratos algáceos foi potencialmente citotóxico. Os resultados mostraram que os extratos destas espécies de rodófitas apresentam potencial antioxidante e baixa toxicidade. Elas são fontes de compostos antioxidantes naturais.

A novel mannose/glucose-binding lectin from Canavalia virosa (designated as ConV) has been purified from seeds of C. virosa by affinity chromatography on a mannose-Sepharose 4B column. ConV strongly agglutinates rabbit erythrocytes and was inhibited by monosaccharides (D-mannose, D-glucose, and α-methyl-D-mannoside) and glycoproteins (ovalbumin and fetuin). SDS-PAGE revealed three bands corresponding to three subunits (α, β, and γ) confirmed by ESI mass spectrometry with exact mass of 25,480 ± 2 Da, 12,864 ± 1 Da, and 12,633 ± 1 Da, respectively. The purified lectin was more stable in pH ranging from 7.0 to 9.0, supported up to 80 ºC without any loss in activity and unaffected by EDTA. ConV showed no toxicity against Artemia sp. nauplii and relaxed endothelized rat aorta, with the participation of the lectin domain. In our tests, the lectin immobilized on CNBr-Sepharose was capable of binding 0.8 mg of ovalbumin per chromatography, allowing the use of ConV as a tool for capture and purification of glycoproteins.

Lectins are comprised of a large family of proteins capable of the specific and reversible recognition of carbohydrates. Legume lectins, the most studied plant lectins, show high structural similarity, but with modifications that imply a variation in the intensity of some biological activities. In this work, the primary and tertiary structures of Canavalia grandiflora (ConGF) were determined. ConGF, a lectin isolated from C. grandiflora seeds, is able to induce relaxant activity in rat aortic rings. The complete sequence of ConGF comprises 237 amino acids. This particular protein has primary sequence variations commonly found in lectins from Dioclea and Canavalia genera. The protein structure was solved at 2.3 Å resolution by X-ray crystallography. An X-Man molecule was modeled into the carbohydrate recognition domain. Still, ConGF (30 and 100 μg mL(-1)) elicited 25% of vasorelaxation (IC50=34.48 ± 5.07 μg mL(-1)) in endothelialized aortic rings. A nonselective inhibitor of nitric oxide blocked ConGF relaxant effect, showing mediation by nitric oxide. Key distances between ConGF carbohydrate recognition domain residues were determined in order to explain this effect, in turn revealing some structural aspects that could differentiate lectins from the Canavalia genera with respect to different efficacy in vasorelaxant effect.

Recent studies have shown that lectins are promising tools for use in various biotechnological processes, as well as studies of various pathological mechanisms, isolation, and characterization of glycoconjugates and understanding the mechanisms underlying pathological mechanisms conditions, including the inflammatory response. This study aimed to purify, characterize physicochemically, and predict the biological activity of Canavalia oxyphylla lectin (CoxyL) in vitro and in vivo. CoxyL was purified by a single-step affinity chromatography in Sephadex® G-50 column. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that the pure lectin consists of a major band of 30 kDa (α-chain) and two minor components (β-chain and γ-chain) of 16 and 13 kDa, respectively. These data were further confirmed by electrospray ionization mass spectrometry, suggesting that CoxyL is a typical ConA-like lectin. In comparison with the average molecular mass of α-chain, the partial amino acid sequence obtained corresponds to approximately 45% of the total CoxyL sequence. CoxyL presented hemagglutinating activity that was specifically inhibited by monosaccharides (D-glucose, D-mannose, and α-methyl-D-mannoside) and glycoproteins (ovalbumin and fetuin). Moreover, CoxyL was shown to be thermostable, exhibiting full hemagglutinating activity up to 60°C, and it was pH-sensitive for 1 h, exhibiting maximal activity at pH 7.0. CoxyL caused toxicity to Artemia nauplii and induced paw edema in rats. This biological activity highlights the importance of lectins as important tools to better understand the mechanisms underlying inflammatory responses.

