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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
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 17/05/2006 PT
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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...

Caracterização de proteínas de reserva, perfil de aminoácidos e enzimas envolvidas no metabolismo de lisina em cevada (Hordeum vulgare L.) geneticamente modificada; Characterization of storage proteins, amino acid profile and enzymes involved in lysine metabolism in genetic modified barley (Hordeum vulgare L.)

Schmidt, Daiana
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 16/05/2011 PT
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Os cereais representam importantes fontes de proteína para alimentação humana e animal. Entretanto, são caracterizados pela baixa qualidade nutricional de suas proteínas devido à composição desbalanceada de aminoácidos, causada pelo excesso dos aminoácidos prolina e glutamina e deficiência de lisina, treonina e triptofano. As proteínas de reserva prolaminas constituem 50% do conteúdo total de proteínas no endosperma e são as principais responsáveis por tais características nos cereais. As informações sobre o metabolismo de lisina e o acúmulo de proteínas de reserva no endosperma vêm sendo utilizadas para desenvolver e aplicar estratégias em programas de melhoramento de plantas que visam suprir a deficiência de lisina encontrada nos cereais. Lange e colaboradores (2007) relataram a produção de linhagens transgênicas de cevada com padrão de proteínas de reserva alterado e que apresentaram incremento no teor de lisina e outros aminoácidos essenciais. O presente trabalho teve como objetivo identificar os mecanismos responsáveis pelas alterações observadas. Para tanto, avaliou-se a atividade das enzimas envolvidas na síntese e degradação de lisina, além da caracterização das proteínas de reserva e sua composição de aminoácidos. Observou-se redução na fração protéica das prolaminas (5...

Caracterização das enzimas chaves para o controle do metabolismo de lisina em milho (Zea mays L.) geneticamente modificado; Key enzymes characterization to the control of lysine metabolism in genetic modified corn (Zea mays L.)

Rizzi, Vanessa
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 24/05/2013 PT
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A lisina é um dos aminoácidos essenciais e um dos fatores limitantes ao uso de cereais como o milho na alimentação, pois, sem suplementação, não permite a obtenção de uma dieta balanceada. A fim de melhorar a qualidade nutricional dos cereais, várias tentativas têm sido realizadas baseadas em resultados obtidos sobre as rotas de metabolismo da lisina em plantas e o acúmulo de proteínas de reserva no endosperma. Ambrozevicius (2010) com o objetivo de produzir plantas de milho transgênicas com alto teor de lisina utilizou a estratégia de expressão de proteínas de reserva de outras espécies vegetais ricas em lisina, ou seja, através da expressão de uma proteína heteróloga: a zeolina. O presente trabalho teve como objetivo estudar os 6 eventos transformados expressando a zeolina na geração F3, caracterizando as proteínas de reserva, o perfil de aminoácidos e as enzimas envolvidas no metabolismo de lisina em milho geneticamente modificado, para compreender quais as possíveis alterações bioquímicas podem ter sido geradas pela transformação, e que podem ter levado ao incremento dos aminoácidos essenciais neste material transgênico. O perfil de proteínas de reserva dos eventos transformados exibiu redução na proporção das zeínas II e glutelinas em relação ao controle HiII...

Lysine supplementation in late gestation of gilts: effects on piglet birth weight, and gestational and lactationanl performance; Suplementação de lisina no terço final da gestação de leitoas: efeitos no peso ao nascimento de leitões e no desempenho gestacional e lactacional

