β2-microglobulin (β2m) exists free of the major histocompatibility complex class I (MHC I) receptor in many bodily fluids. The amount of protein present in these fluids has been found to be a useful prognostic marker for various diseases but outside of its practical value not much is known about this form of β2m. In fish, soluble β2m has not been studied at all. Another unknown in fish is the effects that plants lectins might have on naturally carnivorous species in aquaculture. These plant proteins which bind to specific sugar groups found on cells have been shown to have a multitude of gastrointestinal and immune effects in mammals and can be found in the plant products being fed to carnivorous, cultured fish making them possible toxicants. The two studies of this thesis set out to pioneer knowledge on these subjects using rainbow trout as a model. The first investigation inspected the various body fluids of these fish for their free β2m content. Soluble β2m was found to be present in the plasma, the seminal fluid, ovarian fluid, and the mucus of the skin and intestines. This distribution shows that β2m could indeed make a good biomarker, not only for disease but also for pheromone release and alludes to some possible functions of soluble β2m while opening the way for future research on this form of the protein. The second study looked at the effects of lectins on the gut of rainbow trout by treating RTgutGC, an intestinal epithelial cell line derived from trout, with plant lectins from wheat (WGA) and soybean (SBA), among others. This study found WGA to be a potent inducer of morphological and cytotoxic effects in these cells while other lectins and plant factors were not. WGA was also observed to effect the expression of β2m and the α-chain of the MHC I receptor. This work suggests WGA ingested by trout through the wheat in their diet might be causing them harm and should be studied further. It is also interesting that both studies related β2m to the intestines of trout. This could allow soluble β2m to serves as a marker of WGA’s effect or for WGA to aid in the study of free β2m.

Interactions between carbohydrates and proteins are increasingly being recognized as crucial in many biological processes, such as cellular adhesion and communication. In order to investigate the interactions of carbohydrates and proteins, the development of efficient analytic technologies, as well as novel strategies for the synthesis of carbohydrates, have to be explored. To date, several methods have been exploited to analyze interactions of carbohydrates and proteins, for example, biosensors, nuclear magnetic resonance (NMR); enzyme-linked immunosorbent assays (ELISA), X-ray crystallography and array technologies. This thesis describes the development of novel strategies for the synthesis of carbohydrates, as well as new efficient strategies to Quartz Crystal Microbalance- (QCM-) biosensors and carbohydrate microarrays technologies. These methodologies have been used to probe carbohydrate-lectin-interactions for a range of plant and animal lectins. / QC 20100915

Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 145-158). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 145-158). Also available on the Internet.

Thesis (Master of Science) -- University of Texas Southwestern Medical Center at Dallas, 2006. / Embargoed. Vita. Bibliography: 147-160.

Thesis (Ph.D.)--Uniformed Services University of the Health Sciences, 2006 / Typescript (photocopy)

This study has assessed the effects of pulse type and processing (soaking and cooking) on antinutritional factors (α-amylase inhibitor, trypsin inhibitor, chymotrypsin inhibitor, lectins, phytic acid and oxalates) in a wide range of Canadian pulses, using soybean as a control. The contents of these antinutrients in Canadian pulses varied widely, but the levels were generally lower than those found in soybean. Analysis of variance indicated that both pulse type and processing had significant effects (P < 0.0001) on the investigated seeds. Soaking markedly decreased the contents of α-amylase inhibitor, trypsin inhibitor, chymotrypsin inhibitor, lectins and oxalates, but had no impact on phytic acid. Cooking of presoaked seeds appeared to be more effective; all proteinaceous antinutrients (α-amylase inhibitor, trypsin inhibitor, chymotrypsin inhibitor and lectins) were decreased by 80 – 100%, and significant reductions in phytic acid content (11 – 39%) were observed for all pulses, except common beans and soybean. / February 2016