A new lectin from the marine sponge Haliclona caerulea (H-3) was isolated using a combination of hydrophobic interaction chromatography and ion-exchange chromatography. H-3 is a protein with three distinct bands on SDS-PAGE: 9 kDa, 16 kDa and 18 kDa. Nevertheless, on gel filtration and N-PAGE, H-3 showed a symmetrical peak and a unique band, respectively. Hemagglutinating activity of H-3 was stable at neutral pH and temperatures up to 60 °C. N-Acetylgalactosamine and porcine stomach mucin were the most potent inhibitors of H-3. Primary structure of the lectin was determined using tandem mass spectrometry, and it showed no similarity to any members of the animal lectin families. Top down fragmentation revealed some posttranslational modifications in H-3, including glycosylation. The glycan composition of H-3 was determined, and its structure was predicted. Furthermore, H-3 is a blue protein, binding to a chromophore(-597) by weak interactions, and this is the first time that the interaction between one lectin and a natural chromophore has been shown.

Lectin from the seeds of Dioclea lasiophylla (DlyL) was purified in a single step by affinity chromatography on a Sephadex (R) G-50 column. DlyL strongly agglutinated rabbit erythrocytes and was inhibited by monosaccharides (D-mannose and alpha-methyl-D-mannoside) and glycoproteins (ovalbumin and fetuin). Similar to other Diocleinae lectins, DlyL has three chains, alpha, beta and gamma, with mass of 25,569 +/- 2, 12,998 +/- 1 and 12,588 +/- 1 Da, respectively, and has no disulfide bonds. The hemagglutinating activity of DlyL was optimal in pH 8.0, stable at a temperature of 70 degrees C and decreased in EDTA solution, indicating that lectin activity is dependent on divalent metals. DlyL exhibited low toxicity on Artemia sp. nauplii, but this effect was dependent on the concentration of lectin in solution. DlyL immobilized on cyanogen bromide-activated Sepharose (R) 4B bound 0.917 mg of ovalbumin per cycle, showing the ability to become a tool for glycoproteomics studies.

Indole-3-acetic acid (IAA) bound is considered a storage molecule and is inactive. However, some studies have proposed an additional possible regulatory mechanism based on the ability of lectins to form complexes with IAA. We report the first crystal structure of ConM in complex with IAA at 2.15 Å resolution. Based on a tetrameric model of the complex, we hypothesize how the lectin controls the availability of IAA during the early seedling stages, indicating a possible new physiological role for these proteins. A free indole group is also bound to the protein. The ConM interaction with different forms of IAA is a strategy to render the phytohormone unavailable to the cell. Thus, this new physiological role proposed for legume lectins might be a novel mechanism by which IAA levels are decreased in addition to the destruction and formation of new complexes in the later stages of seed germination.

Vatairea guianensis seeds, a typical plant from the Brazilian Amazon region that belongs to the Dalbergieae tribe, possess a lectin that was isolated by precipitation with solid ammonium sulfate followed by guar gum affinity chromatography. This lectin was named VGL. The V. guianensis lectin strongly agglutinated rabbit erythrocytes and was inhibited by d -galactose and d -galactose-derived sugars, especially N-acetyl- d -galactosamine. VGL has been shown to be a stable protein, maintaining its hemagglutinating activity after incubation at a wide range of temperature and pH values and after incubation with ethylenediamine tetraacetic acid (EDTA). In a sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, the purified VGL exhibited an electrophoretic profile consisting of a major 30–32 kDa double band, which is termed the alpha-chain, and two minor components of 18 and 15 kDa, which are referred to as the beta- and gamma-chains, respectively. An analysis using electrospray ionization mass spectrometry also indicated that purified VGL contains a mixture of chains with molecular weights of 28,437 ± 2, 14,952 ± 2 and 12,332 ± 2. The complete amino acid sequence of VGL, as determined using tandem mass spectrometry, consists of 239 amino acid residues. VGL is a glycoprotein exhibiting high similarity in primary structure to other lectins from evolutionarily related plants, such as Vatairea macrocarpa lectin and lectins belonging to the Sophoreae tribe. VGL exhibits vasorelaxant activity in contracted rat aortas, an effect that is strictly dependent on the endothelium and involves nitric oxide and the lectin domain.

