Immunological characterization of the mitochondrial 2‐oxoglutarate carrier from liver and heart

Abstract
Antibodies have been prepared against the 2‐oxoglutarate transport proteins purified from bovine heart and rat liver mitochondria. The anti‐heart antiserum cross‐reacts with the 2‐oxoglutarate carrier (OGC) from beef, pig, rat and rabbit heart, but not with the OGC from liver of the same animals. Conversely, the anti‐liver antiserum recognizes the carrier protein from liver of all species tested but not from heart. Immunoinactivation of oxoglutarate transport activity by the antibodies is also tissue specific. Peptide maps of purified OGC show structural differences between the carrier from heart and liver of the same animal species. These results indicate the existence of isoforms of the OGC in heart and liver.