| Modification Notes |
Succinate dehydrogenase is a membrane-bound enzyme complex that localizes to the inner mitochondrial membrane and functions in both the citric acid cycle and the electron transport chain. It is found in several aerobic and anaerobic organisms, including Escherichia coli. Succinate dehydrogenase is a heterotetramer divided into three domains: SDHA, the catalytic domain; SDHB, the electron transfer subunit; SDHC/SDHD, the dimeric membrane anchor that contains ∫-type heme. Mutations in the gene encoding for SDHD are associated with hereditary paraganglioma, possibly through a mechanism that causes a hypoxic response in the cell that leads to tumor formation. SDHD mutation related tumors, which originate in the head and neck, are usually benign. |