A lectin from seeds of Dioclea lasiocarpa (DLL) was purified in a single step by affinity chromatography in a Sephadex G-50 column. DLL haemagglutinated rabbit erythrocytes showing stability even after 1 h of exposure to a different pH values (optimal between pH 6.0 and 8.0) but was inhibited after incubation with d-mannose and d-glucose. The pure protein possessed a molecular weight of 25 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis and 25,410Da by mass spectrometry. The results analyzed by the software SELCON 3 indicate that β-sheet secondary structures are predominant in DLL (approximately 40.2% antiparallel β-sheet, 4.6% parallel β-sheet, 7.2% α-helices, 17.3% turns, and 28.7% unordered structures). Mechanical activity of isolated aorta from rat measured by cumulative concentration curves of DLL, performed at the contraction plateau induced by phenylephrine in either endothelium-intact or denuded aorta. DLL (IC50 = 34.12 ± 3.46 µg/ml) relaxed precontracted endothelized aortic rings by 34.61 ± 9.06%, 55.19 ± 11.9%, and 81.33 ± 14.35%, respectively, at 10 µg/ml (initial concentration), 30 µg/ml, and 100 µg/ml (maximum effect). All effects occurred via interaction with lectin domains and participation of nitric oxide. Copyright © 2012 John Wiley & Sons, Ltd.

The Abelmoschus esculentus (Malvaceae) plant originated in Africa and has spread across a number of tropic countries, including northeastern Brazil. The plant has been used to treat various disorders, such as cancer, microbial infections, hypoglycemia, constipation, urine retention and inflammation. The lectin of A. esculentus (AEL) was isolated by precipitation with ammonium sulfate at a saturation level of 30/60 and purified by ion exchange chromatography (Sephacel-DEAE). The electrophoresis (SDS-PAGE) profile of the AEL showed two protein bands of apparent molecular mass of approximately 15.0 and 21.0 kDa. The homogenity of the protein was confirmed by electrospray mass spectrometry (ESI-MS), which revealed the presence of a 10.29-kDa monomer and a 20.58-kDa dimer. The AEL exhibits agglutinating activity against rabbit (74.41 UH/mP) and human type ABO erythrocytes (21.00 UH/mP). This activity does not require the presence of divalent cations and is specifically inhibited by lactose, fructose and mannose. The intravenous treatment with 0.01, 0.1 and 1 mg/kg of AEL inhibited the paw edema elicited by carrageenan by approximately 15, 22 and 44 %, respectively, but not that induced by dextran. In addition, treatment with 0.1, 1 and 10 mg/kg of AEL also inhibited the abdominal writhing induced by acetic acid by approximately 52, 57 and 69 %, respectively. In conclusion, AEL is a new lectin with a molecular mass of 20.0 kDa, which is -composed of a 10.291-Da monomer and a 20.582-kDa dimer, that exhibits anti-inflammatory, antinociceptive and hemagglutinating activities. In addition, the lectin hemagglutinating property is both metallo-independent and associated with the lectin domain.

DwL, a lectin extracted from the seeds of Dioclea wilsonii, is a metalloprotein with strong agglutinating activity against rabbit and ABO erythrocytes, inhibited by glucose and mannose. DwL was purified by affinity chromatography on a Sephadex G-50 column and ion exchange chromatography on a HiTrap SP XL column. SDS-PAGE revealed three electrophoretic bands corresponding to the α (25,634 ± 2 Da), β (12,873 ± 2 Da) and γ (12,779 ± 2 Da) chains. Protein sequencing was done by Tandem Mass Spectrometry. The primary sequence featured 237 amino acids and was highly homologous to other reported Diocleinae lectins. A complete X-ray dataset was collected at 2.0 Å for X-Man-complexed DWL crystals produced by the vapor diffusion method. The crystals were orthorhombic and belonged to the space group I222, with the unit-cell parameters a = 59.6, b = 67.9 and c = 109.0 Å. DWL differed in potency from other ConA-like lectins and was found to induce neutrophil migration in rats, making it particularly useful in structural/functional studies of this class of proteins.

