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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Caracterização de proteínas de reserva de mutantes de endosperma de milho de alta lisina / Storage proteins characterization of high-lysine maize endosperm mutants

Alberto Toro, Alejandro 17 May 2006 (has links)
A semente de milho representa uma importante fonte de proteínas para alimentação humana e de animais monogástricos. Porém, como membros da família dos cereais não apresentam proteínas com um balanço nutricional adequado, devido principalmente ao baixo conteúdo de lisina. As proteínas de reserva da semente de milho são classificadas como fração não-zeína (albumina, globulina e glutelina) e zeína. Mutantes de endosperma de milho, como o2 apresentam quantidades maiores de lisina na semente. Porém, muitos mutantes considerados "alta lisina" não foram ainda caracterizados bioquimicamente. Uma série de mutantes, opaco (o1, o2, o5, o7, o10, o11 e o13) e floury (fl1 e fl2), foram estudadas para determinar as quantidades de proteínas de reserva, o perfil electroforético das proteínas e o conteúdo de LYS na semente, endosperma e embrião. Foi observado que os mutantes apresentaram redução no conteúdo de zeína e aumentos da fração não-zeína com variações dependendo do mutante, do background genético e do tecido analisado. A análise da semente determinou aumentos principalmente da fração albumina e globulina nos mutantes, exceto para o5 com aumentos apenas da fração glutelina. No endosperma foi observado aumento principalmente de albumina em o2, o7 e o5; e globulina em fl2, o10, o11 e o13. No embrião foram registrados os níveis maiores de albumina e globulina da semente, porém a quantidade de proteínas de reserva foi similar entre os genótipos. As quantidades de lisina presentes nas frações protéicas foram sempre maiores nos mutantes, porém para o10, o11 e o13 diferenças significativas, foram observadas principalmente para LYS na fração glutelina. O perfil SDS-PAGE revelou a presença de numerosas bandas protéicas variando entre 100kDa e 10kDa, sendo que a fração não-zeína revelou maior heterogeneidade no número de bandas. Bandas protéicas de maior intensidade foram observadas nos mutantes. Análise 2D-PAGE de proteínas de reserva do endosperma de mutantes o1, o2, fl1 e fl2, revelou padrões similares de distribuição de proteínas, aumentos de intensidade de spots protéicos e a presença de spots restrita ao perfil dos mutantes. Os resultados sugerem que os mutantes opacos e floury avaliados apresentam quantidades maiores de LYS na semente quando comparados aos genótipos selvagens que lhes deram origem. A futura análise dos spots que apresentaram alterações altamente significativas permitirá uma maior compreensão dos efeitos específicos dessas mutações sobre a regulação da biossíntese das proteínas de reserva e do acúmulo de lisina no grão. / The maize seed is an important source of proteins for humans and monogastric animals. However, such as all cereals, maize storage proteins is nutritionally poor mainly due to the low content of lysine. Maize seed storage proteins can be classified as non-zeins (albumins, globulins and glutelins) and zein. Some storage proteins mutants such as the o2 mutants exhibit higher contents of lysine. However, many of these high-lysine mutants have not yet been biochemically characterized. The opaque mutants o1, o2, o5, o7, o10, o11, o13 and floury mutants fl1 and fl2 were analyzed for storage proteins contents, eletrophoretic profile and lysine content in the seeds, endosperm, and embryo. It was observed that the mutants exhibited reduction in the zein fraction and increase in the non-zein fraction which varied according to the mutant, genetic background and tissue analyzed. The whole seed analysis revealed increases mainly in albumins and globulins, with the exception of the o5 mutants which exhibited a higher increase in the glutelin fraction. In the endosperm it was observed increase in the albumin fraction in o2, o7 and o5 and in the globulin fraction in fl2, o10 and o13. Higher concentrations of albumin and globulin were observed in the embryo, but with similar concentrations of total proteins among the mutants. The lysine content was higher always higher in the storage proteins of the mutants, however, in o10, o11 and o13 significant differences for lysine content were observed mainly in the glutelin fraction. SDSPAGE analysis revealed the presence of several band varying from 10kDa to 100kDa, with a higher heterogeneity among the non-zein fraction. Bands with higher intensity have been observed in the mutants. 2D-PAGE analysis revealed that the o1, o2, fl1 and fl2 mutants exhibited similar band patterns with increases in similar spots and mutant specific bands. The results suggest that the opaque and floury mutants exhibited higher lysine content when compared to their respective wild-type counterparts. Future analysis of the protein spots that exhibited significant variations will allow a better understanding of the specific effects of each mutation on the regulation of storage protein synthesis and lysine accumulation in the seeds.
22