Magnabosco, Diogo; Bierhals, Thomas; Ribeiro, Renato Rosa; Cemin, Henrique Scher; Faccin, Jamil Elias Ghiggi; Bernardi, Mari Lourdes; Wentz, Ivo; Bortolozzo, Fernando Pandolfo
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
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As exigências de lisina durante a gestação, para o ganho de reservas corporais maternas e peso ao nascer dos leitões, não estão bem estabelecidas nos genótipos contemporâneos prolífi cos. Este estudo objetivou avaliar o efeito da suplementação de lisina no terço fi nal da gestação, sobre o peso ao nascer dos leitões e o desempenho gestacional e lactacional de leitoas. Leitoas prenhes foram uniformemente distribuídas em dois grupos que receberam, dos 85 aos 110 dias de gestação, diferentes níveis de lisina na dieta: Grupo Controle – 28g lisina/dia (n=136), e Grupo Lisina – 35g lisina/dia (n=141). Não houve efeito (P>0,10) da suplementação de lisina no ganho de peso e espessura de toucinho (ET) das fêmeas e no peso dos leitões ao nascer. Leitoas suplementadas com lisina tenderam a ter menor percentagem de natimortos (P=0,077), menor variação de peso dentro da leitegada (P= 0,094) e menor percentagem de leitões pesando menos que 1100g (P=0,082), em comparação ao grupo controle. Durante a lactação, o desempenho das fêmeas e das leitegadas foi avaliado em um subgrupo de fêmeas (n=26/grupo). Não houve diferença entre os grupos Controle e Lisina (P>0,10) no consumo voluntário de ração, perdas de reservas corporais (peso e ET)...

Dietary digestible lysine requirement and essential amino acid to lysine ratio for pacu Piaractus mesopotamicus

Abimorad, Eduardo Gianini; Favero, G. C.; Squassoni, G. H.; Carneiro, D.
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 370-377
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 04/06060-6; To determine the digestible lysine requirement for pacu juveniles, a dose-response feeding trial was carried out. The fish (8.66 +/- 1.13 g) were fed six diets containing the digestible lysine levels: 6.8, 9.1, 11.4, 13.2, 16.1 and 19.6 g kg-1 dry diet. The gradual increase of dietary digestible lysine levels from 6.8 to 13.2 g kg-1 did not influence the average values of the parameters evaluated (P > 0.05). The increase of dietary digestible lysine level to 16.1 g kg-1 significantly improved weight gain (WG), specific growth rate (SGR), protein productive value (PPV), protein efficiency rate (PER), and apparent feed conversion rate (FCR), but was not different from fish fed diets containing 19.6 g kg-1 lysine. Fish fed diets containing 16.1 and 19.6 g kg-1 digestible lysine showed lower body lipid contents than fish in the other treatments. The digestible lysine requirement as determined by the broken-line model, based on average WG values, was 16.4 g kg-1. The other essential amino acid requirements were estimated based on the ideal protein concept and the value determined for lysine.

Diet formulation techniques and lysine requirements of 1- to 22-day-old broilers

Siqueira, J. C.; Sakomura, N. K.; Dourado, L. R B; Ezequiel, J. M B; Barbosa, N. A A; Fernandes, J. B K
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 123-134
ENG
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Two experiments were carried out to compare two techniques (amino acid supplementation and dilution) for formulating experimental diets for pre-starter (1 to 8 days) and starter (8 to 22 days) broiler chicks and to estimate digestible lysine requirements using the doseresponse method. In each experiment, 1,200 male Cobb 500 chickens were randomly distributed according to a 5×2 factorial arrangement (lysine level x formulation technique) with six replicates of 20 birds each. For the supplemented diet, a basal diet was formulated to meet the nutritional requirements, then L-lysine HCl was added to achieve digestible lysine levels of 0.975, 1.082, 1.189, 1.296 and 1.403% in the pre-starter diets and 0.840, 0.932, 1.024, 1.116 and 1.208% in the starter diets. For the diluted diet, a diet high in crude protein (CP) and relatively low in lysine was formulated and to which was added a protein-free diet until lysine levels were similar to those described above for the supplemented diet. The results suggest that the dilution technique favored the performance potential and better met lysine requirements compared with the supplementation technique. Lysine levels required for optimal feed conversion ratio of broilers during the pre-starter and starter phases were estimated at 1.361 and 1.187%...

Enhancing effect of lysine combined with other compounds on cephamycin C production in Streptomyces clavuligerus

