oxalosuccinate synthetase; carboxylating factor for ICDH (incorrect); CFI; OGC
A biotin-containing enzyme that requires Mg2+ for activity. It was originally thought  that this enzyme was a promoting factor for the carboxylation of 2-oxoglutarate by EC 18.104.22.168, isocitrate dehydrogenase (NAD+), but this has since been disproved . The product of the reaction is unstable and is quickly converted into isocitrate by the action of EC 22.214.171.124 .
Aoshima, M., Ishii, M. and Igarashi, Y. A novel biotin protein required for reductive carboxylation of 2-oxoglutarate by isocitrate dehydrogenase in Hydrogenobacter thermophilus TK-6. Mol. Microbiol.51 (2004) 791–798. [PMID: 14731279]
Aoshima, M. and Igarashi, Y. A novel oxalosuccinate-forming enzyme involved in the reductive carboxylation of 2-oxoglutarate in Hydrogenobacter thermophilus TK-6. Mol. Microbiol.62 (2006) 748–759. [PMID: 17076668]