Made available in DSpace on 2015-05-14T12:59:23Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1655231 bytes, checksum: 254c31110cb1231f1b493b372fc7eb41 (MD5) Previous issue date: 2009-06-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Lectins constitute a class of glycoproteins which are capable of binding carbohydrates selectively and reversibly, distinguishing small structural differences in complex oligosaccharides. Some studies have shown that binding of lectins to carbohydrate surface of normal and tumor cells leads to various biological effects such as, cell proliferation in normal lymphocytes and apoptosis in tumor cells. This study investigated the assessment of cytotoxic lectins of legumes Canavalia ensiformis (ConA), Canavalia brasiliensis (Conbr) and Cratylia floribunda (CFL) in normal, mouse peritoneal macrophage, and tumor cells. Initially the cytotoxic activity of the lectins was evaluated by reduction of tetrazolium (MTT) salt assay and measured the content of nucleic acids (CAN). ConA, Conbr and CFL not decreased the viability of peritoneal macrophages, but showed to be cytotoxic for J774, MCF-7, Molt-4 and HL-60 lineages. The MTT assay was more sensitive to the effects of lectins on cell viability and ConA was the most cytotoxic, followed by Conbr and CFL. The IC50 values ranged from around 10, 20 and 45μg/mL at ConA, Conbr and CFL respectively. The genotoxic potential of lectins was also evaluated using the comet assay, showing that proteins had a high rate of lesions in DNA from MCF-7, Molt-4 and H-60 cells, reaching a damage frequency exceeding 70% in concentration of 50 μg/mL for all lectins. The lectins caused morphological changes as assessed by differential staining with ethidium bromide and acridine orange, characteristic of apoptosis, and necrosis can be observed in higher lectin concentrations in tumor cell lines. In tests that evaluated the apoptosis, ConA, Conbr and CFL caused internucleossomal fragmentation, loss of membrane integrity which is characteristic of late apoptosis or necrosis, and mitochondrial depolarization. It was concluded that ConA, Conbr and CFL exhibited cytotoxicity to tumor cells causing cell death by apoptosis, therefore these proteins can be considered as a class of molecules with antitumor potential. / Lectinas constituem uma classe de glicoproteínas que ligam-se reversivelmente e seletivamente à carboidratos, sendo capazes de distinguir pequenas diferenças estruturais em oligossacarídeos complexos. Estudos têm mostrado que a ligação de lectinas a carboidratos de superfície de células normais e tumorais provoca vários efeitos biológicos, tais como, proliferação celular em linfócitos normais e apoptose em células tumorais. Neste trabalho, foi investigado a citotoxicidade das lectinas de plantas Canavalia ensiformis (ConA), Canavalia brasiliensis (Conbr) e Cratylia floribunda (CFL), sobre linhagens de células normais e tumorais. Inicialmente, a atividade citotóxica das lectinas foi avaliada pelos ensaios de redução do sal de tetrazólio (MTT) e medida do conteúdo de ácidos nucléicos (CAN). As lectinas ConA, Conbr e CFL não diminuíram a viabilidade de células normais (macrófagos peritoneais), no entanto, mostraram-se citotóxicas para as linhagens tumorais J774, MCF-7, MOLT-4 e HL-60. O ensaio de MTT foi o mais sensível aos efeitos das lectinas sobre a viabilidade celular do que o ensaio de CAN, sendo ConA a lectina mais citotóxica, seguida de Conbr e CFL. Os valores de CI50 variaram em torno de 10, 20 e 45μg/mL, para ConA, Conbr e CFL repectivamente. O potencial genotóxico das lectinas também foi avaliado usando o teste do cometa, mostrando que essas proteínas produziram alto índice de lesões do DNA nas células MCF-7, MOLT-4 e HL-60, atingindo uma freqüência de danos superior a 70% na concentração de 50μg/mL para todas as lectinas. Nessas mesmas linhagens tumorais, as lectinas também causaram alterações morfológicas, avaliadas por coloração diferencial com brometo de etídeo e laranja de acridina, características de apoptose, sendo possível observar necrose nas concentrações mais elevadas. Nos ensaios que avaliaram apoptose, as lectinas ConA, Conbr e CFL causaram fragmentação internucleossomal e perda da integridade de membrana, nas maiores concentrações testadas e despolarização mitocondrial. Concluiu-se que as lectinas ConA, Conbr e CFL são citotóxicas para as células tumorais causando morte celular por apoptose, podendo ser consideradas como uma classe de moléculas com elevado potencial antitumoral.

