Chemolithotrophs fixation

The chemoautotrophic fixation of C02 connected with this activity, only minimally contributes to the carbon cycling in most ecosystems. Notable exceptions to this include the deep-sea hydrothermal vent ecosystems, where the whole vent community is supported by the chemoautotrophic oxidation of reduced sulfur, primarily by Beggiatoa, Thiomi-cropira, and other sulfur oxidizers. In environments other than these, the generation of reduced minerals used in chemolithotrophic production is directly tied to the oxidation of photosynthetically produced organic matter. Therefore, sustainable primary production without solar energy input is unthinkable even in the case of chemolithotrophs. 

Two classes of bacteria are specially adapted for sulfur oxidation (Table 6.1.2) Chemolithotrophic sulfur bacteria which utilize the energy released during oxidation by oxygen for fixation of CO2 into organic matter (e.g. eqn (2))... 

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