Leite, Carla A.; Cavallieri, Andre P.; Araujo, Maria L. G. C.
Fonte: Biomed Central Ltd. Publicador: Biomed Central Ltd.
Tipo: Artigo de Revista Científica Formato: 11
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 05/55079-4; Processo FAPESP: 08/52819-5; Processo FAPESP: 13/02632-4; Background: Lysine plays an important role in Streptomyces clavuligerus metabolism; it takes part in its catabolism, via cadaverine, and in its secondary metabolism, in which lysine is converted via 1-piperideine-6-carboxylate to alpha-aminoadipic acid, a beta-lactam antibiotic precursor. The role of lysine as an enhancer of cephamycin C production, when added to production medium at concentrations above 50 mmol l(-1), has already been reported in the literature, with some studies attributing a positive influence to multifunctional diamines, among other compounds. However, there is a lack of research on the combined effect of these compounds on antibiotic production.Results: Results from experimental design-based tests were used to conduct response surface-based optimization studies in order to investigate the synergistic effect of combining lysine with cadaverine, putrescine, 1,3-diaminopropane, or alpha-aminoadipic acid on cephamycin C volumetric production. Lysine combined with cadaverine influenced production positively, but only at low lysine concentrations. On the whole, higher putrescine concentrations (0.4 g l(-1)) affected negatively cephamycin C volumetric production. In comparison to culture media containing only lysine as additive...

Diet formulation techniques and lysine requirements of 1-to 22-day-old broilers

Siqueira, J. C.; Sakomura, N. K.; Dourado, L. R. B.; Ezequiel, J. M. B.; Barbosa, N. A. A.; Fernandes, J. B. K.
Fonte: Facta-fundacio Arnco Ciência Tecnologia Avicolas Publicador: Facta-fundacio Arnco Ciência Tecnologia Avicolas
Tipo: Artigo de Revista Científica Formato: 123-134
ENG
Relevância na Pesquisa
358.16555%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Two experiments were carried out to compare two techniques (amino acid supplementation and dilution) for formulating experimental diets for pre-starter (1 to 8 days) and starter (8 to 22 days) broiler chicks and to estimate digestible lysine requirements using the dose-response method. In each experiment, 1,200 male Cobb 500 chickens were randomly distributed according to a 5x2 factorial arrangement (lysine level x formulation technique) with six replicates of 20 birds each. For the supplemented diet, a basal diet was formulated to meet the nutritional requirements, then L-lysine HCl was added to achieve digestible lysine levels of 0.975, 1.082, 1.189, 1.296 and 1.403% in the pre-starter diets and 0.840, 0.932, 1.024, 1.116 and 1.208% in the starter diets. For the diluted diet, a diet high in crude protein (CP) and relatively low in lysine was formulated and to which was added a protein-free diet until lysine levels were similar to those described above for the supplemented diet. The results suggest that the dilution technique favored the performance potential and better met lysine requirements compared with the supplementation technique. Lysine levels required for optimal feed conversion ratio of broilers during the pre-starter and starter phases were estimated at 1.361 and 1.187%...

Síntese e degradação de lisina em organismos superiores : uma possível origem bacteriana; Synthesis and degradation of lysine in higher organisms : a possible bacterial origin

Guilherme Coutinho de Melo Serrano
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 22/02/2010 PT
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357.599%
A lisina é considerada um aminoácido essencial, pois é componente fundamental de proteínas e não pode ser sintetizado por animais, sendo necessário ingeri-lo em sua forma final. Sua concentração é baixa em cereais, principal fonte de alimento animal e sua carência pode trazer sérios danos ao organismo, principalmente relacionados ao sistema nervoso. Por outro lado, seu excesso, causado pela deficiência na degradação, também é danoso podendo levar ao retardo no desenvolvimento mental. A síntese da lisina em plantas e bactérias é realizada principalmente pela via do ácido aspártico, que além desse aminoácido é responsável pela produção de treonina, metionina e isoleucina. A degradação da lisina em animais e plantas ocorre principalmente pela via da sacaropina. Essa via, por sua vez, é utilizada para a síntese de lisina em fungos. Assim, tanto a síntese como a degradação de lisina em diferentes organismos possuem arquiteturas metabólicas particulares que, durante o processo evolutivo, foram selecionadas para adequar-se as necessidades do metabolismo, diferenciação e desenvolvimento. Até o momento não existia indício da existência e da funcionalidade da via do ácido aspártico em animais e nem da via da sacaropina em bactérias. O presente trabalho apresenta um conjunto de resultados que sugerem a existência da via do ácido aspártico em insetos e a via da sacaropina em bactérias. Foram identificados em Anopheles gambie e Aedes aegypti...

Are high-lysine cereal crops still a challenge?

