RESUMO
Lectins are a class of proteins or glycoproteins capable of recognizing and interacting with carbohydrates in a specific and reversible manner. Owing to this property, these proteins can interact with glycoconjugates present on the cell surface, making it possible to decipher the glycocode, as well as elicit biological effects, such as inflammation and vasorelaxation. Here, we report a structural and biological study of the mannose/glucose-specific lectin from Dioclea lasiophylla seeds, DlyL. The study aimed to evaluate in detail the interaction of DlyL with Xman and high-mannose N-glycans (MAN3, MAN5 and MAN9) by molecular dynamics (MD) and the resultant in vitro effect on vasorelaxation using rat aortic rings. In silico analysis of molecular docking was performed to obtain the initial coordinates of the DlyL complexes with the carbohydrates to apply as inputs in MD simulations. The MD trajectories demonstrated the stability of DlyL over time as well as different profiles of interaction with Xman and N-glycans. Furthermore, aortic rings assays demonstrated that the lectin could relax pre-contracted aortic rings with the participation of the carbohydrate recognition domain (CRD) and nitric oxide (NO) when endothelial tissue is preserved. These results confirm the ability of DlyL to interact with high-mannose N-glycans with its expanded CRD, supporting the hypothesis that DlyL vasorelaxant activity occurs primarily through its interaction with cell surface glycosylated receptors.Communicated by Ramaswamy H. Sarma.
Assuntos
Dioclea , Animais , Carboidratos/química , Dioclea/química , Dioclea/metabolismo , Lectinas , Manose/química , Simulação de Acoplamento Molecular , Lectinas de Plantas/análise , Lectinas de Plantas/química , Lectinas de Plantas/farmacologia , Polissacarídeos/farmacologia , Ratos , Sementes/química , Sementes/metabolismo , Vasodilatadores/análise , Vasodilatadores/química , Vasodilatadores/farmacologiaRESUMO
Lectins are carbohydrate binding proteins with many physiological and biotechnological applications. Isolation of proteins is normally time-consuming and encompasses multiple and, sometimes, complicated steps that hinder reproducibility and yield. Affinity chromatography is an efficient way to simplify and improve protein purification, however often requiring an expensive and fragile stationary phase. In this regard, automated flow-based systems minimize the time for extraction of species from solid samples without hindering the features of batch procedures. In this work, a new inexpensive affinity-based stationary phase was developed for in-line separation of jacalin, a galactose-binding lectin from jackfruit seeds. In the flow manifold, in-line extraction of proteins was also carried out with continuous monitoring using the spectrophotometric Biuret assay. For protein determination, linear response was observed from 3.0 to 15â¯gâ¯L-1. The results of the analysis of protein extracts from jackfruit seeds obtained with the herein described procedure and batch procedure agreed with 95% confidence level. Quantitative extraction of proteins from jackfruit seed powder required recirculation of extraction buffer for 15â¯min through a lab-made polymethylmethacrylate (PMMA) column containing 200â¯mg of the crude seed powder. In the chromatographic step, jacalin was isolated after 300â¯s. Therefore, three essential steps for jacalin isolation were performed in one manifold in a fast way, minimizing sample consumption and solution handling. Additionally, the versatile and multi-task developed flow manifold can be useful for routine analysis and preparative procedures, being adaptable for the extraction and separation of other species from solid matrixes with continuous monitoring of the processes.
Assuntos
Fracionamento Químico/métodos , Cromatografia de Afinidade/métodos , Lectinas de Plantas , Proteínas de Plantas/isolamento & purificação , Artocarpus/química , Lectinas de Plantas/análise , Lectinas de Plantas/química , Lectinas de Plantas/isolamento & purificação , Proteínas de Plantas/análise , Proteínas de Plantas/química , Projetos de Pesquisa , Sementes/químicaRESUMO
There are numerous poisonous plants that can induce intralysosomal accumulation of glycoproteins and neurologic syndromes. Here we describe for the first time, a disease caused by ingesting Sida rodrigoi Monteiro in goats in North-western Argentina. The animals showed weight loss, indifference to the environment, unsteady gait and ataxia. Histopathologic studies showed vacuolization in cells of various organs, mainly in the CNS. The material deposited in the cells was positive for LCA (Lens culinaris agglutinin), WGA (Triticum vulgaris agglutinin), sWGA (succinyl-Triticum vulgaris agglutinin) and Con-A (Concanavalia ensiformis agglutinin) lectins. Finally, toxic levels of swansonine were identified in the plant. The present investigation allowed to recognize S. rodrigoi Monteiro poisoning as a plant induced α-mannosidosis.