Fé e saber em Habermas: a reserva semântica da religião na sociedade secularizada

Schuck, Neivor 11 June 2010 (has links)
Made available in DSpace on 2016-04-25T19:21:08Z (GMT). No. of bitstreams: 1 Neivor Schuck.pdf: 500642 bytes, checksum: f2d980c4eab0384f0b24ff70dbd45de0 (MD5) Previous issue date: 2010-06-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Habermas considers religion as an important issue in contemporary semantics. We are living in a post metaphysical period and the proposal of a universal autonomy of religion does not have any support anymore. At the initial moment we work in the evolution of Habermas' thought till reaching to consider a philosophy of religion. In the second moment, we explore the possibility of philosophy of religion in Habermas. This leads one to consider the possibility of a semantic reserve of religion in a secular society. Thus, the Habermas' perspective of thinking takes into account the knowledge that is originated from religion when he opens space in the public realm for this discussion, being a epistemology of faith. This openness would make possible the philosophy of religion to think in a opaque core around the religion experience / Habermas considera a religião como uma importante reserva semântica na contemporaneidade. Por vivermos em um período pós-metafísico, a proposta de uma autonomia universal de uma religião não encontra mais suporte. No primeiro momento da dissertação, tratamos da evolução do pensamento de Habermas até chegar a uma Filosofia da Religião, algo que ocorreu lentamente. Em um segundo momento, apresentamos uma possibilidade de Filosofia da Religião em Habermas. Isso leva a postular uma possibilidade de reserva semântica contida na religião presente sociedade secular. Desse modo, a proposta de Habermas leva em conta o conhecimento proveniente da religião ao abrir espaço na esfera pública para o debate sobre a presença de reserva semântica na religião, sendo uma epistemologia da fé. Essa abertura possibilitaria à Filosofia da Religião pensar um núcleo opaco ao redor da experiência religiosa
23

Redécouverte des procédés d'opacification des verres à l'antimoine à travers l'Histoire. Etude des antimoniates de calcium.

Lahlil, Sophia 16 December 2008 (has links) (PDF)
L'objectif de ce travail de recherche est de retrouver les modes de fabrication des verres opacifiés aux antimoniates à travers l'Histoire depuis l'origine jusqu'à aujourd'hui par une approche conjointe de l'archéométrie et des sciences des matériaux. Pour ce faire, nous avons réalisé des synthèses de verres opaques en laboratoire et étudié des productions de verres opacifiés aux antimoniates de calcium allant de l'Antiquité à nos jours. En comparant les caractéristiques physico-chimiques de verres de référence synthétiques ou contemporains, dont le mode de fabrication est connu, avec celles d'échantillons de verres opaques anciens ou modernes, dont le mode de fabrication est inconnu, nous avons pu déterminer des critères permettant d'identifier les procédés d'opacification des trois productions de verre étudiées : - les verres décorés de la XVIIIème dynastie égyptienne (1570-1292 av. J.C.), - les tesselles de mosaïque romaines d'Aquilée et de Rome, datant du 1er s. av. au 4ème s. apr. J.C., - les verres filés dits « de Nevers » datant du 18ème s. apr. J.C..
24