Ferreira,R.R.; Varisi,V.A.; Meinhardt,L.W.; Lea,P.J.; Azevedo,R.A.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2005 EN
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The essential amino acids lysine and threonine are synthesized in higher plants via a pathway starting with aspartate that also leads to the formation of methionine and isoleucine. Lysine is one of most limiting amino acids in plants consumed by humans and livestock. Recent genetic, molecular, and biochemical evidence suggests that lysine synthesis and catabolism are regulated by complex mechanisms. Early kinetic studies utilizing mutants and transgenic plants that over-accumulate lysine have indicated that the major step for the regulation of lysine biosynthesis is at the enzyme dihydrodipicolinate synthase. Despite this tight regulation, recent strong evidence indicates that lysine catabolism is also subject to control, particularly in cereal seeds. The challenge of producing crops with a high-lysine concentration in the seeds appeared to be in sight a few years ago. However, apart from the quality protein maize lines currently commercially available, the release of high-lysine crops has not yet occurred. We are left with the question, is the production of high-lysine crops still a challenge?

Lysine supplementation in late gestation of gilts: effects on piglet birth weight, and gestational and lactational performance

Magnabosco,Diogo; Bierhals,Thomas; Ribeiro,Renato Rosa; Cemin,Henrique Scherer; Faccin,Jamil Elias Ghiggi; Bernardi,Mari Lourdes; Wentz,Ivo; Bortolozzo,Fernando Pandolfo
Fonte: Universidade Federal de Santa Maria Publicador: Universidade Federal de Santa Maria
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2013 EN
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Lysine requirements for gain in maternal body reserves and piglet birth weight, during pregnancy, in contemporary prolific genotypes, are not well established. This study aimed to evaluate the effect of dietary lysine in late pregnancy on piglet birth weight, and on the gestational and lactational performance of gilts. Pregnant gilts were uniformly distributed into two groups and received, from 85 to 110 days of gestation, either of two lysine levels in their diet: Control group - 28g lysine/day (n=136), and Lysine group - 35g lysine/day (n=141). There were no effects (P>0.10) of supplemental lysine on body weight and backfat (BF) gain of females or on piglet birth weight. Gilts supplemented with lysine tended to have a lower percentage of stillbirths (P=0.077), reduced within-litter birth weight variation (P=0.094) and a lower percentage of piglets weighing less than 1100g (P=0.082) than in the Control group. During lactation, the performance of sows and litters was also evaluated in a subgroup of sows (n=26/group). There were no differences between the Control and Lysine groups (P>0.10) in voluntary feed intake, body reserve losses (weight and BF), weaning-to-estrus interval of the sows, and litter weaning weight. In conclusion, an increase in lysine (from 28 to 35g/day) in late gestation of gilts (85 to 110 days) tends to reduce the rate of stillbirths and to improve the uniformity of litter weight at birth...

Crude protein reduction and digestible methionine+cystine and threonine to digestible lysine ratios in diets for Nile tilapia fingerlings

Quadros,Moisés; Lanna,Eduardo Arruda Teixeira; Donzele,Juarez Lopes; Abreu,Márvio Lobão Teixeira de; Ribeiro,Felipe Barbosa; Takishita,Sylvia Sanae
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2009 EN
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The objective of the present study was to investigate crude protein reduction and the methionine+cystine and threonine to lysine ratios in diets for reversed Nile tilapia fingerlings (Oreochromis niloticus), Thai strain. Four hundred and twenty Nile tilapia fingerlings with an average initial weight of 1.83 ± 0.02 g were placed in a completely randomized design, with five treatments, seven replications per treatment and 12 fish per experimental unit, for 37-days. Two crude protein (CP) levels were evaluated (32 and 28%). The diet with 32% CP had methionine+cystine:lysine and threonine:lysine ratios of 63 and 74%, respectively. Three diets with 28% CP had methionine+cystine:lysine and threonine:lysine ratios of 63 and 74%, 60 and 74% and 60 and 69%, respectively. The diet with 28% CP and had methionine+cystine:lysine ratio of 63% and threonine:lysine of 74% and was supplemented with 0.3% glutamic acid. The fish were kept in thirty-five 130 L aquariums supplied with single-pass flow-through water, individual aeration and fed ad libitum six times per day. Fish fed the diet with 32% CP had lower protein efficiency ratios and nitrogen efficiency ratios. The diet CP level was 28% and the methionine+cystine and threonine to lysine ratios were 60 and 69%...