Assuntos
Doenças das Cabras/diagnóstico , Malvaceae/química , Intoxicação por Plantas/veterinária , Swainsonina/toxicidade , alfa-Manosidose/veterinária , Ração Animal/análise , Animais , Argentina , Ataxia/diagnóstico , Ataxia/etiologia , Ataxia/veterinária , Sistema Nervoso Central/fisiopatologia , Dieta/veterinária , Doenças das Cabras/etiologia , Cabras , Lectinas de Plantas/análise , Intoxicação por Plantas/diagnóstico , Intoxicação por Plantas/etiologia , Plantas Tóxicas/química , alfa-Manosidose/diagnóstico , alfa-Manosidose/etiologiaRESUMO
Lectins have been described as glycoproteins that reversibly and specifically bind to carbohydrates. Legume lectins isolated from the subtribe Diocleinae (Canavalia, Dioclea andCratylia) are structurally homologous with respect to their primary structures. The Diocleinae lectins of Canavalia brasiliensis, Dioclea guianensis andCanavalia ensiformis have been shown to distinctly alter physiological parameters in isolated rat kidneys. Thus, the aim of this study was to investigate the effect of Cratylia floribunda lectin (CFL) on renal hemodynamics and ion transport in rats. In isolated perfused kidneys, CFL (10 mg/mL, n=5) increased RPP, RVR and decreased %TK+, but did not change urinary flow, glomerular filtration rate, sodium or chloride tubular transport. In isolated perfused mesenteric bed, CFL (3 and 10 mg/mL/min; n=4) did not alter tissue basal tonus or tissue contraction by phenylephrine (1 mM/mL/min). In conclusion, the seed lectin of Cratylia floribunda increased renal hemodynamic parameters showing a kaliuretic effect. This effect could be of tubular origin, rather than a result from haemodynamic alterations.
As lectinas são descritas como (glico)proteínas que se ligam, especificamente e reversivelmente, a carboidratos. Lectinas de leguminosas isoladas da subtribo Diocleinae (Canavalia, Dioclea eCratylia) são estruturalmente homólogas em relação às suas estruturas primárias. Demonstrou-se que as lectinas de DiocleinaeCanavalia brasiliensis, Dioclea guianensis eCanavalia ensiformis alteram diferentemente parâmetros fisiológicos em rins isolados de ratos. Dessa maneira, o objetivo deste estudo foi investigar o papel da lectina de Cratylia floribunda (CFL) na hemodinâmica renal e no transporte de íons em ratos. Em rins isolados perfundidos, CFL (10 mg/mL, n=5) aumentou a pressão de perfusão renal, a resistência vascular renal e reduziu o percentual do transporte tubular de K+, mas não alterou o fluxo urinário, a taxa de filtração glomerular e o percentual de transporte tubular dos íons sódio e cloreto. No leito mesentérico isolado perfundido, CFL (3 e 10 mg/mL/min, n=4) não alterou o tônus basal ou a contração do tecido induzida por fenilefrina (1 mM/mL/min). Em conclusão, a lectina de sementes de Cratylia floribunda altera parâmetros hemodinâmicos renais, provavelmente de origem tubular, e não por alterações hemodinâmicas.
