User:Mattdwill97/Hydrogen sulfide chemosynthesis

Lead
=== Hydrogen sulfide chemosynthesis is a form of chemosynthesis which uses hydrogen sulfide. It is common in hydrothermal vent microbial communities Due to the lack of light in these environments this is predominant over photosynthesis ===

Article body :
Giant tube worms use bacteria in their trophosome to fix carbon dioxide (using hydrogen sulfide as their energy source) and produce sugars and amino acids. Some reactions produce sulfur:


 * hydrogen sulfide chemosynthesis:
 * 18H2S + 6CO2 + 3O2 → C6H12O6 (carbohydrate) + 12H2O + 18S

In the above process, hydrogen sulfide serves as a source of electrons for the reaction. Instead of releasing oxygen gas while fixing carbon dioxide as in photosynthesis, hydrogen sulfide chemosynthesis produces solid globules of sulfur in the process. In bacteria capable of chemoautotrophy (a form a chemosynthesis), such as purple sulfur bacteria, yellow globules of sulfur are present and visible in the cytoplasm.

Mechanism of Action

In different deep sea environments, different organisms have been observed to have the ability to oxidize reduced compounds such as hydrogen sulfide (Breusing). Oxidation is the loss of electrons in a chemical reaction. Franco and Vargas (2018). Most chemosynthetic bacteria form symbiotic associations with other small eukaryotes (Sogin et.al., 2020). The electrons that are released from hydrogen sulfide will provide the energy to sustain a proton gradient across the bacterial cytoplasmic membrane. This movement of protons will eventually result in the production of adenosine triphosphate. The amount of energy derived from the process is also dependent on the type of final electron acceptor. (Teske, 2009).

Examples of Chemosynthetic Organisms (using H2S as electron donor)

Across the world researchers have observed different organisms in various locations capable of carrying out the process. Yang and colleagues in 2011 surveyed five Yellowstone thermal springs of varying depths. Differences in microbial distribution coincided with temperature as Sulfurihydrogenibiom was found at higher temperatures while Thiovirga inhabited cooler waters. Miyazaki et.al., in 2020 also found that endosymbionts containing campylobacter species and a gastropod from the genus Alviniconcha oxidise hydogen sulfide in the Indian Ocean.

References (For the New Sections put on)
Breusing, C., Mitchell, J., Delaney, J. et al. Physiological dynamics of chemosynthetic symbionts in hydrothermal vent snails. ISME J 14, 2568–2579 (2020). https://doi.org/10.1038/s41396-020-0707-2

Kalenitchenko, D., Le Bris, N., Dadaglio, L., Peru, E., Besserer, A., & Galand, P. E. (2018). Bacteria alone establish the chemical basis of the wood-fall chemosynthetic ecosystem in the deep-sea. The ISME journal, 12(2), 367–379. https://doi.org/10.1038/ismej.2017.163

Miyazaki, J., Ikuta, T., Watsuji, T. O., Abe, M., Yamamoto, M., Nakagawa, S., Takaki, Y., Nakamura, K., & Takai, K. (2020). Dual energy metabolism of the Campylobacterota endosymbiont in the chemosynthetic snail Alviniconcha marisindica. The ISME journal, 14(5), 1273–1289. https://doi.org/10.1038/s41396-020-0605-7, E. M., Leisch, N., & Dubilier, N. (2020). Chemosynthetic symbioses. Current biology : CB, 30(19), R1137–R1142. https://doi.org/10.1016/j.cub.2020.07.050

Teske, A. (2009). “Deep-sea gydrothermal vents,” in Encyclopedia of microbiology. ed. M. Schaechter. Third ed (Oxford: Academic Press), 80–90.

Yang, T., Lyons, S., Aguilar, C., Cuhel, R., & Teske, A. (2011). Microbial communities and chemosynthesis in yellowstone lake sublacustrine hydrothermal vent waters. Frontiers in microbiology, 2, 130. https://doi.org/10.3389/fmicb.2011.00130