The brain damage which occurs in untreated phenylketonuria probably results from the high plasma phenylalanine concentration prevailing in this condition, as treatment with a low-phenylalanine diet mitigates the situation. The actual cause of the brain damage is not known, but investigations have been carried out with high phenylalanine loads to simulate phenylketonuria and so elucidate the nat...

UNLABELLED The effect of energy, protein, fat, and phenylalanine on serum phenylalanine concentrations during pregnancy for a set of identical twins with phenylketonuria (PKU) was examined. Blood samples were collected one to two times per week. The subjects completed a 3-d food record prior to each blood collection. The effect of the factors on serum phenylalanine levels was evaluated statisti...

Phenylketonuria (PKU) is the most common autosomal recessive disorder of amino acid metabolism. Thedisease is caused mainly by mutations in the phenylalanine hydroxylase (PAH) gene, encoding phenylalaninehydroxylase (PAH) enzyme. The PAH enzyme deficiency results in the elevation of phenylalanine inthe blood, which may cause severe irreversible mental retardation in the affect...

Conway, T. W. (The University of Texas, Austin), E. M. Lansford, Jr., and W. Shive. Influence of phenylalanine analogues upon bacterial accumulation and incorporation of phenylalanine. J. Bacteriol. 85:141-149. 1963.-Phenylalanine accumulation and its relation to phenylalanine incorporation into trichloroacetic acid-insoluble material in Escherichia coli 9723 were studied with a variety of stru...

The role of hyperthermia during regional alkylating agent chemotherapy is controversial. The aim of this study was to determine the exact contribution of hyperthermia to tumor response during isolated limb infusion with l-phenylalanine mustard. Rats bearing rodent fibrosarcoma on the hindlimb underwent isolated limb infusion with saline, saline plus heat, l-phenylalanine mustard, l-phenylalanin...

Calculation of rates of protein synthesis, based upon incorporation of [14C]phenylalanine into protein, depended upon use of the specific activity of phenylalanyl-tRNA. At a perfusate phenylalanine concentration of 0.01 mM, the specific activity of phenylalanyl-tRNA was 65 and 155% of extracellular and intracellular specific activities, respectively. At this concentration, the rate of protein s...

Phenylalanine ammonia-lyase, which irreversibly deaminates phenylalanine and tyrosine, markedly inhibited the growth of human leukemic and murine L5178Y lymphoblasts in vitro but had a negligible effect on resting (nondividing) normal lymphocytes. These studies also demonstrated that phenylalanine ammonia-lyase inhibited DNA synthesis in leukemic cells at least as effectively as did asparaginas...

Self-assembly of phenylalanine is linked to amyloid formation toxicity in phenylketonuria disease. We are demonstrating that L-phenylalanine self-assembles to amyloid fibrils at varying experimental conditions and transforms to a gel state at saturated concentration. Biophysical methods including nuclear magnetic resonance, resistance by alpha-phenylglycine to fibril formation and preference of...