Slow Transit Constipation : Aspects of Diagnosis and Treatment

Lundin, Erik January 2005 (has links)
<p>Oral 111-Indium-DTPA colonic scintigraphy was used to assess segmental transit in 23 patients with slow transit constipation (STC) and 13 controls. The transit time did not differ between patients and controls in the right colon, whereas the patients had a consistent delay from the transverse colon and distally (<i>P</i><0.05–0.001). Two individual patients had a delay in the right colon.</p><p>Twenty-eight patients underwent a left- (n=26) or a right (n=2) hemicolectomy for STC, after evaluation including colonic scintigraphy. Twenty-three patients (80%) were satisfied with the outcome after a median of 50 months. The median stool frequency increased from one to seven per week (<i>P</i><0.001). The number of patients with bloating, excessive straining and painful defecation decreased (<i>P</i><0.05). The laxative use decreased (<i>P</i><0.01) and faecal continence was unchanged. A blunted rectal sensation correlated to a poor outcome.</p><p>Fifty constipated patients with slow colonic transit and 28 controls were investigated with anorectal manovolumetry. Anal resting pressure was lower (<i>P</i><0.05), and squeeze pressure tended to be lower (<i>P</i>=0.09) in patients. Rectal sensation was not different between groups, although ten patients had a threshold for filling sensation above the 95<sup>th</sup> percentile of controls. The rectal compliance was increased in patients (<i>P</i><0.05–0.01).</p><p>Total and segmental colonic transit was assessed with radio-opaque marker study and scintigraphy in 35 constipated patients, and related to normal values. Twenty-seven of 31 female patients had a prolonged total transit time on marker study, and 26 on scintigraphy. Of those 31 patients, 29 had prolonged segmental transit only in one or two segments on marker study. The two methods gave a similar result, except in the descending colon (<i>P</i><0.05). However, the results varied considerably for individual patients.</p><p>In conclusion, patients with STC often benefit from a segmental colonic resection, following assessment including scintigraphy. Anorectal physiology testing may predict surgical results.</p>
25

Slow Transit Constipation : Aspects of Diagnosis and Treatment

Lundin, Erik January 2005 (has links)
Oral 111-Indium-DTPA colonic scintigraphy was used to assess segmental transit in 23 patients with slow transit constipation (STC) and 13 controls. The transit time did not differ between patients and controls in the right colon, whereas the patients had a consistent delay from the transverse colon and distally (P&lt;0.05–0.001). Two individual patients had a delay in the right colon. Twenty-eight patients underwent a left- (n=26) or a right (n=2) hemicolectomy for STC, after evaluation including colonic scintigraphy. Twenty-three patients (80%) were satisfied with the outcome after a median of 50 months. The median stool frequency increased from one to seven per week (P&lt;0.001). The number of patients with bloating, excessive straining and painful defecation decreased (P&lt;0.05). The laxative use decreased (P&lt;0.01) and faecal continence was unchanged. A blunted rectal sensation correlated to a poor outcome. Fifty constipated patients with slow colonic transit and 28 controls were investigated with anorectal manovolumetry. Anal resting pressure was lower (P&lt;0.05), and squeeze pressure tended to be lower (P=0.09) in patients. Rectal sensation was not different between groups, although ten patients had a threshold for filling sensation above the 95th percentile of controls. The rectal compliance was increased in patients (P&lt;0.05–0.01). Total and segmental colonic transit was assessed with radio-opaque marker study and scintigraphy in 35 constipated patients, and related to normal values. Twenty-seven of 31 female patients had a prolonged total transit time on marker study, and 26 on scintigraphy. Of those 31 patients, 29 had prolonged segmental transit only in one or two segments on marker study. The two methods gave a similar result, except in the descending colon (P&lt;0.05). However, the results varied considerably for individual patients. In conclusion, patients with STC often benefit from a segmental colonic resection, following assessment including scintigraphy. Anorectal physiology testing may predict surgical results.
26