The legume species of Cymbosema roseum of Diocleinae subtribe produce at least two different seed lectins. The present study demonstrates that C. roseum lectin I (CRL I) binds with high affinity to the "core" trimannoside of N-linked oligosaccharides. Cymbosema roseum lectin II (CRL II), on the other hand, binds with high affinity to the blood group H trisaccharide (Fuc1,2Gal1-4GlcNAc-). Thermodynamic and hemagglutination inhibition studies reveal the fine binding specificities of the two lectins. Data obtained with a complete set of monodeoxy analogs of the core trimannoside indicate that CRL I recognizes the 3-, 4- and 6-hydroxyl groups of the (1,6) Man residue, the 3- and 4-hydroxyl group of the (1,3) Man residue and the 2- and 4-hydroxyl groups of the central Man residue of the trimannoside. CRL I possesses enhanced affinities for the Man5 oligomannose glycan and a biantennary complex glycan as well as glycoproteins containing high-mannose glycans. On the other hand, CRL II distinguishes the blood group H type II epitope from the Lewisx, Lewisy, Lewisa and Lewisb epitopes. CRL II also distinguishes between blood group H type II and type I trisaccharides. CRL I and CRL II, respectively, possess differences in fine specificities when compared with other reported mannose and fucose recognizing lectins. This is the first report of a mannose-specific lectin (CRL I) and a blood group H type II-specific lectin (CRL II) from seeds of a member of the Diocleinae subtribe. © 2011 The Author.

A lectin-like protein from the seeds of Acacia farnesiana was isolated from the albumin fraction, characterized, and sequenced by tandem mass spectrometry. The albumin fraction was extracted with 0.5 M NaCl, and the lectin-like protein of A. farnesiana (AFAL) was purified by ion-exchange chromatography (Mono-Q) followed by chromatofocusing. AFAL agglutinated rabbit erythrocytes and did not agglutinate human ABO erythrocytes either native or treated with proteolytic enzymes. In sodium dodecyl sulfate gel electrophoresis under reducing and nonreducing conditions, AFAL separated into two bands with a subunit molecular mass of 35 and 50 kDa. The homogeneity of purified protein was confirmed by chromatofocusing with a pI = 4.0 +/- 0.5. Molecular exclusion chromatography confirmed time-dependent oligomerization in AFAL, in accordance with mass spectrometry analysis, which confers an alteration in AFAL affinity for chitin. The protein sequence was obtained by a liquid chromatography quadrupole time-of-flight experiment and showed that AFAL has 68% and 63% sequence similarity with lectins of Phaseolus vulgaris and Dolichos biflorus, respectively.

The agglutinin from the red marine alga Hypnea cervicornis (HCA) was tested in models of nociception and inflammation. The role of carbohydrate-binding sites and the systemic toxicity were assessed. HCA (10(-1), 1, and 10 mg/kg) administered i.v. to mice inhibited writhes induced by acetic acid and, at 10 mg/kg, inhibited the second phase of the formalin test, but did not alter the response latency in the hot-plate test. HCA (1 mg/kg) administered i.v. to rats reduced carrageenan-induced paw edema at 1, 2, and 3 h after challenge, but not edema induced by dextran. The neutrophil migration induced by both N-formyl-methionyl-leucyl-phenylalanine (fMLP) and carrageenan was inhibited by HCA at 10(-1), 1, and 10 mg/kg. The combination of HCA (1 mg/kg) and its ligand mucin reversed the lectin inhibitory effect on carrageenan-induced neutrophil migration and acetic acid-induced writhes. The i.v. treatment of rats with HCA (1 mg/kg) for 7 days did not affect body mass; liver, kidney or heart wet weight; blood leukocyte counts; urea, creatinine or serum transaminase activity; or macroscopy of the organs examined. In short, H. cervicornis agglutinin showed important antinociceptive and anti-inflammatory activity via interaction with the lectin carbohydrate-binding site.