Assuntos
Ratos , Transporte de Íons , Lectinas de Plantas/análise , Dioclea , Hemodinâmica , Amilorida/análiseRESUMO
Lectinas são proteínas cuja principal característica é a de se ligar específica e reversivelmente a carboidratos. BanLec é a lectina presente na polpa de bananas, que se liga especificamente a manose e glicose, e é capaz de induzir a proliferação de células T, podendo estimular a resposta imune. Existem indícios de que o teor de BanLec pode variar dependendo do estádio de amadurecimento e do tipo de cultivar, o que pode afetar a quantidade de BanLec existente na fruta quando consumida in natura e a possível resposta imune frente ao consumo de banana. Por este motivo, um dos objetivos desse trabalho foi determinar os teores e a atividade hemaglutinante de BanLec em extratos de farinha de banana verde, além de bananas das cultivares Pacovan, Figo, Terra, Mysore e Nanicão, nos estádios de maturação verde e maduro, e submetidas a tratamento com 1-MCP e baixa temperatura (para cv. Nanicão). Com vista a atender ao objetivo de avaliar seus efeitos imunomoduladores in vivo, a BanLec foi purificada da cultivar Nanicão e administrada por via oral a camundongos BALB/c. Os ensaios de atividade hemaglutinante dos extratos de banana apontaram para maior quantidade de BanLec no fruto maduro, quando comparado ao verde, e ausência dessa proteína na cultivar Figo. Os parâmetros imunológicos analisados após administração de BanLec aos camundongos demonstram que a resposta imune gerada após ingestão de BanLec é dose dependente, além disso, a administração de 50 µg de BanLec aos animais foi capaz de modular citocinas importantes na resposta imunológica, provavelmente causando um efeito que pode ser interpretado como mais protetor do que patogênico. Com base nos resultados obtidos, podemos concluir que existem diferenças nos teores de BanLec dependendo da cultivar e estádio de maturação analisado, sendo que essa proteína não está presente na polpa de todas as variedades de banana e finalmente, que ela tem grande potencial imunomodulador in vivo, uma vez que ativou citocinas de resposta anti-inflamatória
Lectins are proteins which bind specifically and reversibly to carbohydrates. BanLec is the lectin present in banana pulp, and it binds to mannose and glucose, being capable of inducing T-cell proliferation, and to stimulate the immune response. There are some evidence that the amount of BanLec may vary depending on the maturation stage of the fruit and the cultivar (cv.), which may affect the amount of BanLec and the possible immune response after consumption of banana. Thus, this study aimed to evaluate the amount of BanLec and its hemagglutinating activity in crude extracts of bananas from cultivars Pacovan, Figo, Terra, Mysore and Nanicão, in both unripe and ripe maturation stage, and also fruits which were treated with 1-MCP and low temperature. In addition, in order to access their immunomodulatory effects in vivo, BanLec was purified by affinity chromatography and administered orally to BALB/c mice. The hemagglutinating activity assays indicate higher amount of BanLec in ripe fruit. Moreover, the possible was undetectable in the pulp of banana Figo. The immunological parameters of mice orally fed with BanLec showed that the immunological response is dependent on the amount of protein administrated, in agreement to previous in vitro studies. Besides, 50 µg of BanLec, were able to modulate some cytokines in immune response, causing an effect that seems to be more protective than pathogenic. We conclude that there are important differences in amount of BanLec depending on the cultivar and the maturation stage, and BanLec has a dose-dependent immunomodulatory effect in vivo
Assuntos
Musa/imunologia , Lectinas de Plantas/análise , Imunomodulação/imunologia , Fatores Imunológicos/farmacologia , Bioquímica , Testes Imunológicos , Análise de Alimentos/métodosRESUMO
Parkia pendula (Willd.) Walp. (Fabaceae) is a neotropical species of the genus Parkia more abundantly distributed in Central to South America. From the seeds of P. pendula a glucose/mannose specific lectin (PpeL) was isolated that has been characterised and used as a biotechnological tool but until now this is the first manuscript to analyse P. pendula mRNA expression in seedlings. For this porpoise a Differential display reverse transcription polimerase chain reaction (DDRT-PCR) was used to evaluate the expression of P. pendula lectin mRNAs in non-rooted seedlings. No bands were observed in the agarose gel, indicating the absence of mRNA of PpeL seedlings. our findings confirm that lectins mRNAs are differently regulated among species even if they are grouped in the same class.