Synthesis And Charaterization Of Multi-hollow Opaque Polymer Pigmets

Asmaoglu, Serdar 01 July 2012 (has links) (PDF)
In the present work, a new generation opaque polymer pigment with multihollow structure was synthesized by suspension polymerization of &ldquo / Water-in-Oil-in-Water&rdquo / (W/O/W) emulsion system. Oil phase was methyl methacrylate and ethylene glycol dimethacrylate monomer mixture at 1:1 weight ratio. The dimension and distribution of hollows inside polymer particles are dependent on the size of water droplets which are encapsulated in micelles. For Water-in-Oil (W/O) assembly, a hydrophobic surfactant and hydrophilic co-surfactant (Span 80-Tween 80) combination with a hydrophilic/lipophilic balance (HLB) value between 5-8 was used. The effects of surfactant and co-surfactant composition on the stability of the W/O emulsion and also on the size of water droplets were studied. In addition, the effect of the ultrasonication on the average size of water droplets was investigated. The hollow size distribution which may possibly give the maximum scattering efficiency was predicted by a mathematical model based on the Mie scattering. The optimum size distribution for W/O emulsion was obtained at the monomer/surfactant/water ratio of 75.5/9.4/15.1 after ultrasonication for 30 seconds at 80 W power. The W/O/W emulsion was prepared by dispersing the W/O emulsion in aqueous solution of hydrophilic Triton X-405. The influence of surfactant concentration and mechanical mixing on monomer droplets was investigated by size measurement and optical microscopy. After stabilizing with 1 %w/w polyvinylpyrrolidone (PVP) solution, the W/O/W emulsion was polymerized at 55 &deg / C for 20 h. The surface morphology of synthesized polymer pigments was analyzed by scanning electron microscopy (SEM) and the inner hollow structure was confirmed by transmission electron microscopy (TEM). The analysis indicated that multihollow opaque polymer pigments were successfully synthesized. The opacity, the L*a*b* color, and the gloss properties of polymer pigments were examined by spectrophotometer and glossmeter. The opacity values were assessed by contrast ratio measurements, and the synthesized polymer pigments provided up to 97.3 % opacity (50 %v/v solid content). In addition, the pigments exhibited low gloss values, and yielded matt films.
27

Étude des potentialités offertes par les technologies de transmission optique flexible pour les réseaux métro / coeur

Blouza, Sofiene 16 May 2013 (has links) (PDF)
L'évolution vers de nouveaux services, comme la TV à la demande, nécessitant de grosses bandes passantes remet en question les débits transportés par chaque canal optique d'un réseau WDM. Les débits des canaux ont atteint aujourd'hui les 100 Gbit/s. Cette montée en débit doit être accompagnée par de nouvelles fonctionnalités au sein des réseaux de transport optiques. Améliorer la flexibilité et assurer la transparence des réseaux optiques sont des défis très importants auxquels les opérateurs doivent faire face aujourd'hui. Un réseau optique est dit transparent, si les signaux optiques transportés ne subissent aucune conversion optoélectronique sauf au moment de leur insertion et de leur extraction dans le réseau optique. La flexibilité, quant à elle, concerne principalement les fonctions d'agrégation et de désagrégation optiques. Aujourd'hui ces fonctions d'agrégation et de désagrégation sont réalisées dans le domaine électronique, ce qui avec la montée du débit, va engendrer un coût important pour les opérateurs. Une manière d'y remédier serait de trouver une technologie adaptée à la montée du débit et offrant la possibilité de faire de l'agrégation et de la désagrégation optique des flux de trafics. Dans cette thèse nous proposons d'étudier une technique de commutation tout-optique offrant la possibilité de faire de la commutation optique intra-canal. Cette technique, baptisée multi-bande OFDM, consiste à diviser un canal WDM en plusieurs entités appelées sous-bandes. Le nombre de ces entités dépend des contraintes technologiques des équipements utilisés pour générer le canal multi-bande (les filtres optiques, les convertisseurs analogiques/numérique et numériques/analogiques). Nous comparons la technologie multi-bande OFDM par rapport à des technologies tendancielles mono-bande : le cas mono-bande opaque et mono-bande transparent. Nous démontrons que la technologie multi-bande OFDM peut être un compromis entre ces deux technologies pour les futurs réseaux de télécommunications optiques. Pour ce faire, nous calculons les performances en termes de blocage. Nous étudions l'impact de la conversion de longueurs d'onde sur les réseaux multi-bande OFDM ainsi que l'impact d'augmenter les nombres de sous-bandes sur les performances du réseau. Nous dégageons les limites technologiques de cette approche. Dans une autre partie de l'étude, nous montrons l'intérêt économique de la technologie multi-bande OFDM. Nous exposons le gain en coût des émetteurs/récepteurs obtenu grâce au déploiement de la technologie multi-bande OFDM sur un réseau cœur et un réseau métropolitain.
28

A opacidade do sujeito enunciador na construção da escrita.

