5-phospho-alpha-D-ribose 1-diphosphate

1. Nicotinate-nucleotide:pyrophosphate phosphoribosyltransferase (carboxylating)

Catalysed by QPRTcytosolOne of 2 routes

1. Orotidine-5'-phosphate:diphosphate phospho-alpha-D-ribosyl-transferase

Catalysed by UMPScytosol

1. nicotinamide-D-ribonucleotide:diphosphate phospho-alpha-D-ribosyltransferase

Catalysed by NAMPTcytosolOne of 2 routes

1. IMP:diphosphate phospho-D-ribosyltransferase

Catalysed by HPRT1cytosol

1. XMP:pyrophosphate phosphoribosyltransferase

Catalysed by HPRT1cytosol

1. nicotinate beta-D-ribonucleotide + CO2 + diphosphate = quinolinate + 5-phospho-alpha-D-ribose 1-diphosphate + 2 H(+)

Catalysed by QPRTOne of 2 routes

1. orotidine 5'-phosphate + diphosphate = orotate + 5-phospho-alpha-D-ribose 1-diphosphate

Catalysed by UMPS

1. IMP + diphosphate = hypoxanthine + 5-phospho-alpha-D-ribose 1-diphosphate

Catalysed by HPRT1

1. phosphoribosyl pyrophosphate amidotransferase (glutamine)

Catalysed by PPATcytosolOne of 2 routes

1. 5-phospho-alpha-D-ribose 1-diphosphate + H2O = alpha-D-ribose 1,5-bisphosphate + phosphate + H(+)

Catalysed by NUDT4

1. phosphoribosyl pyrophosphate amidotransferase (glutamine)
2. 5-phospho-beta-D-ribosylamine + glycine + ATP = N(1)-(5-phospho-beta-D-ribosyl)glycinamide + ADP + phosphate + H(+)

Catalysed by PPAT, GARTcytosol

1. nicotinamide-D-ribonucleotide:diphosphate phospho-alpha-D-ribosyltransferase
2. 5'-nucleotidase (nicotinamide D-ribonucleotide)

Catalysed by NAMPT, ACP3, NT5E, NT5C and 4 morecytosolOne of 2 routes

1. nicotinamide-D-ribonucleotide:diphosphate phospho-alpha-D-ribosyltransferase
2. 5'-nucleotidase (nicotinamide D-ribonucleotide)
3. 1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol

Catalysed by NAMPT, ACP3, NT5E, NT5C and 5 morecytosol

1. phosphoribosyl pyrophosphate amidotransferase (glutamine)
2. 5-phospho-beta-D-ribosylamine + glycine + ATP = N(1)-(5-phospho-beta-D-ribosyl)glycinamide + ADP + phosphate + H(+)
3. N(1)-(5-phospho-beta-D-ribosyl)glycinamide + (6R)-10-formyltetrahydrofolate = N(2)-formyl-N(1)-(5-phospho-beta-D-ribosyl)glycinamide + (6S)-5,6,7,8-tetrahydrofolate + H(+)