Enzymes and pathways found in various manifestations of mitochondria

Proteins sharing more sequence similarity to eubacterial than to archaebacterial homologues are shaded blue; those with converse similarity pattern are shaded red; those whose presence is based only on biochemical evidence are shaded grey; those lacking clearly homologous counterparts in prokaryotes are shaded green. (A) Schematic summary of salient biochemical functions in mitochondria, including some anaerobic forms. (B) Schematic summary of salient biochemical functions in hydrogenosomes. (C) Schematic summary of available findings for mitosomes and 'remnant' mitochondria. The asterisk next to the Trachipleistophora and Cryptosporidium mitosomes denotes that these organisms are not anaerobes in the sense that they do not inhabit O₂-poor niches, but that their ATP supply is apparently O₂-independent. UQ, ubiquinone; CI, mitochondrial complex I (and II, III and IV, respectively); NAD, nicotinamide adenine dinucleotide; MCF, mitochondrial carrier family protein transporting ADP and ATP; STK, succinate thiokinase; PFO, pyruvate:ferredoxin oxidoreductase; PDH, pyruvate dehydrogenase; CoA, coenzyme A; Fd, ferredoxin; HDR, iron-only hydrogenase; PFL, pyruvate:formate lyase; ASC, acetate-succinate CoA transferase; ADHE, bi-functional alcohol acetaldehyde dehydrogenase; FRD, fumarate reductase; RQ, rhodoquinone; Hsp, heat shock protein; IscU, iron–sulphur cluster assembly scaffold protein; IscS; cysteine desulphurase; ACS (ADP), acetyl-CoA synthase (ADP-forming).