Sampaio, Maria das Graças de Castro January 2007 (has links)
Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2013-05-13T16:07:11Z No. of bitstreams: 1 Maria Sampaio.pdf: 371162 bytes, checksum: eb109fcc7138e5eb0e4c3410f3fec223 (MD5) / Approved for entry into archive by Alda Lima da Silva(sivalda@ufba.br) on 2013-06-04T20:50:22Z (GMT) No. of bitstreams: 1 Maria Sampaio.pdf: 371162 bytes, checksum: eb109fcc7138e5eb0e4c3410f3fec223 (MD5) / Made available in DSpace on 2013-06-04T20:50:22Z (GMT). No. of bitstreams: 1 Maria Sampaio.pdf: 371162 bytes, checksum: eb109fcc7138e5eb0e4c3410f3fec223 (MD5) Previous issue date: 2007 / O desempenho de estudantes do Ensino Médio da Rede Particular de Ensino de Salvador, no que se refere à produção escrita, tem decaído em qualidade. As evidências disso são notórias. A resposta inadequada ao ensino da escrita, mais especificamente de um tipo textual que percorre as três séries do Ensino Médio, tem sido atribuída ao descompromisso e capacidade deficitária desses jovens. O interesse pela questão repercute nesta pesquisa, que reúne três caminhos teóricos na busca do entendimento desse fenômeno: a Análise do Discurso de linha francesa quanto à dificuldade do sujeito enunciador de produzir textos que tenham a transparência necessária ao entendimento do interlocutor, na educação que se pretende dialógica; a função da escola no que diz respeito à formação de estudantes de consciências críticas (PAULO FREIRE) bem como de sujeitos interactantes e, por fim, a integração do trabalho didático de produção de textos na teoria de VYGOTSKY de que a aprendizagem promove o desenvolvimento mental, não o inverso, e também de que a aprendizagem da escrita acrescenta à vida novos e complexos ciclos de desenvolvimento de processos mentais, equivalentes em importância aos da aquisição da linguagem. Após a análise desses elementos como responsáveis pela tessitura do trabalho pedagógico de ensino da produção escrita, são analisados 18 textos de alunos da 1ª série do Ensino Médio, apresentados como resposta a dois diferentes temas. Nesses textos, usando o paradigma indiciário de GINZBURG (2003), buscam-se as configurações singulares e as regularidades que se ocultam sob a opacidade nesses espaços de dissenções (FOUCAULT, 2004). Chega-se, assim, à suposição, ainda que preliminar, de que esses enunciadores de discurso opaco são frutos da sociedade, da escola e da visão equivocada de professores quanto ao desenvolvimento cognitivo de estudantes desse seriado. / Salvador
29

sanirizaçãp e refrigeração de ovos de codornas comercias contaminados experemente por Salmonella Typhimurium / sanitization and cooling of quail eggs artificially contaminated with Salmonella Typhimurium

