” It was presumed that they were flushed there from seafloor vent-associated environments. However we wondered whether the plumes might really be an appropriate environment for some members of the Sulfurimonas group.”.
The Polarstern group led by Prof. Dr. Antje Boetius. Back row, from left: Gunter Wegener, Massimiliano Molari, Mirja Meiners, Rafael Stiens, Antje Boetius, Fabian Schramm, Norbert Rieper. Front row: Andreas Türke, Yann Marcon. Credit: Alfred Wegener Institute/ Stefanie Arndt.
Hard sampling conditions.
Together with associates from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research in Bremerhaven (AWI), and the MARUM Center for Marine Environmental Sciences of Bremen University, Molari hence handled a difficult sampling trip to hydrothermal plumes in the Central Arctic and South Atlantic Ocean.
” We tested plumes in exceptionally remote locations of ultraslow dispersing ridges that were never studied prior to. Collecting hydrothermal plume samples is very complicated, as they are hard to find. Testing becomes much more difficult when the plume lies at depths of more than 2500 meters and listed below Arctic sea ice, or within the stormy zones of the Southern Ocean”, explains Antje Boetius, group leader at the Max Planck Institute for Marine Microbiology and director of the AWI, who was the Chief scientist on the Arctic missions.
Auroras hydrothermal vents at Gakkel Ridge (Central Arctic). A picture of a hydrothermal vent (upper left corner, shown by the red arrow) and chimneys (yellow-orange structures on the right) captured by the undersea electronic camera system OFOS, that made it possible to determine the place of the hydrothermal vents field throughout exploration PS86. Credit: Cruise report.
Onboard of the research vessel Polarstern, the researchers managed to gather samples and within this water studied the structure and metabolic process of germs.
Well-equipped and extensive.
Molari and his colleagues identified a brand-new Sulfurimonas species called USulfurimonas pluma ( the superscript “U” represents uncultivated) living in the cold, oxygen-saturated hydrothermal plumes. Remarkably, this microbe used hydrogen from the plume as an energy source, rather than sulfide. The scientists also investigated the microorganisms genome and found it to be highly reduced, missing genes normal for their family members, but being well-equipped with others to permit them to grow in this vibrant environment.
” We believe that the hydrothermal plume does not just distribute microorganisms from hydrothermal vents, however it might likewise environmentally link the open ocean with seafloor environments. Our phylogenetic analysis suggests that USulfurimonas pluma could have obtained from a hydrothermal vent-associated ancestor, which acquired greater oxygen tolerance and after that spread out across the oceans. However, that remains to be even more examined”, Molari says.
An appearance at genome data from other plumes revealed that USulfurimonas pluma grows in these environments all over the world. “Obviously, they have actually found an eco-friendly specific niche in cold, oxygen-saturated, and hydrogen-rich hydrothermal plumes”, says Molari. “That indicates we need to reassess our ideas on the eco-friendly role of Sulfurimonas in the deep ocean– they may be much more essential than we previously thought.”.
Reference: “A hydrogenotrophic Sulfurimonas is internationally abundant in deep-sea oxygen-saturated hydrothermal plumes” by Massimiliano Molari, Christiane Hassenrueck, Rafael Laso-Pérez, Gunter Wegener, Pierre Offre, Stefano Scilipoti and Antje Boetius, 9 March 2023, Nature Microbiology.DOI: 10.1038/ s41564-023-01342-w.
As the hot water connects with the cold, oxygen-rich seawater nearby, it forms hydrothermal plumes made up of smoke-like metal sulfide particles.
These germs have so far only understood to grow in low-oxygen environments, however gene series had periodically also been found in hydrothermal plumes. A snapshot of a hydrothermal vent (upper left corner, shown by the red arrow) and chimneys (yellow-orange structures on the right) caught by the undersea video camera system OFOS, which made it possible to determine the location of the hydrothermal vents field during expedition PS86.” We think that the hydrothermal plume does not just disperse bacteria from hydrothermal vents, but it may also environmentally link the open ocean with seafloor habitats. “Obviously, they have found an environmental specific niche in cold, oxygen-saturated, and hydrogen-rich hydrothermal plumes”, states Molari.
Enceladus black smoker at the Aurora Vent Field. Credit: HACON cruise 2021, REV Ocean
In the depths of the ocean, along tectonic plate limits, hydrothermal vents give off hot fluids. These fluids lack oxygen and are rich in metals like iron, copper, and manganese, as well as possibly bring sulfides, methane, and hydrogen. As the hot water connects with the cold, oxygen-rich seawater nearby, it forms hydrothermal plumes composed of smoke-like metal sulfide particles.
Increasing hundreds of meters from the seafloor and dispersing thousands of kilometers away from their origin, hydrothermal plumes might appear to be unwelcoming environments. Yet, a study recently published in Nature Microbiology reveals that particular bacteria manage to grow in these seemingly precarious places.
Research study vessel Polarstern on exploration PS86 in the Greenland ice, roughly 4000 m above the Western Vulcanic Zone of Gakkel Ridge. Credit: Alfred Wegener Institute/ Stefanie Arndt
More than simply momentary visitors?
” We took an in-depth take a look at germs of the genus Sulfurimonas”, says first author Massimiliano Molari from limit Planck Institute for Marine Microbiology in Bremen, Germany. These bacteria have up until now just understood to grow in low-oxygen environments, but gene series had periodically also been found in hydrothermal plumes. As their name suggests, they are understood to use energy from sulfide.