|
|
|
|
| |
|
|
| Toro,Alejandro Alberto; Medici,Leonardo Oliveira; Sodek,Ladaslav; Lea,Peter John; Azevedo,Ricardo Antunes. |
| For human nutrition the main source of vegetable proteins are cereal and legume seeds. The content of total soluble amino acids in mature endosperm of wild-type, opaque and floury maize (Zea mays L.) mutants were determined by HPLC. The total absolute concentration of soluble amino acids among the mutants varied depending on the mutant. The o11 and o13 mutants exhibited the highest average content, whereas o10, fl3 and fl1 exhibited the lowest average content. In general, the mutants exhibited similar concentrations of total soluble amino acids when compared to the wild-type lines, with the clear exception of mutants o11 and fl1, with the o11 mutant exhibiting a higher concentration of total soluble amino acids when compared to its wild-type counterpart... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Zea mays; Lysine; Threonine; Methionine. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162003000100014 |
| |
|
|
| Ferreira,Renato Rodrigues; Vendemiatti,Ariane; Meinhardt,Lyndel Wayne; Lea,Peter John; Azevedo,Ricardo Antunes. |
| Cereal seeds are poor in essential amino acids, particularly lysine, tryptophan and threonine. The amino acids lysine and threonine are synthesized in the aspartate pathway. Although most of the enzymes of the aspartate pathway have been isolated and characterized in higher plant species, the metabolism of lysine and threonine is totally unknown in sorghum. We have isolated two enzymes, aspartate kinase (AK) and homoserine dehydrogenase (HSDH) from sorghum. Optimum assay conditions were established for the determination of AK and HSDH activities. The highest level of activity was observed in immature seeds. AK was shown to be inhibited by threonine and lysine indicating the existence of at least two isoenzymes, one sensitive to threonine inhibition and the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Amino acids; Aspartate kinase; Homoserine dehydrogenase; Lysine; Threonine. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000200005 |
| |
|
|
| Molina,Silvia Maria Guerra; Gaziola,Salete Aparecida; Lea,Peter John; Azevedo,Ricardo Antunes. |
| A lisina é um aminoácido essencial cuja via de biossíntese faz parte da via metabólica do ácido aspártico, pela qual são também sintetizados os aminoácidos treonina, metionina e isoleucina. Além disso, a lisina é o principal aminoácido limitante em todos os cereais e por cerca de 30 anos a via do ácido aspártico tem sido estudada em plantas, com o intuito de desvendar e caracterizar os principais pontos chave na regulação das vias de biossíntese desses aminoácidos. Duas etapas distintas, uma primeira originada a partir do desenvolvimento da cultura de tecidos (anos 70-80) e a segunda a partir do desenvolvimento de técnicas para a transformação de plantas (anos 90), permitiram que mutantes bioquímicos e plantas trangênicas fossem produzidos com alterações... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lisina; Nutrição; Aminoácidos essenciais; Cereais. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162001000100032 |
| |
|
|
| Gratão,Priscila Lupino; Prasad,Majeti Narasimha Vara; Cardoso,Patrícia Felippe; Lea,Peter John; Azevedo,Ricardo Antunes. |
| The contamination of the environment by toxic metals poses a threat for "Man and biosphere", reducing agricultural productivity and damaging the health of the ecosystem. In developed nations, this problem is being addressed and solved to some extent by using "green technology" involving metal tolerant plants, to clean up the polluted soils. The use of naturally occurring metal tolerant plants and the application of genetic manipulation, should hasten the process of transferring this technology from laboratory to field. Therefore, it is essential to investigate and understand how plants are able to tolerate toxic metals and to identify which metabolic pathways and genes are involved in such a process. Recent advances in knowledge derived from the "omics",... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Hyperaccumulator plants; Phytoremediation; Toxic metals. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000100005 |
| |
|
|
|
