Phenylketonuria (PKU) is a disease characterized by an inability to metabolize the amino acid l-phenylalanine. The resulting buildup leads to brain damage and ultimately mental retardation in children if their phenylalanine intake is not carefully controlled. The National Institutes of Health recently suggested that people with PKU monitor their phenylalanine levels throughout their life and be...

The conversion of prephenic acid to tyrosine can occur by two different routes: (a) oxidative decarboxylation (prephenate dehydrogenase) followed by transamination (aromatic aminotransferase); (b) transamination of prephenate forming the non-aromatic amino acid arogenic acid (prephenate aminotransferase) followed by oxidative decarboxylation (arogenate dehydrogenase). High activity of arogenate...

The regulation of tyrosine production in the anthramycin-producing organism Streptomyces refuineus var. thermotolerans has been studied with wild-type and tyrosine auxotrophic organisms. Growth of the auxotroph on minimal medium plus phenylalanine suggested that phenylalanine may increase the supply of tyrosine. In incubation with whole cells, tyrosine levels increased in response to added phen...

Abstract Chiral phenylglycinol is a very important chemical in the pharmaceutical manufacturing. Current methods for synthesis of chiral often suffered from unsatisfied selectivity, low product yield and using non-renewable resourced substrates, then remain grand challenge. Design construction synthetic microbial consortia promising strategy to convert bio-based materials into high value-added ...

l-Histidine and, to a lesser degree, l-phenylalanine at concentrations of 10(-4)m inhibit the growth of leaky mutants (bradytrophs) of Bacillus subtilis that are deficient in the synthesis of p-hydroxyphenylpyruvate, the first intermediate specific to tyrosine synthesis. The inhibition can be overcome by growth factor amounts of l-tyrosine and p-hydroxyphenylpyruvate. Histidine and phenylalanin...

Treatment of dogfish l& lactic dehydrogenase with carboxypeptidase A releases 1 mole of phenylalanine per 36,000 g of the enzyme and no other amino acids. A mixture of carboxypeptidases A and B releases 1 mole of phenylalanine and 1 mole of lysine per 36,000 g of the lactic dehydrogenase. The amino terminus of dogfish M4 lactic dehydrogenase does not react with either dansyl chloride or the Edm...

The effect of hyperphenylalaninaemia on the metabolism of ketone bodies in vivo and in vitro by developing rat brain was investigated. The incorporation in vivo of [14C]acetoacetate into cerebral lipids was decreased by both chronic (for 3 days) and acute (for 6h) hyperphenylalaninaemia induced by injecting phenylalanine into 1-week-old rats. In studies in vitro it was observed that the incorpo...

amino acid dehydrogenases (l-amino acid: oxidoreductase deaminating ec 1.4.1.x) are members of the wider superfamily of oxidoreductases that catalyze the reversible oxidative deamination of an amino acid to its keto acid and ammonia with the concomitant reduction of either nad+, nadp+ or fad. these enzymes have been received much attention as biocatalysts for use in biosensors or diagnostic kit...