Starter dietary lysine level and strain cross effects on performance and carcass traits of broiler females

Corzo,A; Kidd,MT
Fonte: Fundação APINCO de Ciência e Tecnologia Avícolas Publicador: Fundação APINCO de Ciência e Tecnologia Avícolas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2004 EN
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Dietary lysine has been shown to impact the performance of broilers, particularly with aspect of breast meat accretion and yield. There have been studies that suggest that early dietary lysine has an effect on breast meat yield in male broilers. A study was designed to evaluate starter dietary lysine (1.20 vs 1.35% of diet as achieved by the addition of L-lysine at the expense of a filler) effect on performance of female broilers from three different genetic strain crosses, and monitor subsequent effects at 41 and 56 d of age. Body weight and feed consumption were higher for birds consuming the high lysine starter diet, but feed conversions were similar when compared to the low lysine diet. Body weight and feed conversion were similar among strains. Mortality was unaffected by lysine level and strain cross. Carcass and breast meat weight, but not yields, were higher in birds fed the high lysine diet. At 56 d differences in carcass yield, abdominal fat, and breast meat yield were seen among strains, such that the strain with highest yield had the least amount of abdominal fat in terms of absolute weight and percentage. No effect on processing yields by dietary lysine was observed at any time regardless of the growing characteristics of the broilers. However...

Effects of lysine levels of diets formulated based on total or digestible amino acids on broiler carcass composition

Nasr,J; Kheiri,F
Fonte: Fundação APINCO de Ciência e Tecnologia Avícolas Publicador: Fundação APINCO de Ciência e Tecnologia Avícolas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 EN
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The study was conducted to evaluate carcass yield and chemical composition of thigh and breast muscles of broilers fed three different lysine requirement levels: high lysine (+10% NRC), standard (NRC) and low lysine (-10% NRC) and two ways of expressing amino acids in feedstuffs (total or digestible amino acids). The results of this study showed that diet formulation based on digestible amino acids significantly influenced breast yield and abdominal fat deposition. The study showed that increasing lysine level (+10% NRC) of diet significantly increased both carcass and breast percentage and also carcass, breast and thigh weight. The interaction between digestible amino acids and lysine requirement levels affected carcass and breast percentage. Feeding broilers high lysine diets (+10% NRC) significantly increased lysine content in breast and thigh. The response to formulation based on digestible amino acids was maximized when broilers received the high lysine level diet.

Diet formulation techniques and lysine requirements of 1- to 22-day-old broilers

Siqueira,JC; Sakomura,NK; Dourado,LRB; Ezequiel,JMB; Barbosa,NAA; Fernandes,JBK
Fonte: Fundação APINCO de Ciência e Tecnologia Avícolas Publicador: Fundação APINCO de Ciência e Tecnologia Avícolas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
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358.16555%
Two experiments were carried out to compare two techniques (amino acid supplementation and dilution) for formulating experimental diets for pre-starter (1 to 8 days) and starter (8 to 22 days) broiler chicks and to estimate digestible lysine requirements using the dose-response method. In each experiment, 1,200 male Cobb 500 chickens were randomly distributed according to a 5x2 factorial arrangement (lysine level x formulation technique) with six replicates of 20 birds each. For the supplemented diet, a basal diet was formulated to meet the nutritional requirements, then L-lysine HCl was added to achieve digestible lysine levels of 0.975, 1.082, 1.189, 1.296 and 1.403% in the pre-starter diets and 0.840, 0.932, 1.024, 1.116 and 1.208% in the starter diets. For the diluted diet, a diet high in crude protein (CP) and relatively low in lysine was formulated and to which was added a protein-free diet until lysine levels were similar to those described above for the supplemented diet. The results suggest that the dilution technique favored the performance potential and better met lysine requirements compared with the supplementation technique. Lysine levels required for optimal feed conversion ratio of broilers during the pre-starter and starter phases were estimated at 1.361 and 1.187%...

