6-pyruvoyl tetrahydropterin synthase/QueD family (IPR007115)

Short name: 6-PTP_synth/QueD

Overlapping homologous superfamilies

Family relationships


6-Pyruvoyl tetrahydrobiopterin synthase (PTPS) catalyses the conversion of dihydroneopterin triphosphate to 6-pyruvoyl tetrahydropterin, the second of three enzymatic steps in the synthesis of tetrahydrobiopterin from GTP [PMID: 8137809]. The functional enzyme is a hexamer of identical subunits. A transition metal binding site formed by the three histidine residues 23, 48 and 50 is present in each subunit, and bound Zn(II) is responsible for the enzymatic activity. Site-directed mutagenesis of each of these three histidine residues results in a complete loss of metal binding and enzymatic activity [PMID: 7563095, PMID: 9165069].

The function of the bacterial branch of the family had been thought to be the same, but many are now taken to be QueD, and enzyme of queuosine biosynthesis. Queuosine is a hypermodified base in the wobble position of some tRNAs in most species [PMID: 14660578].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.