LACERDA, Maria Juliana Ribeiro 26 February 2011 (has links)
Made available in DSpace on 2014-07-29T15:07:35Z (GMT). No. of bitstreams: 1 Maria Juliana Lacerda Dissertacao.pdf: 580972 bytes, checksum: afedaefa404680a1d528d495b7558c61 (MD5) Previous issue date: 2011-02-26 / The objective of this study was to verify the physical, chemical and microbiological quality of Japanese quail eggs artificially contaminated with Salmonella Typhimurium, sanitized and stored at different temperatures (between 5 and 25 ºC) for 27 days. We used 768 eggs with opaque shells (Experiment 1) and bright shells (Experiment 2) with typical pigments of the species and average weight of 11 g. The experimental design was completely randomized in a 2x2x2 factorial arrangement (contamination x sanitation x cooling) with six replications, with one egg per experimental unit. The eggs were contaminated by handling with 1.5 x 105 colony forming unit (CFU) of Salmonella Typhimurium / mL and according to the treatments, sanitized with 5ppm Cl a solution, and stored at 5 or 25 ° C. The physical (egg weight, specific gravity, shell thickness, yolk, albumen and shell ratio, Haugh unit, yolk albumen index), chemical (pH of yolk and albumen) and bacteriological (bacterial count in eggshell and egg content) qualities were analyzed. Results of Experiment 1 showed a inear regression of sorage time (P <0.05) of storage time (up to 27 days) worsening the variables of egg weight, albumen and yolk index and albumen ratio. A quadratic effect (p <0.05) of storage time worsening the pH of albumen and Haugh units. There was an interaction for the yolk pH variable between sanitation and refrigeration (p <0.05) after 27 days, while those for non refrigerated eggs the best result was for sanitized eggs, showing the importance of sanitization. In Experiment 2 (eggs with bright shells) there was a linear effect (P <0.05) of storage time (27 days), worsening the variables of egg weight, albumen ratio and Haugh units and quadratic effects (p <0.05) worsening albumen index and pH. These results indicate that eggs with opaque or bright, had a poorer quality with increasing internal storage time, especially at 25 ° C. Quail eggs with opaque or bright shell, stored up to 27 days, should be sanitized (5 ppm of chlorine) and cooled to 5 ° C during storage to maintain physical and chemical qualities, regardless of bacterial contamination. The sanitization (5 ppm Cl) and cooling (5 º C) are effective in reducing the growth of Salmonella in experimentally infected quail eggs. / Objetivou-se com este estudo verificar a qualidade física, química e microbiológica de ovos de codornas japonesas contaminados artificialmente com Salmonella Typhimurium, sanitizados e armazenados a diferentes temperaturas (5 e 25 ºC) durante 27 dias. Foram utilizados 768 ovos com cascas opacas (Experimento 1) e brilhantes (Experimento 2) com pigmentos típicos da espécie e com peso médio de 11 g. O delineamento empregado foi inteiramente casualisados com esquema fatorial 2x2x2 (contaminação x sanitização x refrigeração) com seis repetições, sendo um ovo a unidade experimental. Os ovos foram contaminados pelo manuseio com 1,5 x 105 unidade formadoras de colônias (UFCs) de Salmonella Typhimurium/mL e de acordo com os tratamentos foram sanitizados com solução com 5ppm de Cl e armazenados a 5 ou 25 ºC. Foi analisada a qualidade física (peso do ovo, gravidade específica, espessura de casca, percentagem de gema, albume e casca, unidade Haugh, índices de gema e albume), química (pH de gema e albume) e bacteriológica (contagem de bactérias na casca e no conteúdo do ovo). Os resultados de peso do ovo, uH, índice de gema e de albume e pH de gema e de albume, quando contaminados experimentalmente com Salmonella Typhimurium prejudicou a qualidade física do ovo a partir de 18 dias de armazenamento. Com relação a qualidade bacteriológica do ovo, a sanitização com 5 ppm de Cl pode ser uma alternativa simples e de baixo custo para reduzir a possibilidade de contaminação por Salmonella em ovos de codornas. Pode-se afirmar, que o tempo de estocagem dos ovos e a temperatura de armazenamento influenciaram a qualidade interna dos ovos de codornas em todas as variáveis estudadas. Esses resultados indicam que ovos com cascas opacas ou brilhantes, apresentaram pior qualidade interna com o aumento do tempo de armazenamento, principalmente na temperatura de 25 ºC. Ovos de codornas com casca opaca ou brilhante, armazenados até 27 dias, devem ser sanitizados ( 5 ppm de cloro) e refrigerados a 5 ºC durante a estocagem para manter a qualidade física e química, independentemente da contaminação por bactérias. A sanitização (5 ppm de Cl) e a refrigeração (temperatura de 5 ºC) são eficientes na redução do crescimento da Salmonella em ovos de codornas contaminados experimentalmente.
30

Caracterização de proteínas de reserva de mutantes de endosperma de milho de alta lisina / Storage proteins characterization of high-lysine maize endosperm mutants

