Biochemical and Molecular Characterization of a Mutation That Confers a Decreased Raffinosaccharide and Phytic Acid Phenotype on Soybean Seeds
AUTOR(ES)
Hitz, William D.
FONTE
American Society of Plant Physiologists
RESUMO
A single, recessive mutation in soybean (Glycine max L. Merr.), which confers a seed phenotype of increased inorganic phosphate, decreased phytic acid, and a decrease in total raffinosaccharides, has been previously disclosed (S.A. Sebastian, P.S. Kerr, R.W. Pearlstein, W.D. Hitz [2000] Soy in Animal Nutrition, pp 56–74). The genetic lesion causing the multiple changes in seed phenotype is a single base change in the third base of the codon for what is amino acid residue 396 of the mature peptide encoding a seed-expressed myo-inositol 1-phospate synthase gene. The base change causes residue 396 to change from lysine to asparagine. That amino acid change decreases the specific activity of the seed-expressed myo-inositol 1-phosphate synthase by about 90%. Radio tracer experiments indicate that the supply of myo-inositol to the reaction, which converts UDP-galactose and myo-inositol to galactinol is a controlling factor in the conversion of total carbohydrate into the raffinosaccharides in both wild-type and mutant lines. That same decrease in myo-inositol 1-phosphate synthetic capacity leads to a decreased capacity for the synthesis of myo-inositol hexaphosphate (phytic acid) and a concomitant increase in inorganic phosphate.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=148927Documentos Relacionados
- The Timing and Rate of Phytic Acid Accumulation in Developing Soybean Seeds 1
- Origin and Seed Phenotype of Maize low phytic acid 1-1 and low phytic acid 2-11
- Effect of Thymol on Soybean Seeds Germination: Physiological and Biochemical Analysis
- Characterization of a mutation in the parE gene that confers fluoroquinolone resistance in Streptococcus pneumoniae.
- Biochemical changes associated to soybean seeds osmoconditioning during storage.