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nicotinamide

362,296 routes · scope human · up to 3 steps · built 5 October 2026 · Reactions · API

Inferred

Every route here is a hypothesis drawn from reference reactions (Rhea and Human-GEM), not a finding. Currency species such as water, ATP and NAD(H) never form a step. Evidence key

27 compounds within 3 steps: 4 in 1, 5 in 2, 18 in 3

Does it reach a compound?

One step

beta-nicotinamide D-ribosideReach from here →
1. purine nucleoside phosphorylase (nicotinamide)
Catalysed by PNPcytosol
NMN zwitterionReach from here →
1. nicotinamide-D-ribonucleotide:diphosphate phospho-alpha-D-ribosyltransferase
Catalysed by NAMPTcytosolOne of 2 routes
1-methylnicotinamideReach from here →
1. S-Adenosyl-L-methionine:nicotinamide N-methyltransferase
Catalysed by NNMTcytosolOne of 2 routes
alpha-NAD(+)Reach from here →
1. alpha-NAD(+) + H2O = ADP-D-ribose + nicotinamide + H(+)
Catalysed by MACROD2, ADPRH, MACROD1, ADPRS and 1 more

Two steps

a quinoneReach from here →
1. purine nucleoside phosphorylase (nicotinamide)
2. 1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol
Catalysed by PNP, NQO2cytosol
nicotinic acid D-ribonucleotideReach from here →
1. nicotinamide-D-ribonucleotide:diphosphate phospho-alpha-D-ribosyltransferase
2. nicotinamide-D-ribonucleotide amidohydrolase
Catalysed by NAMPTcytosol
D-ribose 1-phosphateReach from here →

Three steps

a 1,4-benzosemiquinoneReach from here →
Catalysed by PNP, NQO2, CRYZ, TP53I3 and 2 morecytosol
adenosineReach from here →

purine nucleoside phosphorylase (nicotinamide)

purine nucleoside phosphorylase (nicotinamide)

Catalysed by PNPcytosol

1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamideReach from here →

purine nucleoside phosphorylase (nicotinamide)
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol

Catalysed by PNP, NQO2cytosol

ADP-D-riboseReach from here →

alpha-NAD(+) + H2O = ADP-D-ribose + nicotinamide + H(+)
H2O[n] + alpha-NAD(+)[n] = ADP-ribose[n] + H+[n] + nicotinamide[n]

Catalysed by MACROD2, ADPRH, MACROD1, ADPRS and 1 morenucleusOne of 2 routes

Catalysed by PNP

cytosol

uridineReach from here →

purine nucleoside phosphorylase (nicotinamide)
purine nucleoside phosphorylase (nicotinamide)
uridine:phosphate alpha-D-ribosyltransferase

Catalysed by PNP, UPP2, UPP1cytosol

guanosineReach from here →

purine nucleoside phosphorylase (nicotinamide)
purine nucleoside phosphorylase (nicotinamide)
guanosine:phosphate alpha-D-ribosyltransferase

Catalysed by PNPcytosol

(S)-1-pyrroline-5-carboxylateReach from here →

purine nucleoside phosphorylase (nicotinamide)
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol
L-proline + a quinone = (S)-1-pyrroline-5-carboxylate + a quinol + H(+)

Catalysed by PNP, NQO2, PRODH, PRODH2cytosol

enol-oxaloacetateReach from here →

purine nucleoside phosphorylase (nicotinamide)
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol
(R)-malate + a quinone = enol-oxaloacetate + a quinol

Catalysed by PNP, NQO2, SDHB, SDHAcytosolOne of 2 routes

inosineReach from here →

purine nucleoside phosphorylase (nicotinamide)
purine nucleoside phosphorylase (nicotinamide)
inosine:phosphate alpha-D-ribosyltransferase

Catalysed by PNPcytosol

CHEBI:17797Reach from here →

purine nucleoside phosphorylase (nicotinamide)
purine nucleoside phosphorylase (nicotinamide)
D-Ribose 1,5-phosphomutase

Catalysed by PNP, PGM2cytosolOne of 3 routes

fumaric acidReach from here →

purine nucleoside phosphorylase (nicotinamide)
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol
a quinone + succinate = fumarate + a quinol

Catalysed by PNP, NQO2, SDHBcytosol

xanthosineReach from here →

purine nucleoside phosphorylase (nicotinamide)
purine nucleoside phosphorylase (nicotinamide)
xanthosine:orthophosphate ribosyltransferase

Catalysed by PNPcytosol

a quinolReach from here →

purine nucleoside phosphorylase (nicotinamide)
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol
a quinol + 2 Fe(III)-[cytochrome c](out) = a quinone + 2 Fe(II)-[cytochrome c](out) + 2 H(+)(out)

Catalysed by PNP, NQO2, CYC1, UQCRFS1cytosol, outer side of the membraneOne of 13 routes

orotateReach from here →

purine nucleoside phosphorylase (nicotinamide)
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol
(S)-dihydroorotate + a quinone = orotate + a quinol

Catalysed by PNP, NQO2, DHODHcytosol

dihydroxyacetone phosphateReach from here →

purine nucleoside phosphorylase (nicotinamide)
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol
a quinone + sn-glycerol 3-phosphate = dihydroxyacetone phosphate + a quinol

Catalysed by PNP, NQO2, GPD2cytosol

deamido-NAD(+)Reach from here →

nicotinamide-D-ribonucleotide:diphosphate phospho-alpha-D-ribosyltransferase
nicotinamide-D-ribonucleotide amidohydrolase
Nicotinate-Nucleotide Adenylyltransferase, Mitochondrial

Catalysed by NAMPT, NMNAT3cytosol, mitochondrial matrixOne of 3 routes

beta-D-ribosylnicotinateReach from here →

nicotinamide-D-ribonucleotide:diphosphate phospho-alpha-D-ribosyltransferase
nicotinamide-D-ribonucleotide amidohydrolase
nicotinate D-ribonucleotide phosphohydrolase

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

S-sulfanylglutathioneReach from here →

purine nucleoside phosphorylase (nicotinamide)
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol
a quinone + hydrogen sulfide + glutathione + H(+) = S-sulfanylglutathione + a quinol

Catalysed by PNP, NQO2, SQORcytosol

(3R,5S)-1-pyrroline-3-hydroxy-5-carboxylateReach from here →

purine nucleoside phosphorylase (nicotinamide)
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol
trans-4-hydroxy-L-proline + a quinone = (3R,5S)-1-pyrroline-3-hydroxy-5-carboxylate + a quinol + H(+)

Catalysed by PNP, NQO2, PRODH2cytosol

D-ribose 5-phosphateReach from here →

alpha-NAD(+) + H2O = ADP-D-ribose + nicotinamide + H(+)
H2O[n] + alpha-NAD(+)[n] = ADP-ribose[n] + H+[n] + nicotinamide[n]
ADP-D-ribose + H2O = D-ribose 5-phosphate + AMP + 2 H(+)

Catalysed by MACROD2, ADPRH, MACROD1, ADPRS and 5 morenucleusOne of 2 routes