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PROSITE documentation PDOC00672 [for PROSITE entry PS00859]

GTP cyclohydrolase I signatures


GTP cyclohydrolase I (EC catalyzes the biosynthesis of formic acid and dihydroneopterin triphosphate from GTP. This reaction is the first step in the biosynthesis of tetrahydrofolate in prokaryotes, of tetrahydrobiopterin in vertebrates, and of pteridine-containing pigments in insects.

GTP cyclohydrolase I is a protein of from 190 to 250 amino acid residues. The comparison of the sequence of the enzyme from bacterial and eukaryotic sources shows that the structure of this enzyme has been extremely well conserved throughout evolution [1].

As signature patterns we selected two conserved regions. The first contains a perfectly conserved tetrapeptide which is part of the GTP-binding pocket [2], the second region also contains conserved residues involved in GTP-binding.

Last update:

April 2006 / Pattern revised.

Technical section

PROSITE methods (with tools and information) covered by this documentation:

GTP_CYCLOHYDROL_1_1, PS00859; GTP cyclohydrolase I signature 1  (PATTERN)

GTP_CYCLOHYDROL_1_2, PS00860; GTP cyclohydrolase I signature 2  (PATTERN)


1AuthorsMaier J. Witter K. Gutlich M. Ziegler I. Werner T. Ninnemann H.
TitleHomology cloning of GTP-cyclohydrolase I from various unrelated eukaryotes by reverse-transcription polymerase chain reaction using a general set of degenerate primers.
SourceBiochem. Biophys. Res. Commun. 212:705-711(1995).
PubMed ID7542887

2AuthorsNar H. Huber R. Meining W. Schmid C. Weinkauf S. Bacher A.
TitleAtomic structure of GTP cyclohydrolase I.
SourceStructure 3:459-466(1995).
PubMed ID7663943

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