scientific journey 2016 revealed an underground habitat where microbes were found living in temperatures close to 250 degrees Fahrenheit. now A follow-up study reveals How this wonderful microbial community manages to beat the heat.
High metabolic rates make life possible for microorganisms that live in sediments buried deep on the sea floor, researchers said. للبحث Published in Nature Communication. The study, led by marine biologist Tina Triod of the University of California, Los Angeles, has shed new light on subterranean microbes, showing that some are surprisingly energetic and able to thrive in deep, warm conditions.
“We have always found that the microbes in the deep biosphere are a very slow-moving community that is slowly nibbling at the last remnants of buried organic matter millions of years old. But the deep biosphere is full of surprises,Bo Barker Jorgensen, a microbiologist at Aarhus University in Denmark, said: In a press release from the University of California. “Finding life thriving with high metabolic rates at these high temperatures on the deep sea floor fuels our imaginations about how life might have evolved or survived in similar environments on extraterrestrial planetary bodies.”
In an email, Virginia Edgecombe, a geologist at Woods Hole Oceanographic Institution who was not involved in the new study, said she was excited about the He also states that “we cannot assume that microbial activities are insignificant merely because of depth under the sea floor or extreme temperatures”, particularly when “sufficient sources of carbon and energy are available”.
In this case, the necessary sources of carbon and energy are found in the Nankai Trough subduction zone off the coast of Japan. Seven years ago, a scientific expedition led by the same team drilled 3,930 feet (1,200 meters) below the sea floor, to bring back samples of marine sediment and evidence of highly sensitive microbes. that they He did this to study the temperature limit of the deep underwater biosphere and the potential for life to exist in this extreme habitat. Incredibly, hmm You find A small community of microbes that seemed to thrive despite temperatures reaching 250°F (120°C). It was not entirely clear to the researchers How this was possible prompted further study.
For the new investigation, Treude and colleagues conducted radioactive tracking experiments to measure the metabolic rates of microbes, which they did under highly sterile conditions to avoid contamination. it wasn’t easy, Given the low population density of microbes; Less than 500 cells were present in each cubic centimeter of sediment. The team also made special arrangements forIt is certain that the metabolic rates observed in the laboratory were the same as in the natural environment of the microbes.
This work led to the discovery of the rapid metabolism of microorganisms, which, according to the researchers, allows them to survive in such harsh conditions.. Scientists are of the opinion that higher metabolic rates are essential, Allowing microbes to repair heat damaged cells.
“The energy required to repair thermal damage to cellular components increases sharply with temperature, and it is likely that most of this energy is required to counteract the ongoing change in amino acids and loss of protein function,” Treude said.
At the same time, microbes They have great access to nutrients that are provided by heating organic matter, especially hydrogen and acetate, from water flowing through the marine environment. sediment;
Edgecombe said the new observations “may seem counterintuitive to many, that is, cells that live near the thermal limits of life there, and very deep under the sea floor, where we would expect them to hardly live, are actually very active.” The activity rate is for a very interesting reason: “To be able to provide enough energy to repair the damage done to the thermal cells so that they can survive,” she added.
In an email, Jennifer Biddle, an assistant professor at the University of Delaware who is not affiliated with research, said the new work “looks good” and “compliments well.” Pre-existing work Changes in microbial communities and increased cell division appearion With increasing sediment temperature. One of the arguments made in the new paper is that cells only start once they have already been buried – a finding that correlates with the latest للبحث It was co-authored by Biddle explaining that “once the cells find their ‘happy place’ in the basement, they have a lot of strength to grow,” she said..
HaddBiddle said Researchers describe bacterial activity corn He did not name or identify the microbes involved. “It would be good to know who’s there,” she said. So we can better estimate how fast they can go,” he said, adding that it would also be good “to grow some of these lines underground to test their thermal ranges and how they might adapt to this environment.” ”
Interestingly, these underwater microbes are approaching the thermal limits of life as we know it, but some scientists believe that microbes may have to survive Even in the warmest environments. Looks like we should dig a little deeper next time, because it’s more extreme Microbes may still be waiting to be found.
next: Ancient microbes come back to life after 100 million years under the sea floor.