Assuntos
Fabaceae/genética , Lectinas de Plantas/genética , RNA Mensageiro/análise , RNA de Plantas/análise , Fabaceae/química , Lectinas de Plantas/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , PlântulaRESUMO
Parkia pendula (Willd.) Walp. (Fabaceae) is a neotropical species of the genus Parkia more abundantly distributed in Central to South America. From the seeds of P. pendula a glucose/mannose specific lectin (PpeL) was isolated that has been characterised and used as a biotechnological tool but until now this is the first manuscript to analyse P. pendula mRNA expression in seedlings. For this porpoise a Differential display reverse transcription polimerase chain reaction (DDRT-PCR) was used to evaluate the expression of P. pendula lectin mRNAs in non-rooted seedlings. No bands were observed in the agarose gel, indicating the absence of mRNA of PpeL seedlings. our findings confirm that lectins mRNAs are differently regulated among species even if they are grouped in the same class.
Parkia pendula (Willd.) Walp. (Fabaceae) é a espécie neotropical do gênero Parkia mais abundantemente distribuída na América Central a do Sul. Das sementes de P. pendula foi isolada uma lectina glicose/manose específica (Ppel) que foi caracterizada e usada como ferramenta biotecnológica, porém até o momento esse é o primeiro artigo a analisar a expressão do mRNA nas plântulas de P. pendula. Para esse propósito uma reação de PCR diferencial de transcriptase reversa (DDRT-PCR) foi utilizada para avaliar a expressão do mRNA da lectina de P. pendula em plântulas não enraizadas. Nenhuma banda foi observada no gel de agarose, indicando a ausência de mRNA das plântulas de PpeL. Nossos achados confirmam que os mRNAs de lectinas são regulados de forma diferentes entre as espécies, mesmo que sejam agrupadas na mesma classe.
Assuntos
Fabaceae/genética , Lectinas de Plantas/genética , RNA Mensageiro/análise , RNA de Plantas/análise , Fabaceae/química , Lectinas de Plantas/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , PlântulaRESUMO
Parkia pendula (Willd.) Walp. (Fabaceae) is a neotropical species of the genus Parkia more abundantly distributed in Central to South America. From the seeds of P. pendula a glucose/mannose specific lectin (PpeL) was isolated that has been characterised and used as a biotechnological tool but until now this is the first manuscript to analyse P. pendula mRNA expression in seedlings. For this porpoise a Differential display reverse transcription polimerase chain reaction (DDRT-PCR) was used to evaluate the expression of P. pendula lectin mRNAs in non-rooted seedlings. No bands were observed in the agarose gel, indicating the absence of mRNA of PpeL seedlings. our findings confirm that lectins mRNAs are differently regulated among species even if they are grouped in the same class.(AU)
Parkia pendula (Willd.) Walp. (Fabaceae) é a espécie neotropical do gênero Parkia mais abundantemente distribuída na América Central a do Sul. Das sementes de P. pendula foi isolada uma lectina glicose/manose específica (Ppel) que foi caracterizada e usada como ferramenta biotecnológica, porém até o momento esse é o primeiro artigo a analisar a expressão do mRNA nas plântulas de P. pendula. Para esse propósito uma reação de PCR diferencial de transcriptase reversa (DDRT-PCR) foi utilizada para avaliar a expressão do mRNA da lectina de P. pendula em plântulas não enraizadas. Nenhuma banda foi observada no gel de agarose, indicando a ausência de mRNA das plântulas de PpeL. Nossos achados confirmam que os mRNAs de lectinas são regulados de forma diferentes entre as espécies, mesmo que sejam agrupadas na mesma classe.(AU)
Assuntos
Fabaceae/genética , Lectinas de Plantas/genética , RNA Mensageiro/análise , RNA de Plantas/análise , Fabaceae/química , Lectinas de Plantas/análise , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
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 ß-sheet secondary structures are predominant in DLL (approximately 40.2% antiparallel ß-sheet, 4.6% parallel ß-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 (IC(50) = 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.
