Q26997 · HGXR_TOXGO

  • Protein
    Hypoxanthine-guanine-xanthine phosphoribosyltransferase
  • Gene
    HPRT
  • Status
    UniProtKB reviewed (Swiss-Prot)
  • Amino acids
  • Protein existence
    Evidence at protein level
  • Annotation score
    5/5

Function

function

Catalyzes the transfer of a ribosyl phosphate group from 5-phosphoribose 1-diphosphate to the N9 of hypoxanthine, guanine or xanthine, leading to IMP, GMP and XMP, respectively. Plays a central role in the generation of purine nucleotides through the purine salvage pathway.

Catalytic activity

Cofactor

Mg2+ (UniProtKB | Rhea| CHEBI:18420 )

Note: Binds 2 magnesium ions per subunit. The magnesium ions are essentially bound to the substrate and have few direct interactions with the protein.

Pathway

Purine metabolism; GMP biosynthesis via salvage pathway; GMP from guanine: step 1/1.
Purine metabolism; IMP biosynthesis via salvage pathway; IMP from hypoxanthine: step 1/1.
Purine metabolism; XMP biosynthesis via salvage pathway; XMP from xanthine: step 1/1.

Features

Showing features for binding site, active site.

TypeIDPosition(s)Description
Binding site79GMP (UniProtKB | ChEBI)
Binding site146-154GMP (UniProtKB | ChEBI)
Active site150Proton acceptor
Binding site178GMP (UniProtKB | ChEBI)
Binding site199-200GMP (UniProtKB | ChEBI)
Binding site206GMP (UniProtKB | ChEBI)
Binding site206Mg2+ (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentcytoplasm
Molecular Functionguanine phosphoribosyltransferase activity
Molecular Functionhypoxanthine phosphoribosyltransferase activity
Molecular Functionmetal ion binding
Molecular Functionnucleotide binding
Molecular Functionxanthine phosphoribosyltransferase activity
Biological ProcessGMP salvage
Biological ProcessIMP salvage
Biological Processpurine ribonucleoside salvage
Biological ProcessXMP salvage

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Hypoxanthine-guanine-xanthine phosphoribosyltransferase
  • EC number
  • Short names
    HGPRT; HGXPRT; HGXPRTase

Gene names

    • Name
      HPRT

Organism names

  • Taxonomic identifier
  • Strain
    • RH
  • Taxonomic lineage
    Eukaryota > Sar > Alveolata > Apicomplexa > Conoidasida > Coccidia > Eucoccidiorida > Eimeriorina > Sarcocystidae > Toxoplasma

Accessions

  • Primary accession
    Q26997

Organism-specific databases

Subcellular Location

Keywords

Phenotypes & Variants

Features

Showing features for mutagenesis.

TypeIDPosition(s)Description
Mutagenesis150Strongly reduced catalytic activity.

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00001395991-230Hypoxanthine-guanine-xanthine phosphoribosyltransferase

Interaction

Subunit

Homodimer at low ionic strength and homotetramer at high ionic strength.

Family & Domains

Sequence similarities

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    230
  • Mass (Da)
    26,386
  • Last updated
    1996-11-01 v1
  • Checksum
    C3784254EF96361D
MASKPIEDYGKGKGRIEPMYIPDNTFYNADDFLVPPHCKPYIDKILLPGGLVKDRVEKLAYDIHRTYFGEELHIICILKGSRGFFNLLIDYLATIQKYSGRESSVPPFFEHYVRLKSYQNDNSTGQLTVLSDDLSIFRDKHVLIVEDIVDTGFTLTEFGERLKAVGPKSMRIATLVEKRTDRSNSLKGDFVGFSIEDVWIVGCCYDFNEMFRDFDHVAVLSDAARKKFEK

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
U09219
EMBL· GenBank· DDBJ
AAA57068.1
EMBL· GenBank· DDBJ
mRNA

Similar Proteins

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care. Our staff consists of biologists and biochemists that are not trained to give medical advice.
We'd like to inform you that we have updated our Privacy Notice to comply with Europe’s new General Data Protection Regulation (GDPR) that applies since 25 May 2018.
FeedbackHelp