ornithine (cytosolic) + citrulline (mitochondrial) => ornithine (mitochondrial) + citrulline (cytosolic)

Stable Identifier
Reaction [transition]
Homo sapiens
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The mitochondrial ornithine transporters SLC25A15 and SLC25A2 mediate the exchange of cytosolic ornithine for citrulline from the mitochondrial matrix. SLC25A15 was the first protein shown to have this function, identified because mutations in the protein are associated with elevated levels of ammonia, ornithine, and citrulline in affected individuals (Camacho et al. 1999). The second transporter, SLC25A2, identified later, is also expressed in normal cells and their apparently partly redundant function may explain the relatively mild symptoms associated with SLC25A15 deficiency compared to other defects of the urea cycle (Fiermonte et al. 2003).

Literature References
PubMed ID Title Journal Year
10369256 Hyperornithinaemia-hyperammonaemia-homocitrullinuria syndrome is caused by mutations in a gene encoding a mitochondrial ornithine transporter.

Goodman, BK, Camacho, JA, Obie, C, Biery, B, Valle, D, Lambert, M, Mitchell, GA, Steel, G, Casey, R, Hu, CA, Almashanu, S

Nat Genet 1999
12807890 The mitochondrial ornithine transporter. Bacterial expression, reconstitution, functional characterization, and tissue distribution of two human isoforms

Fiermonte, G, Dolce, V, Walker, JE, Palmieri, F, David, L, Dionisi-Vici, C, Santorelli, FM

J Biol Chem 2003
12948741 Cloning and characterization of human ORNT2: a second mitochondrial ornithine transporter that can rescue a defective ORNT1 in patients with the hyperornithinemia-hyperammonemia-homocitrullinuria syndrome, a urea cycle disorder

Andrade, D, Rioseco-Camacho, N, Camacho, JA, Kong, J, Porter, J

Mol Genet Metab 2003
Catalyst Activity

L-ornithine transmembrane transporter activity of Mitochondrial ornithine transporters [mitochondrial inner membrane]

Orthologous Events
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