Twenty species of marine invertebrates from the Brazilian coast were screened for hemagglutinating/hemolytic activity. In at least twelve tested species, hemagglutinating activity was different for different blood types, suggesting the presence of lectins. Extracts from four species showed hemolytic activity. Two new lectins were purified from the marine sponge Cliona varians (CvL-2) and sea cucumber Holothuria grisea (HGL). CvL-2 was able to agglutinate rabbit erythrocytes and was inhibited by galactosides. The hemagglutinating activity was optimal in pH neutral and temperatures below 70 °C. CvL-2 is a trimeric protein with subunits of 175 kDa. On the other hand, HGL showed both hemagglutinating and hemolytic activity in human and rabbit erythrocytes, but hemolysis could be inhibited by osmotic protection, and agglutination was inhibited by mucin. HGL was stable in pH values ranging from 4 to 10 and temperatures up to 90 °C. In electrophoresis and gel filtration, HGL was a monomeric protein with 15 kDa. CvL-2 and HGL showed different levels of toxicity to Artemia naplii. CvL-2 showed LC50 of 850.1 μg/mL, whereas HGL showed LC50 of 9.5 µg/mL. Vinte espécies de invertebrados marinhos, coletados na costa brasileira, foram avaliados quanto à presença de atividade hemaglutinante/hemolítica. Em pelo menos doze espécies testadas, a atividade hemaglutinante foi diferencial para diferentes grupos sanguíneos, sugerindo a presença de lectinas. Extratos de quatro espécies apresentaram atividade hemolítica. Duas novas lectinas foram purificadas da esponja marinha Cliona varians (CvL-2) e do pepino-domar Holothuria grisea (HGL). CvL-2 foi capaz de aglutinar eritrócitos de coelho e foi inibida por galactosídeos. A atividade hemaglutinante foi estável em pH neutro e temperaturas abaixo de 70 °C. CvL-2 é uma proteína trímero com subunidades de 175 kDa. Por outro lado, HGL apresentou atividade hemaglutinante e hemolítica em eritrócitos humanos e de coelho, mas a hemólise pôde ser inibida por proteção osmótica, enquanto que a aglutinação foi inibida por mucina. HGL mostrou-se estável em valores de pH de 4-10 e temperaturas até 90 °C. Em eletroforeses e gel filtração, HGL foi uma proteína monômero de 15 kDa. CvL-2 e HGL mostraram diferentes níveis de toxicidade contra náuplios de Artemia. CvL-2 apresentou LC50 de 850,1 μg/mL, enquanto que HGL apresentou LC50 de 9,5 μg/mL.

Parkia platycephala lectin 2 was purified from Parkia platycephala (Leguminosae, Mimosoideae) seeds by affinity chromatography and RP-HPLC. Equilibrium sedimentation and MS showed that Parkia platycephala lectin 2 is a nonglycosylated monomeric protein of molecular mass 29 407+/-15 Da, which contains six cysteine residues engaged in the formation of three intramolecular disulfide bonds. Parkia platycephala lectin 2 agglutinated rabbit erythrocytes, and this activity was specifically inhibited by N-acetylglucosamine. In addition, Parkia platycephala lectin 2 hydrolyzed beta(1-4) glycosidic bonds linking 2-acetoamido-2-deoxy-beta-D-glucopyranose units in chitin. The full-length amino acid sequence of Parkia platycephala lectin 2, determined by N-terminal sequencing and cDNA cloning, and its three-dimensional structure, established by X-ray crystallography at 1.75 A resolution, showed that Parkia platycephala lectin 2 is homologous to endochitinases of the glycosyl hydrolase family 18, which share the (betaalpha)8 barrel topology harboring the catalytic residues Asp125, Glu127, and Tyr182.

