Stable isotope infusion methods have not been extensively used in horses to study protein metabolism. The objectives were to develop infusion and sampling methodologies for [1-(13)C] phenylalanine and apply these methods to determine whether the addition of supplemental amino acids to a control diet affected whole-body phenylalanine kinetics in mature horses. Arabian geldings were studied using...

The phosphorylation of human phenylalanine hydroxylase by cyclic AMP-dependent protein kinase was studied using recombinant enzyme expressed as a fusion protein in the pMAL system of Escherichia coli. Using the target sequence of the restriction protease enterokinase (Asp4-Lys) as the linker peptide, 100% full-length human phenylalanine hydroxylase was obtained on protease cleavage. The fusion ...

The transamination by pig mitochondrial and supernatant aspartate transaminase of aromatic amino acids was studied in order to determine if an analogy exists between these enzymes and a previously reported brain phenylalanine transaminase (GEORGE, H., AND GABAY, S. (1968) Biochim. Biophys. Ada, 167, 555). Supernatant and mitochondrial aspartate transaminase from pig heart can utilize aromatic a...

Cognitive and mental health problems in individuals with the inherited metabolic disorder phenylketonuria (PKU) have often been associated with metabolic control and its history. For the present study executive functioning (EF) was assessed in 21 PKU patients during childhood (T1, mean age 10.4 years, SD = 2.0) and again in adulthood (T2, mean age 25.8 years, SD = 2.3). At T2 additional assessm...

background: genetic diversity of three polymorphic markers in the phenylalanine hydroxylase (pah) gene region including pvu ii (a), pahstr and msp i were investigated. methods: unrelated individuals (n=139) from the iranian populations were genotyped using primers specific to pah gene markers including pvu ii(a), msp i and pahstr. the amplified products for pvu ii(a), msp i were digested using ...

Moderate doses of glucagon (20 micrograms/kg I.V.) are sufficient to stimulate rat hepatic phenylalanine hydroxylase in vivo. In addition, the stimulation of the tetrahydrobiopterin-dependent phenylalanine hydroxylase activity in livers of animals fed on a high-protein diet has been correlated with an elevated phosphate content. The tetrahydrobiopterin-dependent hydroxylase activity in these an...