Converts guanine to guanosine monophosphate, and hypoxanthine to inosine monophosphate. Transfers the 5- phosphoribosyl group from 5-phosphoribosylpyrophosphate onto the purine. Plays a central role in the generation of purine nucleotides through the purine salvage pathway. Defects in HPRT1 are the cause of Lesch-Nyhan syndrome (LNS). LNS is characterized by complete lack of enzymatic activity that results in hyperuricemia, choreoathetosis, mental retardation, and compulsive self-mutilation. Defects in HPRT1 are the cause of gout HPRT-related (GOUT-HPRT); also known as HPRT-related gout or Kelley-Seegmiller syndrome. Gout is characterized by partial enzyme activity and hyperuricemia. Belongs to the purine/pyrimidine phosphoribosyltransferase family. Note: This description may include information from UniProtKB.
Protein type: EC 184.108.40.206; Nucleotide Metabolism - purine; Xenobiotic Metabolism - drug metabolism - other enzymes; Transferase; Cell development/differentiation
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.