The crystal structures of the apo and mannose-bound Parkia platycephala seed lectin represent the first structure of a Mimosoideae lectin and a novel circular arrangement of beta-prism domains, and highlight the adaptability of the beta-prism fold as a building block in the evolution of plant lectins. The P.platycephala lectin is a dimer both in solution and in the crystals. Mannose binding to each of the three homologous carbohydrate-recognition domains of the lectin occurs through different modes, and restrains the flexibility of surface-exposed loops and residues involved in carbohydrate recognition. The planar array of carbohydrate-binding sites on the rim of the toroid-shaped structure of the P.platycephala lectin dimer immediately suggests a mechanism to promote multivalent interactions leading to cross-linking of carbohydrate ligands as part of the host strategy against phytopredators and pathogens. The cyclic structure of the P.platycephala lectin points to the convergent evolution of a structural principle for the construction of lectins involved in host defense or in attacking other organisms.

A lectin from the red marine alga Hypnea musciformis (HML) was purified by extraction with 20 mM PBS, precipitation with 70% saturated ammonium sulphate, ion-exchange DEAE-Cellulose chromatography and RP-HPLC. The 9.3 kDa polypeptide agglutinates erythrocytes from various sources and shows oligomerization tendencies under certain MALDI-TOF/MS conditions. Preliminary N-terminal sequencing and biological assays strongly suggest that the HML may belong to a new class of algae lectins.

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.

A chitin-binding protein named PPL-2 was purified from Parkia platycephala seeds and crystallized. Crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 55.19, b = 59.95, c = 76.60 A, and grew over several days at 293 K using the hanging-drop method. Using synchrotron radiation, a complete structural data set was collected to 1.73 A resolution. The preliminary crystal structure of PPL-2, determined by molecular replacement, presents a correlation coefficient of 0.558 and an R factor of 0.439. Crystallographic refinement is in progress.

A novel lectin, HGA-2, was isolated from the sea cucumber Holothuria grisea . The protein was isolated by a single chromatographic step using a column of Guar Gum as affinity. HGA-2 showed an apparent molecular mass of 17 kDa and 34 kDa under reducing and nonreducing conditions, respectively. The hemagglutinating activity was specific for rabbit erythrocytes, showing no activity for human blood A, B and O. Its hemagglutinating activity was inhibited by carbohydrates containing galactose, with higher affinity for GalNAc and glycoprotein porcine stomach mucin (PSM). HGA-2 was stable at pH 6–10, significantly declining at pH 5 and a temperature of 40 °C, with its activity being abolished at 100 °C. The HGA-2 protein was found to be Ca 2+ -dependent; it was highly toxic against Artemia nauplii and able to recognize and agglutinate cells of Escherichia coli . Amino acid sequences of tryptic peptides of HGA-2 strongly suggest that HGA-2 is a member of the C-type lectin family.

More than 120 years ago, Peter Hermann Stillmark in his doctoral thesis presented in 1888 to the University of Dorpat, gave the earliest step in the study of proteins that have a very interesting feature: the ability to agglutinate erythrocytes. These proteins were initially referred as to hemagglutinins or phytoagglutinins, since they were originally isolated from extracts of plants [1]. The first hemagglutinin isolated by Stillmark was extracted from seeds of the castor tree (Riccinus communis) and was named ricin [2]. This hemagglutinin was strongly used by Paul Ehrlich as model antigens for immunological studies [2,3].