Alejandro Alberto Toro 17 May 2006 (has links)
A semente de milho representa uma importante fonte de proteínas para alimentação humana e de animais monogástricos. Porém, como membros da família dos cereais não apresentam proteínas com um balanço nutricional adequado, devido principalmente ao baixo conteúdo de lisina. As proteínas de reserva da semente de milho são classificadas como fração não-zeína (albumina, globulina e glutelina) e zeína. Mutantes de endosperma de milho, como o2 apresentam quantidades maiores de lisina na semente. Porém, muitos mutantes considerados “alta lisina” não foram ainda caracterizados bioquimicamente. Uma série de mutantes, opaco (o1, o2, o5, o7, o10, o11 e o13) e floury (fl1 e fl2), foram estudadas para determinar as quantidades de proteínas de reserva, o perfil electroforético das proteínas e o conteúdo de LYS na semente, endosperma e embrião. Foi observado que os mutantes apresentaram redução no conteúdo de zeína e aumentos da fração não-zeína com variações dependendo do mutante, do background genético e do tecido analisado. A análise da semente determinou aumentos principalmente da fração albumina e globulina nos mutantes, exceto para o5 com aumentos apenas da fração glutelina. No endosperma foi observado aumento principalmente de albumina em o2, o7 e o5; e globulina em fl2, o10, o11 e o13. No embrião foram registrados os níveis maiores de albumina e globulina da semente, porém a quantidade de proteínas de reserva foi similar entre os genótipos. As quantidades de lisina presentes nas frações protéicas foram sempre maiores nos mutantes, porém para o10, o11 e o13 diferenças significativas, foram observadas principalmente para LYS na fração glutelina. O perfil SDS-PAGE revelou a presença de numerosas bandas protéicas variando entre 100kDa e 10kDa, sendo que a fração não-zeína revelou maior heterogeneidade no número de bandas. Bandas protéicas de maior intensidade foram observadas nos mutantes. Análise 2D-PAGE de proteínas de reserva do endosperma de mutantes o1, o2, fl1 e fl2, revelou padrões similares de distribuição de proteínas, aumentos de intensidade de spots protéicos e a presença de spots restrita ao perfil dos mutantes. Os resultados sugerem que os mutantes opacos e floury avaliados apresentam quantidades maiores de LYS na semente quando comparados aos genótipos selvagens que lhes deram origem. A futura análise dos spots que apresentaram alterações altamente significativas permitirá uma maior compreensão dos efeitos específicos dessas mutações sobre a regulação da biossíntese das proteínas de reserva e do acúmulo de lisina no grão. / The maize seed is an important source of proteins for humans and monogastric animals. However, such as all cereals, maize storage proteins is nutritionally poor mainly due to the low content of lysine. Maize seed storage proteins can be classified as non-zeins (albumins, globulins and glutelins) and zein. Some storage proteins mutants such as the o2 mutants exhibit higher contents of lysine. However, many of these high-lysine mutants have not yet been biochemically characterized. The opaque mutants o1, o2, o5, o7, o10, o11, o13 and floury mutants fl1 and fl2 were analyzed for storage proteins contents, eletrophoretic profile and lysine content in the seeds, endosperm, and embryo. It was observed that the mutants exhibited reduction in the zein fraction and increase in the non-zein fraction which varied according to the mutant, genetic background and tissue analyzed. The whole seed analysis revealed increases mainly in albumins and globulins, with the exception of the o5 mutants which exhibited a higher increase in the glutelin fraction. In the endosperm it was observed increase in the albumin fraction in o2, o7 and o5 and in the globulin fraction in fl2, o10 and o13. Higher concentrations of albumin and globulin were observed in the embryo, but with similar concentrations of total proteins among the mutants. The lysine content was higher always higher in the storage proteins of the mutants, however, in o10, o11 and o13 significant differences for lysine content were observed mainly in the glutelin fraction. SDSPAGE analysis revealed the presence of several band varying from 10kDa to 100kDa, with a higher heterogeneity among the non-zein fraction. Bands with higher intensity have been observed in the mutants. 2D-PAGE analysis revealed that the o1, o2, fl1 and fl2 mutants exhibited similar band patterns with increases in similar spots and mutant specific bands. The results suggest that the opaque and floury mutants exhibited higher lysine content when compared to their respective wild-type counterparts. Future analysis of the protein spots that exhibited significant variations will allow a better understanding of the specific effects of each mutation on the regulation of storage protein synthesis and lysine accumulation in the seeds.

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