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orotic acid

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

15 compounds within 3 steps: 2 in 1, 4 in 2, 9 in 3

Does it reach a compound?

One step

CHEBI:15842Reach from here →
1. Orotidine-5'-phosphate:diphosphate phospho-alpha-D-ribosyl-transferase
Catalysed by UMPScytosol
(S)-dihydroorotateReach from here →
1. (S)-dihydroorotate:NAD+ oxidoreductase
Catalysed by DHODHcytosol

Two steps

N-carbamoyl-L-aspartic acidReach from here →
1. (S)-dihydroorotate:NAD+ oxidoreductase
2. (S)-dihydroorotate amidohydrolase
Catalysed by DHODH, CADcytosol
a quinolReach from here →
1. (S)-dihydroorotate:NAD+ oxidoreductase
2. (S)-dihydroorotate + a quinone = orotate + a quinol
Catalysed by DHODHcytosol
orotateReach from here →

Three steps

a quinoneReach from here →
Catalysed by DHODH, CYC1, UQCRFS1cytosol, outer side of the membraneOne of 7 routes
a carboxylateReach from here →
Catalysed by

(S)-dihydroorotate:NAD+ oxidoreductase

(S)-dihydroorotate + a quinone = orotate + a quinol

Catalysed by DHODHcytosol

N-carbamoyl-L-aspartateReach from here →

(S)-dihydroorotate:NAD+ oxidoreductase
(S)-dihydroorotate + H2O = N-carbamoyl-L-aspartate + H(+)

Catalysed by DHODH, CADcytosol

cytosol, inner side of the membrane, outer side of the membrane

One of 2 routes

L-aspartateReach from here →

(S)-dihydroorotate:NAD+ oxidoreductase
(S)-dihydroorotate amidohydrolase
carbamoyl-phosphate:L-aspartate carbamoyltransferase

Catalysed by DHODH, CADcytosolOne of 2 routes

nicotinateReach from here →

(S)-dihydroorotate:NAD+ oxidoreductase
(S)-dihydroorotate + a quinone = orotate + a quinol
orotate(out) + nicotinate(in) = orotate(in) + nicotinate(out)

Catalysed by DHODH, SLC22A12cytosol, inner side of the membrane, outer side of the membraneOne of 2 routes

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

(S)-dihydroorotate:NAD+ oxidoreductase
(S)-dihydroorotate + a quinone = orotate + a quinol
1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone + H(+) = beta-nicotinamide D-riboside + a quinol

Catalysed by DHODH, NQO2cytosol

orotidine 5'-phosphateReach from here →

(S)-dihydroorotate:NAD+ oxidoreductase
(S)-dihydroorotate + a quinone = orotate + a quinol
orotidine 5'-phosphate + diphosphate = orotate + 5-phospho-alpha-D-ribose 1-diphosphate

Catalysed by DHODH, UMPScytosol

carbamoyl phosphateReach from here →

(S)-dihydroorotate:NAD+ oxidoreductase
(S)-dihydroorotate amidohydrolase
carbamoyl-phosphate:L-aspartate carbamoyltransferase

Catalysed by DHODH, CADcytosolOne of 2 routes

trans-4-hydroxy-L-prolineReach from here →

(S)-dihydroorotate:NAD+ oxidoreductase
(S)-dihydroorotate + a quinone = orotate + a quinol
trans-4-hydroxy-L-proline + a quinone = (3R,5S)-1-pyrroline-3-hydroxy-5-carboxylate + a quinol + H(+)

Catalysed by DHODH, PRODH2cytosol

L-prolineReach from here →

(S)-dihydroorotate:NAD+ oxidoreductase
(S)-dihydroorotate + a quinone = orotate + a quinol
L-proline + a quinone = (S)-1-pyrroline-5-carboxylate + a quinol + H(+)

Catalysed by DHODH, PRODH, PRODH2cytosol