The unique carbohydrate-binding property of lectins makes them invaluable tools in biomedical research. Here, we report the purification, partial primary structure, carbohydrate affinity characterization, crystallization, and preliminary X-ray diffraction analysis of a lactose-specific lectin from Cymbosema roseum seeds (CRLII). Isolation and purification of CRLII was performed by a single step using a Sepharose-4B-lactose affinity chromatography column. The carbohydrate affinity characterization was carried using assays for hemagglutination activity and inhibition. CRLII showed hemagglutinating activity toward rabbit erythrocytes. O-glycoproteins from mucine mucopolysaccharides showed the most potent inhibition capacity at a minimum concentration of 1.2 microg mL(-1). Protein sequencing by mass spectrometry was obtained by the digestion of CRLII with trypsin, Glu-C, and AspN. CRLII partial protein sequence exhibits 46% similarity with the ConA-like alpha chain precursor. Suitable protein crystals were obtained with the hanging-drop vapor-diffusion method with 8% ethylene glycol, 0.1 M Tris-HCl pH 8.5, and 11% PEG 8,000. The monoclinic crystals belong to space group P2(1) with unit cell parameters a = 49.4, b = 89.6, and c = 100.8 A.

The structural ground underlying the pH-dependency of the dimer–tetramer transition of Diocleinae lectins was investigated by equilibrium sedimentation and X-ray crystal structure determination of wild-type and site-directed mutants of recombinant lectins. Synthetic genes coding for the full-length α-chains of the seed lectins of Dioclea guianensis (termed r-αDguia) and Dioclea grandiflora (termed r-αDGL) were designed and expressed in Escherichia coli. This pioneering approach, which will be described in detail in the present paper, yielded recombinant lectins displaying carbohydrate-binding activity, dimer–tetramer equilibria and crystal structures indistinguishable from their natural homologues. Conversion of the pH-stable tetrameric r-αDGL into a structure exhibiting pH-dependent dimer–tetramer transition was accomplished through mutations that abolished the interdimeric interactions at the central cavity of the tetrameric lectins. Both the central and the peripheral interacting regions bear structural information for formation of the canonical legume lectin tetramer. We hypothesize that the strength of the ionic contacts at these sites may be modulated by the pH, leading to dissociation of those lectin structures that are not locked into a pH-stable tetramer through interdimeric contacts networking the central cavity loops.

The crystallization and preliminary X-ray diffraction analysis of the seed lectin of Parkia platycephala, a Mimosoideae, regarded as the most primitive group of the Leguminosae plants, are reported. Its amino-acid sequence consists of three tandemly arranged jacalin-related beta-prism domains, which is a novel fold for a leguminous lectin. Furthermore, no other lectin structure with this arrangement of domains has been described. P2(1)2(1)2(1) crystals (unit-cell parameters a = 63.6, b = 68.5, c = 208.5 A), which diffract to a maximum resolution of 2.2 A, were obtained in hanging drops at pH 8 and 293 K by the vapor-diffusion method using 10% 2-propanol and 20% polyethylene glycol 4000 as precipitants. The asymmetric unit contains two lectin molecules and has a solvent content of 46%. Only a single beta-prism domain could be located by molecular replacement using the structure of the Helianthus tuberosus lectin (PDB code 1c3k) as the search model. Isomorphous heavy-atom derivatives are currently being produced to solve the complete structure of the P. platycephala seed lectin.

An l -rhamnose-binding lectin named ELEL was isolated from eggs of the rock boring sea urchin Echinometra lucunter by affinity chromatography on lactosyl-agarose. ELEL is a homodimer linked by a disulfide bond with subunits of 11 kDa each. The new lectin was inhibited by saccharides possessing the same configuration of hydroxyl groups at C-2 and C-4, such as l -rhamnose, melibiose, galactose and lactose. The amino acid sequence of ELEL was determined by tandem mass spectrometry. The ELEL subunit has 103 amino acids, including nine cysteine residues involved in four conserved intrachain disulfide bonds and one interchain disulfide bond. The full sequence of ELEL presents conserved motifs commonly found in rhamnose-binding lectins, including YGR, DPC and KYL. A three-dimensional model of ELEL was created, and molecular docking revealed favorable binding energies for interactions between ELEL and rhamnose, melibiose and Gb 3 (Galα1-4Galβ1-4Glcβ1-Cer). Furthermore, ELEL was able to agglutinate Gram-positive bacterial cells, suggesting its ability to recognize pathogens.

