Studies were carried out to elucidate the mechanisms underlying the diminished phosphorylation of cerebral ribosomal protein in experimental hyperphenylalaninaemia [Roberts & Morelos (1980) Biochem. J.190, 405-419]. Administration of N(6),O(2)'-dibutyryl cyclic AMP or 3-isobutyl-1-methylxanthine, which increased phosphorylation of the S6 protein of cerebral 40S ribosomal subunits in control inf...

The L-type amino acid transporter 1 (LAT1) is an Na(+)-independent neutral amino acid transporter subserving the amino acid transport system L. Because of its broad substrate selectivity, system L has been proposed to be responsible for the permeation of amino acid-related drugs through the plasma membrane. To understand the mechanisms of substrate recognition, we have examined the LAT1-mediate...

Phenethyl alcohol inhibits the growth of many microorganisms. It is believed that the growth inhibition is mediated by its effect on the cell membrane. Differences between sensitive and resistant strains are suggested to be due to alterations in membrane structure. We report that, in some strains, an unexpected relationship exists between auxotrophy for tryptophan, tyrosine and phenylalanine an...

Free amino acids of cerebrospinal fluid and serum in hepatic coma have been studied. Citrulline was found to form about 80% of the total free amino acids in cerebrospinal fluid, whereas serum contained slightly higher levels of tyrosine, methionine, phenylalanine and glutamine. The higher level of citrulline in cerebrospinal fluid may be attributed to the inhibition of argininosuccinic acid syn...

background there is evidence in support of low bone density in young patients with disorders of phenylalanine metabolism; however, little is known about muscle and fat mass in these patients, especially in those with mild hyperphenylalaninemia (mhpa). objectives we aimed to evaluate body composition of children and adolescents with early-diagnosed disorders of phenylalanine metabolism. patients...

M I C E homozygous for the dilute-lethal (8) gene have been reported by COLEMAN (1960) and RAUCH and YOST (1963) to have low liver phenylalanine hydroxylase activity. This deficiency in phenylalanine metabolism has been reported to be due to the presence of an inhibitor of the hydroxylase localized in a particulate fraction of liver (15,000 x g sediment). These investigators have pointed out th...

The interaction of the cysteine conjugate S-(1-chloro-1,2,2, -trifluoroethyl)-L-cysteine (CTFC) with organic anion and amino acid transport in the basolateral and apical membranes was examined with rabbit renal proximal tubule suspensions and primary cultures of rabbit renal proximal tubule cells. The apparent K(i) for CTFC inhibition of the 1-min uptake of [(3)H]p-aminohippurate in tubule susp...