Lysine catabolism: flow, metabolic role and regulation

Fornazier,Ricardo Francisco; Azevedo,Ricardo Antunes; Ferreira,Renato Rodrigues; Varisi,Vanderlei Aparecido
Fonte: Brazilian Journal of Plant Physiology Publicador: Brazilian Journal of Plant Physiology
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2003 EN
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Lysine is an essential amino acid, synthesized in plants in the aspartic acid pathway. The lysine catabolism is performed by the action of two consecutive enzymes, lysine 2-oxoglutarate reductase (LOR) and saccharopine dehydrogenase (SDH). The steady state of lysine is controlled by both, synthesis and catabolism rates, with the final soluble lysine concentration in cereal seeds a direct result of these processes. In the last 40 years, the enzymes involved in lysine biosynthesis have been purified and characterized from some plant species such as carrot, maize, barley, rice, and coix. Recent reports have revealed that lysine degradation might be related to various physiological processes, for instance growth, development and response to environmental changes and stress. The understanding of the regulatory aspects of the lysine biosynthetic and catabolic pathways and manipulation of related enzymes is important for the production of high-lysine plants.

Evaluation of umbilical cord mesenchymal stem cell labeling with superparamagnetic iron oxide nanoparticles coated with dextran and complexed with Poly-L-lysine

Sibov,Tatiana Taís; Miyaki,Liza Aya Mabuchi; Mamani,Javier Bustamante; Marti,Luciana Cavalheiro; Sardinha,Luiz Roberto; Pavon,Lorena Favaro; Oliveira,Daniela Mara de; Cardenas,Walter Humberto; Gamarra,Lionel Fernel
Fonte: Instituto Israelita de Ensino e Pesquisa Albert Einstein Publicador: Instituto Israelita de Ensino e Pesquisa Albert Einstein
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
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OBJECTIVE: The objective of this study was to evaluate the effect of the labeling of umbilical cord vein derived mesenchymal stem cells with superparamagnetic iron oxide nanoparticles coated with dextran and complexed to a non-viral transfector agent transfector poly-L-lysine. METHODS: The labeling of mesenchymal stem cells was performed using the superparamagnetic iron oxide nanoparticles/dextran complexed and not complexed to poly-L-lysine. Superparamagnetic iron oxide nanoparticles/dextran was incubated with poly-L-lysine in an ultrasonic sonicator at 37°C for 10 minutes for complex formation superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine by electrostatic interaction. Then, the mesenchymal stem cells were incubated overnight with the complex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine and superparamagnetic iron oxide nanoparticles/dextran. After the incubation period the mesenchymal stem cells were evaluated by internalization of the complex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine and superparamagnetic iron oxide nanoparticles/dextran by Prussian Blue stain. Cellular viability of labeled mesenchymal stem cells was evaluated by cellular proliferation assay using 5,6-carboxy-fluorescein-succinimidyl ester method and apoptosis detection by Annexin V- Propidium Iodide assay. RESULTS: mesenchymal stem cells labeled with superparamagnetic iron oxide nanoparticles/dextran without poly-L-lysine not internalized efficiently the superparamagnetic iron oxide nanoparticles due to its low presence detected within cells. Mesenchymal stem cells labeled with the complex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine efficiently internalized the superparamagnetic iron oxide nanoparticles due to greater presence in the cells interior. The viability and apoptosis assays demonstrated that the mesenchymal stem cells labeled and not labeled respectively with the superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine continue to proliferate over seven days and the percentage of cells in early or late apoptosis is low compared to the percentage of live cells over the three days. CONCLUSION: Our results showed that the use of poly-L-lysine complexed with superparamagnetic iron oxide nanoparticles/dextran provides better internalization of these superparamagnetic iron oxide nanoparticles in mesenchymal stem cells Thus...

Influência da suplementação de lisina no terço final da gestação sobre o desempenho de primíparas suínas e sua leitegada; Influence of lysine suplementation in late gestation on sow and piglet performance