Submitted by Raniere Barreto (raniere.barros@ufvjm.edu.br) on 2018-05-10T17:58:30Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) alcides_alves_freitas.pdf: 1707403 bytes, checksum: f9233629066db73fd877b2885aa875bd (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-05-14T14:47:32Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) alcides_alves_freitas.pdf: 1707403 bytes, checksum: f9233629066db73fd877b2885aa875bd (MD5) / Made available in DSpace on 2018-05-14T14:47:32Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) alcides_alves_freitas.pdf: 1707403 bytes, checksum: f9233629066db73fd877b2885aa875bd (MD5) Previous issue date: 2017 / O boldo da terra (Plectranthus barbatus) ? popularmente utilizado para o tratamento de dist?rbios gastrintestinais e para doen?as hep?ticas. Devido ? exist?ncia de um grande n?mero de esp?cies dispon?veis para pesquisa e estudos farmacol?gicos, o estudo dessa planta torna-se importante para o conhecimento t?cnico-cient?fico, especialmente com a finalidade do desenvolvimento de novos f?rmacos. Com isto, o objetivo desse trabalho foi detectar prote?nas ativas de Plectranthus barbatus (boldo da terra) e avaliar a atividade biol?gica em c?lulas A549 e RAW264.7. As amostras dos procedimentos de extra??o das folhas e caule do P. barbatus foram submetidas ? quantifica??o de prote?na. Foi detectado em gel de poliacrilamida SDS-PAGE 12% prote?nas com peso molecular em torno de 30kDa e 94kDa o que ? descrito na literatura como lectinas e lipoxigenases. Os extratos foram caracterizados por cromatografia l?quida de alta efici?ncia com picos aparentes em 16 e 27 minutos. N?o foi detectada atividade de inibi??o da tripsina. Os resultados dos testes biol?gicos em cultura de c?lulas demonstraram que o extrato purificado de inibidores de protease n?o alterou a viabilidade celular de ambas as linhagens, no entanto, foi capaz de inibir a produ??o de ?xido n?trico na concentra??o de 10 ?g/ml para folha e caule e 100 ?g/ml para folha. Este trabalho demonstra pela primeira vez a extra??o de prote?nas em folhas e caule de Plectranthus barbatus e a atividade dessa mol?cula em cultura celular. Esse extrato n?o alterou a viabilidade celular de ambas as linhagens celulares, podendo ser caracterizados como n?o citot?xico nas concentra??es testadas. Conclui-se, portanto, que embora as folhas, caules e flores do Plectranthus barbatus seja utilizado amplamente pela popula??o esse trabalho demonstrou a detec??o de lectina e lipoxigenase at? agora desconhecidos nessa esp?cie em estudo. / Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Tecnologia, Sa?de e Sociedade, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / The boldo da terra (Plectranthus barbatus) is popularly used for the treatment of gastrointestinal disorders and for liver diseases. Due to the existence of a large number of species available for research and pharmacological studies, the study of this plant becomes important for technical-scientific knowledge, especially for the purpose of developing new drugs. With this, the objective of this work was to detect active proteins of Plectranthus barbatus and to evaluate the biological activity in cells A549 and RAW264.7. Samples of P. barbatus leaf and stem extraction procedures were submitted to protein quantification. SDS-PAGE was detected in 12% proteins with molecular weight around 30kDa and 94kDa which is described in the literature as lectins and lipoxygenases. The extracts were characterized by high performance liquid chromatography with apparent peaks at 16 and 27 minutes. No trypsin inhibition activity was detected. The results of the biological tests in cell culture demonstrated that the purified protease inhibitor extract did not alter the cell viability of both strains, however, it was able to inhibit the production of 10 ?g / ml nitric oxide to leaf and And 100 ?g / ml for leaf. This work demonstrates for the first time the extraction of proteins in leaves and stem of Plectranthus barbatus and the activity of this molecule in cell culture. This extract did not alter the cellular viability of both cell lines and could be characterized as non-cytotoxic at the concentrations tested. It was concluded, therefore, that although the leaves, stems and flowers of Plectranthus barbatus were used extensively by the population, this work demonstrated the detection of lectin and lipoxygenase hitherto unknown in this species under study.