Assuntos
Dioclea/química , Lectinas de Plantas/isolamento & purificação , Lectinas de Plantas/farmacologia , Sementes/química , Vasodilatadores , Animais , Aorta/efeitos dos fármacos , Aorta/patologia , Aorta/fisiologia , Células Cultivadas , Estabilidade de Medicamentos , Eritrócitos/efeitos dos fármacos , Eritrócitos/fisiologia , Técnicas de Cultura de Órgãos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Lectinas de Plantas/análise , Lectinas de Plantas/química , Coelhos , Ratos , Ratos Wistar , Vasodilatação/efeitos dos fármacos , Vasodilatadores/análise , Vasodilatadores/química , Vasodilatadores/isolamento & purificação , Vasodilatadores/farmacologiaRESUMO
Lectins are carbohydrate-binding proteins of non-imune origin. This group of proteins is distributed widely in nature and they have been found in viruses, microorganisms, plants and animals. Lectins of plants have been isolated and characterized according to their chemical, physical-chemical, structural and biological properties. Among their biological activities, we can stress its fungicidal action. It has been previously described the effect of the lectins Dviol, DRL, ConBr and LSL obtained from the seeds of leguminous plants on the growth of yeasts isolated from vaginal secretions. In the present work the experiments were carried out in microtiter plates and the results interpreted by both methods: visual observations and a microplate reader at 530nm. The lectin concentrations varied from 0.5 to 256µg/mL, and the inoculum was established between 65-70% of trammitance. All yeast samples isolated from vaginal secretion were evaluated taxonomically, where were observed macroscopic and microscopic characteristics to each species. The LSL lectin did not demonstrate any antifungal activity to any isolate studied. The other lectins DRL, ConBr and DvioL, showed antifungal potential against yeast isolated from vaginal secretion. These findings offering offer a promising field of investigation to develop new therapeutic strategies against vaginal yeast infections, collaborating to improve women's health.
Assuntos
Humanos , Feminino , Antifúngicos/análise , Antifúngicos/isolamento & purificação , Secreções Corporais , Lectinas de Plantas/análise , Lectinas de Plantas/isolamento & purificação , Lectinas/análise , Lectinas/isolamento & purificação , Leveduras/crescimento & desenvolvimento , Leveduras/isolamento & purificação , Vaginose Bacteriana , Métodos , PacientesRESUMO
The biochemical and functional properties of 2 hard-to-cook common bean cultivars (Phaseolus vulgaris, L.) were investigated after the extrusion process. Beans of BRS pontal and BRS grafite cultivars were milled and extruded at 150 degrees C, with a compression ratio screw of 3 : 1, 5-mm die, and screw speed of 150 rpm. Extrudate flours were evaluated for water solubility (WS), water absorption index (WAI), oil absorption capacity (OAC), foaming capacity (FC), emulsifying activity (EA), antinutritional factors, and in vitro protein and starch digestibility. Results indicated that the extrusion significantly decreased antinutrients such as phytic acid, lectin, alpha-amylase, and trypsin inhibitors, reduced the emulsifying capacity and eliminated the FC in both BRS pontal and BRS grafite cultivars. In addition, the WS, WAI, and in vitro protein and starch digestibility were improved by the extrusion process. These results indicate that it is possible to produce new extruded products with good functional and biochemical properties from these common bean cultivars.
