What is the function of dihydropteridine reductase?
Dihydropteridine reductase (DHPR) is an enzyme essential for the regeneration of tetrahydrobiopterin, itself a co-factor necessary for the hydroxylation reactions in the brain leading to the synthesis of tyrosine, dopa, noradrenaline and 5-hydroxytryptophan (Fig. 1).
What is folate synthase?
In plants, folate synthesis presents a complex spatial organization, in which three subcellular compartments participate: the pterin part of the molecule is synthesized from GTP in the cytosol, pABA is synthesized from chorismate in plastids and the combination of pterin, pABA and glutamate is made within mitochondria …
What is the function of Dihydropteroate synthase?
Dihydropteroate synthetase catalyzes the reaction that combines pteridine precursors with PABA to make folic acid. Thus, sulfonamides prevent the synthesis of bacterial folic acid, an essential cofactor for bacterial nucleic acid synthesis.
What is the DHPS enzyme?
Dihydropteroate synthase (DHPS) catalyzes the condensation of 6-hydroxymethyl-7,8-dihydropteridine pyrophosphate to para-aminobenzoic acid (PABA) to form 7,8-dihydropteroate. DHPs is a key enzyme in folate synthesis. Folate is necessary for nucleic acid synthesis. DHPS is found in bacteria and not in eukaryotes.
What is malignant PKU?
A small percentage of children with elevated phenylalanine levels exhibit normal PAH levels but have a deficiency in synthesis or recycling of BH4 known as tetrahydrobiopterin deficiency. This condition is sometimes termed malignant PKU and can result from biallelic mutations in the GCH1, PCB1, PTS, or QDPR genes.
What is PABA in microbiology?
para-aminobenzoic acid (PABA), also called aminobenzoic acid, a vitamin-like substance and a growth factor required by several types of microorganisms. In bacteria, PABA is used in the synthesis of the vitamin folic acid.
What is the role of phenylalanine hydroxylase?
Normal Function Phenylalanine hydroxylase is responsible for the conversion of phenylalanine to another amino acid, tyrosine. The enzyme works with a molecule called tetrahydrobiopterin (BH4) to carry out this chemical reaction.
