(
2006-11-14)
Markert, Stephanie; Arndt, Cordelia; Felbeck, Horst; Becher, Dorte; Sievert, Stefan M.; Hugler, Michael; Albrecht, Dirk; Robidart, Julie; Bench, Shellie; Feldman, Robert A.; Hecker, Michael; Schweder, Thomas
The bacterial endosymbiont of the deep-sea tube worm Riftia pachyptila has
never been successfully cultivated outside its host. In the absence of cultivation data we
have taken a proteomic approach based on the metagenome sequence to study the
metabolism of this peculiar microorganism in detail. As one result, we found that three
major sulfide oxidation proteins constitute ~12% of the total cytosolic proteome,
highlighting the essential role of these enzymes for the symbiont’s energy metabolism.
Unexpectedly, the symbiont uses the reductive tricarboxylic acid (TCA) cycle in addition
to the previously identified Calvin cycle for CO2 fixation.
