ribose-phosphate pyrophosphokinase 1; PPribP; phosphoribosyl pyrophosphate synthase 1; PRS-1 (PRPS1)

Function

• catalyzes synthesis of phosphoribosylpyrophosphate (PRPP), essential for nucleotide synthesis
• activated by Mg+2 & inorganic phosphate
• metabolic intermediate biosynthesis; 5-phospho-alpha-D-ribose 1-diphosphate biosynthesis; 5-phospho-alpha-D-ribose 1-diphosphate from D-ribose 5-phosphate (route I): step 1/1

ATP + D-ribose 5-phosphate = AMP + 5-phospho-alpha-D-ribose 1-diphosphate

Cofactor: Mg+2

Structure

• homodimer
• the active form is probably an hexamer composed of 3 homodimers
• belongs to the ribose-phosphate pyrophosphokinase family

Pathology

• defects in PRPS1 are the cause of
  • phosphoribosylpyrophosphate synthetase superactivity
  • Charcot-Marie-Tooth disease type 5
  • ARTS syndrome
  • X-linked deafness 1

More general terms

• phosphoribosyl pyrophosphate synthetase

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=5631
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:5631
• OMIM: https://mirror.omim.org/entry/300661
• OMIM: https://mirror.omim.org/entry/301835
• OMIM: https://mirror.omim.org/entry/304500
• OMIM: https://mirror.omim.org/entry/311070
• OMIM: https://mirror.omim.org/entry/311850
• UniProt: http://www.uniprot.org/uniprot/P60891.html