Unknown enzyme hydrogenates HPP

Stable Identifier
R-HSA-9971565
Type
Reaction [transition]
Species
Homo sapiens
Compartment
cytosol
ReviewStatus
5/5
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Unknown enzyme hydrogenates HPP
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An unknown NAD+-dependent dehydrogenase catalyzes the hydrogenation of p-hydroxyphenylpyruvate (HPP) to p-hydroxyphenyllactate (HPL). Normally, production of HPL is a minor side reaction of tyrosine catabolism (Bush et al., 2020), but is enhanced in type 3 tyrosinemia caused by 4-hydroxyphenylpyruvate dioxygenase (HPD) deficiency (reviewed in Russo et al., 2001). Candidates for the catalyzing enzyme(s) are malate or lactate dehydrogenases (Friedrich et al., 1987).
Literature References
PubMed ID Title Journal Year
32271169 Gut-derived uremic toxin handling in vivo requires OAT-mediated tubular secretion in chronic kidney disease

Bush, KT, Singh, P, Nigam, SK

JCI Insight 2020
2449162 The reduction of aromatic alpha-keto acids by cytoplasmic malate dehydrogenase and lactate dehydrogenase

Friedrich, CA, Morizot, DC, Siciliano, MJ, Ferrell, RE

Biochem Genet 1987
11370259 Tyrosinemia: a review

Russo, PA, Mitchell, GA, Tanguay, RM

Pediatr Dev Pathol 2001
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Catalyst Activity

L-2-hydroxycarboxylate dehydrogenase (NAD+) activity of Unknown enzyme [cytosol]

Physical Entity
Unknown enzyme [cytosol] (Homo sapiens)
Activity
L-2-hydroxycarboxylate dehydrogenase (NAD+) activity (GO:0102443)
Cross References
RHEA
Authored
Stephan, R  (2025-11-07)
Reviewed
D'Eustachio, P  (2026-02-10)
Created
Stephan, R  (2025-11-07)
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