Phenylalanine hydroxylase: Function, structure, and regulation

Mechanism of phenylalanine regulation of phenylalanine hydroxylase.

The mechanism of phenylalanine regulation of rat liver phenylalanine hydroxylase was studied. We show that phenylalanine "activates" phenylalanine hydroxylase, converting it from an inactive to active form, by binding at a true allosteric regulatory site. One phenylalanine molecule binds per enzyme subunit; it remains at this site during catalytic turnover and, while there, cannot be hydroxylat...

Regulation of Rat Liver Phenylalanine Hydroxylase

Effects of phenylalanine and diand tetrahydropterins on presteady-state and steady-state catalytic behavior of rat liver phenylalanine hydroxylase are analyzed. From this and previous work (Shiman, R, Xia, T., Hill, M., and Gray, D. (1994) J. BioZ. Chem. 269, 2464724656), which analyzed binding of the same compounds to the enzyme in the absence of catalysis, a model of phenylalanine hydroxylase...

Phenylalanine Hydroxylase, Tyrosine Hydroxylase, and Tryptophan Hydroxylase

Mouse phenylalanine hydroxylase. Homology and divergence from human phenylalanine hydroxylase.

The laboratory mouse represents an important model for the study of phenylalanine metabolism and the pathochemistry of phenylketonuria, yet mouse phenylalanine hydroxylase (PAH) has not been extensively studied. We report the cloning and sequencing of a mouse PAH cDNA, the expression of enzymic activity from the mouse PAH cDNA clone and the identification of mouse PAH and human PAH by two-dimen...

Evolution of Structure and Function in Phenylalanine Hydroxylase With the Regulatory Properties in Sight

In the post-genomic era, an idea of how similar the genomes of different species actually are is on the horizon. Less than 10 years ago, the human genome was estimated to encode 100000 genes. That was an overestimation, as the real number of human genes is 20000-25000. Most genes are expressed as proteins. The 3D structure of a protein is more conserved than its sequence, and therefore the stru...