Assuntos
Quelantes/química , Digestão , Emulsificantes/química , Indústria de Processamento de Alimentos/métodos , Phaseolus/química , Sementes/química , Gorduras na Dieta/análise , Proteínas Alimentares/metabolismo , Hemaglutininas/análise , Temperatura Alta , Valor Nutritivo , Ácido Fítico/análise , Lectinas de Plantas/análise , Pressão , Solubilidade , Amido/metabolismo , Inibidores da Tripsina/análise , Água/análise , alfa-Amilases/antagonistas & inibidoresRESUMO
Plant lectins are the most studied group of carbohydrate-binding proteins. Despite the high similarity between the members of the Diocleinae subtribe (Leguminosae) group, they present differing biological activities. Canavalia boliviana lectin (Cbol) was purified using a Sephadex G-50 column and crystallized in the presence of X-Man by hanging-drop vapour diffusion at 293 K. After optimization, crystals suitable for diffraction were obtained under the condition 0.1 M HEPES pH 7.5 and 3.0 M sodium formate. The crystal belonged to the monoclinic space group C2, with unit-cell parameters a = 126.70, b = 66.64, c = 64.99 A, alpha = 90.0, beta = 120.8, gamma = 90.0 degrees . Assuming the presence of a dimer in the asymmetric unit, the solvent content was estimated to be about 46%. A complete data set was collected at 1.5 A resolution.
Assuntos
Canavalia/química , Lectinas de Plantas/química , Sementes/química , Cromatografia de Afinidade , Cristalização , Cristalografia por Raios X , Eletroforese em Gel de Poliacrilamida , Lectinas de Plantas/análiseRESUMO
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.
Assuntos
Acacia/química , Lectinas de Plantas/isolamento & purificação , Sementes/química , Sequência de Aminoácidos , Quitina/química , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia por Troca Iônica , Fabaceae , Espectrometria de Massas , Dados de Sequência Molecular , Peso Molecular , Lectinas de Plantas/análise , Lectinas de Plantas/química , Alinhamento de Sequência , Análise de Sequência de Proteína , Espectrometria de Massas em TandemRESUMO
A lectin was purified from Crotalaria paulina seeds by ion-exchange and FPLC molecular exclusion chromatography. CrpL had an apparent molecular mass of 30 kDa, as determined by SDS-PAGE under non-reducing and reducing conditions. CrpL effectively agglutinated human and cow erythrocytes, and this activity was not affected by 20 mM EDTA, showing no dependence of divalent cations. Hemagglutination was inhibited by N-acetyl-D-galactosamine, D-galactose and was also inhibited by glycoproteins, fetuin and asialofetuin. The N-terminal amino acid sequence of CrpL was identical to those of other lectins from the genus Crotalaria, and amino acid composition showed high amounts of Asx and Glx, and was rich in Gly, Ala and Ser, as also reported for lectins from other Crotalaria species. CrpL inhibited the growth of Xanthomonas axonopodis pv. phaseoli and Xanthomonas axonopodis pv. passiflorae, suggesting a role of this lectin in the defense of seeds against bacterial infections.
Assuntos
Crotalaria/química , Lectinas de Plantas/isolamento & purificação , Sementes/química , Sequência de Aminoácidos , Dados de Sequência Molecular , Lectinas de Plantas/análise , Lectinas de Plantas/químicaRESUMO
To identify molecular evidence of the common origin of maize and teosinte, a lectin from teosinte coleoptile (TCL) was purified, through affinity chromatography on a lactosyl-Sepharose column, and some of the physicochemical parameters were compared with those from the maize coleoptile lectin (CCL). TCL is a 92 kDa glycoprotein constituted mainly by aspartic, glutamic, glycine, leucine, and lysine residues; in minor proportion, methionine and cysteine were also found. The glycannic portion of the lectin, which corresponds to 10% w/w, is composed by Gal, Man, and GlcNAc. CCL is an 88.7 kDa glycoprotein that contains 12% sugars by weight; its sugar and amino acid compositions are similar to those of TCL. TCL is formed by two isoforms identified through acidic electrophoresis, whereas CCL is constituted by a single molecular form. The NH(2) termini of both TCL isoforms are blocked, but their amino acid sequences determined from tryptic peptides by matrix-assisted laser desorption ionization time-of-flight) indicated that TCL isoforms have no homology with other mono- or dicotyledonous lectins, including CCL. TCL, just as CCL, showed hemagglutinating activity toward animal erythrocytes, including human A, B, and O. Hapten inhibition assays indicated that although TCL shows broader sugar specificity than CCL, it recognizes Gal in O- and N-glycosidically linked glycans. Both lectins are equally well recognized by antibodies against TCL.