Magnabosco, Diogo
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
359.05926%
O estudo avaliou a inclusão de Lisina, o primeiro aminoácido limitante na dieta dos suínos, no terço final da gestação de primíparas suínas, e os efeitos em relação ao desempenho das fêmeas e de suas leitegadas ao nascer e o impacto no período lactacional subsequente. Foram selecionadas 298 leitoas, aos 85 dias de gestação, distribuídas uniformemente em dois grupos de acordo com idade de cobertura, peso, escore corporal visual (ECV) e espessura de toucinho (ET), sendo os grupos: Controle - 3,3 kg/ração/fêmea/dia, com 0,84% de lisina, correspondendo a um consumo diário de 28 g/lisina/fêmea e Lisina – 3,3 kg/ração/fêmea/dia, com 0,84% de lisina, mais o acréscimo de 7 g de lisina (correspondendo a um consumo diário de 35 g/lisina/fêmea). O fornecimento de lisina foi feito de forma “on top” dos 85 dias de gestação até o momento de transferência para a maternidade (110 dias de gestação). Foram efetuadas as medidas de peso e ET no momento de transferência para a maternidade. No parto, os leitões nascidos vivos (NV) e natimortos (NAT) foram quantificados e pesados individualmente em até 12 horas após o nascimento, e os fetos mumificados (MUM) foram contabilizados e incluídos no número de leitões nascidos totais (NT). Na lactação foi avaliado o desempenho de 60 fêmeas e seus lactentes. Para isto...

Protein recycling in growing rabbits: contribution of microbial lysine to amino acid metabolism

Belenguer, Álvaro; Balcells, Joaquín; Guada, Jose A.; Decoux, Marc; Milne, Eric
Fonte: Cambridge University Press Publicador: Cambridge University Press
Tipo: Artículo Formato: 199204 bytes; application/pdf
ENG
Relevância na Pesquisa
357.599%
8 pages, 6 tables, 2 figures.-- PMID: 16277780 [PubMed]; To study the absorption of microbial lysine in growing rabbits, a labelled diet (supplemented with (15)NH4Cl) was administered to six animals (group ISOT); a control group (CTRL, four rabbits) received a similar, but unlabelled, diet. Diets were administered for 30 d. An additional group of six animals were fed the unlabelled diet for 20 d and then the labelled diet for 10 d while wearing a neck collar to avoid caecotrophy (group COLL), in order to discriminate it from direct intestinal absorption. At day 30 animals were slaughtered and caecal bacteria and liver samples taken. The (15)N enrichment in amino acids of caecal bacteria and liver were determined by GC-combustion/isotope ratio MS. Lysine showed a higher enrichment in caecal microflora (0.925 atom% excess, APE) than liver (0.215 APE) in group ISOT animals, confirming the double origin of body lysine: microbial and dietary. The COLL group showed a much lower enrichment in tissue lysine (0.007 (se 0.0029) APE for liver). Any enrichment in the latter animals was due to direct absorption of microbial lysine along the digestive tract, since recycling of microbial protein (caecotrophy) was avoided. In such conditions liver enrichment was low...

Diet formulation techniques and lysine requirements of 1-to 22-day-old broilers

Siqueira, J. C.; Sakomura, N. K.; Dourado, L. R. B.; Ezequiel, J. M. B.; Barbosa, N. A. A.; Fernandes, J. B. K.
Fonte: Facta-fundacio Arnco Ciência Tecnologia Avicolas Publicador: Facta-fundacio Arnco Ciência Tecnologia Avicolas
Tipo: Artigo de Revista Científica Formato: 123-134
ENG
Relevância na Pesquisa
358.16555%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Two experiments were carried out to compare two techniques (amino acid supplementation and dilution) for formulating experimental diets for pre-starter (1 to 8 days) and starter (8 to 22 days) broiler chicks and to estimate digestible lysine requirements using the dose-response method. In each experiment, 1,200 male Cobb 500 chickens were randomly distributed according to a 5x2 factorial arrangement (lysine level x formulation technique) with six replicates of 20 birds each. For the supplemented diet, a basal diet was formulated to meet the nutritional requirements, then L-lysine HCl was added to achieve digestible lysine levels of 0.975, 1.082, 1.189, 1.296 and 1.403% in the pre-starter diets and 0.840, 0.932, 1.024, 1.116 and 1.208% in the starter diets. For the diluted diet, a diet high in crude protein (CP) and relatively low in lysine was formulated and to which was added a protein-free diet until lysine levels were similar to those described above for the supplemented diet. The results suggest that the dilution technique favored the performance potential and better met lysine requirements compared with the supplementation technique. Lysine levels required for optimal feed conversion ratio of broilers during the pre-starter and starter phases were estimated at 1.361 and 1.187%...