Effect of metals and phenylalanine on the activity of human tryptophan hydroxylase-2: comparison with that on tyrosine hydroxylase activity.

Article Details

Citation

Copy to clipboard

Ogawa S, Ichinose H

Effect of metals and phenylalanine on the activity of human tryptophan hydroxylase-2: comparison with that on tyrosine hydroxylase activity.

Neurosci Lett. 2006 Jul 3;401(3):261-5. Epub 2006 Apr 11.

PubMed ID

16581181 [ View in PubMed

]

Abstract

We cloned the human tryptophan hydroxylase-2 (hTPH2) gene by RT-PCR, and expressed and purified its product as a maltose-binding protein (MBP)-fusion protein. We investigated the effects of essential divalent cations and L-phenylalanine (L-Phe) on the hTPH2 activity for the first time, and compared them with those on human tyrosine hydroxylase (hTH1) activity. We found that cobaltous and manganous ions inhibited the activities of both enzymes but that hTH1 was affected at lower concentrations than hTPH2. From kinetic analyses, we found that phenylalanine acted as an inhibitor more strongly against hTPH2 than against hTH1. These data are important for elucidating the molecular mechanism underlying the alterations in the contents of serotonin and catecholamines in the brain under pathological and physiological conditions, such as hyperphenylalaninemia and chronic manganese toxicity.

DrugBank Data that Cites this Article

Drug Targets

Drug	Target	Kind	Organism	Pharmacological Action	Actions
Phenylalanine	Tyrosine 3-monooxygenase	Protein	Humans	Unknown	Binder	Details