Lectins are proteins that specifically bind to carbohydrates and form complexes with molecules and biological structures containing saccharides. The FRIL (Flt3 receptor interacting lectin) is a dimeric two-chain (αβ)2 lectin presenting 67 kDa molecular mass. The interaction of FRIL with carbohydrates, as determined by molecular docking, showed that this lectin has highest affinity to the carbohydrate trimannoside (−135.618 MDS), followed by trehalosamine (−127.072 MDS) and αα-trehalose (−121.729 MDS). FRIL evoked dose-dependent paw edema, increasing animal paw volumes. The edematogenic effect of FRIL was paralleled by an increase in vascular permeability, about 10-fold higher compared to control. FRIL also significantly raised the animals flinch reaction in the first, third and fifth hours in response to mechanical stimulation. Injection of α-methyl- d -mannoside associated with FRIL inhibited edema and hypernociception. The histopathological analysis of animal paws showed a characteristically acute inflammatory process that included severe infiltration of mixed leukocytes, changes in cytoarchitecture, edema and focal areas of hemorrhage. In addition, in silico assays confirmed that FRIL preferentially interacts with trimannoside that makes up the core N -glycans cell. Therefore, our study supports the hypothesis that the lectin domain and the likely glycoconjugates containing α- d -methyl mannoside residues contribute to the inflammatory effects of FRIL.

A new galactose-specific lectin, named BBL, was purified from seeds of Bauhinia bauhinioides by precipitation with ammonium sulfate, followed by two steps of ion exchange chromatography. BBL haemagglutinated rabbit erythrocytes (native and treated with proteolytic enzymes) showing stability even after exposure to 60 °C for one hour. The lectin haemagglutinating activity was optimum between pH 8.0 and 9.0 and inhibited after incubation with D-galactose and its derivatives, especially α-methyl-D-galactopyranoside. The pure protein possessed a molecular mass of 31 kDa by SDS – PAGE and 28.310 Da by mass spectrometry. The lectin pro-inflammatory activity was also evaluated. The s.c. injection of BBL into rats induced a dose-dependent paw edema, an effect that occurred via carbohydrate site interaction and was significantly reduced by L-NAME, suggesting an important participation of nitric oxide in the late phase of the edema. These findings indicate that BBL can be used as a tool to better understand the mechanisms involved in inflammatory responses.

Andira anthelmia seeds, a species belonging to the Leguminosae family, Papilionoideae subfamily, Dalbergieae tribe, have a glucose/mannose specific lectin that agglutinates rabbit erythrocytes treated with trypsin. The Dalbergieae tribe has lectins which have specificity for different carbohydrates including mannose and also have several biological activities such as induction of rat paw edema, release of chemotactic mediators by macrophages, vasorelaxant effect in rat aortas, termiticide activity, potential fungicide action, among others. This study aimed to isolate, purify and physicochemically characterize a lectin found in seeds of Andira anthelmia. The lectin from Andira anthelmia seeds was purified by affinity chromatography on Mannose-Sepharose matrix followed by ion exchange chromatography on DEAE-Sephacel matrix. This procedure resulted in a purified lectin, named AAL. AAL purification process was monitored by specific hemagglutinating activity and SDS-PAGE, in which it was observed that this lectin has a molecular weight of approximately 20 kDa and four others subunits of approximately 15 and 14 kDa. This lectin is a glycoprotein with approximately 1.89% of carbohydrates on its composition and shows high stability, being able to maintain their hemagglutinating activity in a wide pH range and after exposure to temperatures of 70 °C for one hour. After dialysis against the chelating agent EDTA, AAL lost its hemagglutinating activity, but recovered its action after the addition of metals, being, therefore, dependent on divalent metal cations. In this study a new lectin from Dalbergieae was purified and characterized. Further analyzes are needed in order to best evaluate their biotechnological applications.