 "Aquifex" respiration and fixation pathways use similar pathways to that of other autotrophic bacteria.Carbon fixation is done using the reductive TCA cycle and forms acetyl-CoA as well as many other bio-synthetic materials.Many bacterium use products from the TCA cycle in the pentose-phosphate pathway and Entner-Doudoroff pathway or Embden-Meyerhof-Parnas pathway however, many enzymes that are necessary for these gluconeogenic processes have not been identified in "A. aeolicus" suggesting a different pathway might be used.