Mitochondrial ornithine-citrulline antiporter (Probable) (PubMed:12807890, PubMed:22262851). Catalyzes the exchange between cytosolic ornithine and mitochondrial citrulline plus an H(+), the proton compensates the positive charge of ornithine thus leading to an electroneutral transport. Plays a crucial role in the urea cycle, by connecting the cytosolic and the intramitochondrial reactions of the urea cycle (Probable) (PubMed:12807890, PubMed:22262851). Lysine and arginine are also transported by the antiport mechanism (Probable) (PubMed:12807890). In addition, catalyzes an electroneutral exchange of ornithine or lysine for H(+), a reaction driven by the pH gradient across the inner membrane (By similarity). {ECO:0000250|UniProtKB:A0A0G2K309, ECO:0000269|PubMed:12807890, ECO:0000269|PubMed:22262851, ECO:0000305|PubMed:10369256, ECO:0000305|PubMed:19242930, ECO:0000305|PubMed:24721342}. This is the function of Ensembl gene identifier ENSG00000102743 (SLC25A15, solute carrier family 25 member 15).