Click For Photo: https://scx2.b-cdn.net/gfx/news/hires/2019/3-deepseabacte.jpg
In the deep sea, far away from the light of the sun, organisms use chemical energy to fix carbon. At hydrothermal vents—where hot, mineral-rich water gushes out of towering chimneys called black smokers—vibrant ecosystems are fueled by chemical energy in the vent waters. Mussels thrive in this seemingly hostile environment, nourished by symbiotic bacteria inside their gills. The bacteria convert chemicals from the vents, which the animals cannot use, into tasty food for their mussel hosts. Now an international group of scientists led by Nicole Dubilier from the Max Planck Institute of Marine Microbiology in Bremen and Jillian Petersen, now at the University of Vienna, reports in ISME Journal that carbon fixation in the deep sea is more diverse than previously thought.
It has long been known that deep-sea Bathymodiolus mussels, distant relatives of the edible, shallow-water blue mussel, harbor symbionts inside their gills. In 2016, Adrien Assié carried out his Ph.D. at the Max Planck Institute for Marine Microbiology and discovered symbiotic bacteria living between the mussel's gills, calling them Thiobarba. Adrien's further studies reveal that these bacteria not only belong to a family not yet known, but also feed in an unexpected way. "Thiobarba fixes carbon using the Calvin cycle," explains Nikolaus Leisch, shared-first author of the study. "It is the first of this bacterial group to use this pathway for carbon fixation." Usually this group uses a pathway known as the reverse TCA-cycle, which is much more energy efficient, to fix carbon. However, it does not work well in the presence of oxygen, which...
Wake Up To Breaking News!