LANDIM, Patrícia Gadelha de Castro. Xiloglucanas e galactomananas de leguminosas: interação com lectinas D-galactose-ligantes. 2007. 100 f. Dissertação (Mestrado em Bioquímica) - Universidade Federal do Ceará, Fortaleza-CE, 2007. / Submitted by Eric Santiago (erichhcl@gmail.com) on 2016-06-27T12:54:01Z No. of bitstreams: 1 2007_dis_pgclandim.pdf: 1768165 bytes, checksum: f8cb9e6a16de4f08d984b33f047c8bd5 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-08-02T20:08:26Z (GMT) No. of bitstreams: 1 2007_dis_pgclandim.pdf: 1768165 bytes, checksum: f8cb9e6a16de4f08d984b33f047c8bd5 (MD5) / Made available in DSpace on 2016-08-02T20:08:26Z (GMT). No. of bitstreams: 1 2007_dis_pgclandim.pdf: 1768165 bytes, checksum: f8cb9e6a16de4f08d984b33f047c8bd5 (MD5) Previous issue date: 2007 / Polysaccharides are found in large quantity in seeds and they represent the main compounds of cell wall or reservoir. Among reservoir compounds, it included cotyledonary xyloglucans and endospermic galactomannans. The xyloglucans are made of a main chain of β-D-(1→4)-glucan with α-(1→6) ramifications of D-xylopyranoside or β-D-galactopyranoside-(1→2)-D-xylopyranoside residues. Endospermic galactomannans are polimeric chains of β-D-mannopyranosil (1→4) and replaceabled in O-6 for units of α-D-galactopyranosil. The aim of this work is investigate the interaction of xyloglucans and galactomannans with galactose bounding lectins and show the possibility of the usage of these polysaccharides as cheap and useful chromatographic matrices for isolation and determination of anomeric specificity of galactose bounding lectins. The interactions of lectins from seeds of Artocarpus integrifolia (frutalin), Artocarpus incisa (jacalin), Ricinus communis (ricin) e Arachis hypogaea (PNA) were performed with coluns of xyloglucans of seeds from Copaifera langsdorffii, Mucuna sloanei and Hymenaea courbaril (MC, MMu, MJ, respectively) and galactomannans from Mimosa scabrella, Stryphnodendron barbatiman, Adenanthera pavonina and Dimorphandra mollis (MM, MS, MA; MD, respectively). The galactomannans showed the best colun interaction capacity for the jacalin (MA – 0,92 mg ; MM – 1,48 mg ; MD –0,88 mg ; MS – 0,83 mg) and frutalin (MA – 0,99 mg ; MM – 1,09 mg ; MD - 0,94 mg ; MS - 0,85 mg) lectins. Remarkably the M. scabrella galactomannan showed the best colun interaction among all lectins analysed. On the other hand, ricin was better hold in coluns made of xyloglucan (MMu – 2,17 mg ;MJ – 1,30 mg; MC – 2,83 mg). For PNA lectin, differences were detected in colun interaction capacity. The best colun interaction was with the M. sloanei matrix (0,12 mg) for PNA lectin. All coluns were fill with sample extract of flour from seeds and hemagglutination assays was performed with PI and PII. In these assays, hemagglutination activity was detected in both PI and PII from the coluns. For ricin, toxic activity was made and it was detected for all obtained chromatographic samples. With SDS-PAGE it was possible confirmed the purification of the studied lectins. The bands in polyacrilamid gel were the same for the lectins purified. In conclusion, it can be suggested the usage of xyloglucans and galactomannans for isolation, purification and determination of anomeric specificity of galactose-bounding lectins. / Polissacarídeos ocorrem em grandes quantidades nas sementes como componentes da parede celular ou como reserva. Dentre estes últimos, incluem-se as xiloglucanas cotiledonárias e as galactomananas endospérmicas. As xiloglucanas apresentam uma cadeia principal de β-D-(1→4)-glucana ramificada com ligações α-(1→6) por resíduos D-xilopiranosídeos ou β-D-galactopiranosídeo-(1→2)-D-xilopiranosídeos, enquanto as galactomananas endospérmicas consistem em cadeias poliméricas de resíduos β-D-manopiranosil (1→4) ligados, substituídos em O-6 por unidades de α-D-galactopiranosil. O objetivo deste trabalho foi analisar a interação de xiloglucanas e galactomananas com lectinas galactose-ligantes e, assim, sugerir o uso de tais polissacarídeos como alternativa barata e eficaz na preparação de matrizes cromatográficas para o isolamento e determinação da especificidade anomérica de novas lectinas. Dessa forma, as interações das lectinas das sementes de Artocarpus integrifolia (frutalina), Artocarpus incisa (jacalina), Ricinus communis (ricina) e Arachis hypogaea (PNA) com matrizes de xiloglucanas de sementes de Copaifera langsdorffii, Mucuna sloanei e Hymenaea courbaril (MC, MMu, MJ, respectivamente) e de galactomananas de Mimosa scabrella, Stryphnodendron barbatiman, Adenanthera pavonina e Dimorphandra mollis (MM, MS, MA; MD, respectivamente) foram analisadas. As galactomananas apresentaram melhor capacidade de retenção da jacalina (MA – 0,92 mg ; MM – 1,48 mg ; MD –0,88 mg ; MS – 0,83 mg) e da frutalina (MA – 0,99 mg ; MM – 1,09 mg ; MD – 0,94 mg ; MS – 0,85 mg), lectinas que possuem especificidade por α-D-galactose. Vale destacar que a galactomanana de M. scabrella apresentou melhor capacidade de retenção da lectinas testadas. Por outro lado a ricina, capaz de ligar-se aos dois anômeros, mas que se liga preferencialmente ao anômero β, teve maior massa retida nas colunas de xiloglucana (MMu – 2,17 mg ;MJ – 1,30 mg; MC – 2,83 mg). Houve diferença nos perfis de retenção da PNA, que também se liga aos anômeros α e β da galactose, sendo que a melhor retenção foi na coluna contendo matriz de M. sloanei (0,12 mg). As colunas foram todas saturadas com extrato bruto a partir das farinhas das sementes, para que se utilizasse a capacidade máxima de retenção de cada matriz. Atividade hemaglutinante foi detectada em ambos os picos PI e PII. Para a ricina, atividade tóxica foi realizada e detectada para todos os PII obtidos. Por meio de SDS-PAGE, a pureza de cada uma das lectinas foi confirmada. Diante dos resultados expostos, pode-se sugerir o uso de xiloglucanas e galactomananas para o isolamento, purificação e determinação da especificidade anomérica de lectinas galactose-ligantes.