Scientists know more about the depths of space than about the deepest parts of our planet's oceans.
The Deep Challenger is located in the heart of the Pacific Ocean, more than 200 km north of Guam and less than 11,000 meters from the ocean.
The deepest part of the infamous Mariana Trench – a 43-km-wide crescent canyon that crosses 2,500 km of ocean at the edge of two tectonic plates – the Challenger Deep is home to a unique ecosystem of creatures and microorganisms . (It's also the final resting place for thousands of synthetic microplastic pollutants.)
Read more: Tiny plastic particles pollute the deepest point of the ocean
According to a new study published in the journal Microbiome, a group of bacteria trawled in the depths of the Deep Challenger can not only survive its extreme conditions, but also absorb the hydrocarbon molecules present in crude oil and natural gas.
Such oil – eating bacteria are also found on the surface of the ocean and have contributed to the degradation of much of the hydrocarbon waste that has spilled into the Gulf of Mexico. after the 2010 Deepwater Horizon disaster. Scientists believe that these deep-sea microbial oil eaters can also be used to clean up oil spills.
A contract employee recovers oil from the Deepwater Horizon oil spill on a beach in Grand Isle, Louisiana.Reuters / Lee Celano
Deep Challenger is "inhospitable to almost all organisms on the planet – cold and completely black.What is most extreme is the intense water pressure that would crush most organisms in a split second," Jonathan Todd , biologist at the University of East Anglia. in the UK and co-author of the study, said Business Insider.
"The way microorganisms survive this environment remains a mystery and this is another of our key research questions for the future," he added.
Collection of samples 7 miles below the surface
Sampling samples in the deep depths of the Challenger Deep is not a trivial matter. To date, only a few expeditions have investigated the inhabitants who are settling their homes 11 km below the surface of the ocean (sorry for the Jason Statham fans, no living megaladon has ever been discovered).
Deep Discoverer, a remotely operated vehicle, monitors a 12-meter (46-foot) hydrothermal vent during a deep-water exploration of the Marianas Trench. NOAA Office of Ocean Exploration and Research / AP
In order to obtain samples, researchers dumped bottles and cores in the ocean and collected water and sediment at different depths of the Marianas Trench.
"Just think of the size and weight of the cable needed to fish more than 10 km deep [or 6 miles], "Says Todd.
After reviewing their samples, the team identified a new group of oil-eating bacteria and determined that the proportion of bacteria nibbling hydrocarbons in the Mariana Trench is higher than anywhere else on Earth. (These bacteria are present in almost every environment on the planet.)
Todd and his team do not know yet why this is the case. "It may be that there is a higher proportion of hydrocarbons compared to other nutrient sources in the Marianas Trench, which supports this particularly large population," Todd said. These hydrocarbons could accumulate in the trench because of its unique topography, he added.
The authors of the study believe that hydrocarbon nutrients could be the secret to the success of this bacterium in the extreme environment of the Challenger Deep, where pressures reach about 15,000 pounds per square inch, more than 1,000 times the pressure at sea level.
These grapple microbes could fight human spills
Oil-eating organisms have already been used to help degrade man-made spills.
In 2010, the Deepwater Horizon spill off the Louisiana coast spilled some 200 million gallons of oil into the Gulf of Mexico. An area the size of Rhode Island has been closed to fishing and local economies have been ravaged.
Several species of bacteria consuming hydrocarbons, such as Alcanivorax borkumensis, have feasted on spilled oil, helping with cleanup efforts in the event of a disaster.
Alcanivorax was one of the types of bacteria that Todd and his group found in the Deep Challenger.
Industrial ship in oil spill, Gulf of Mexico, Mississippi. Nic Kirschner / Getty
Todd thinks that it is possible that the bacteria extracted from the Mariana pit also contribute to the cleaning of oil spills. When tested in the laboratory, these ocean-deep microorganisms "consumed very efficiently" the types of hydrocarbons that surface bacteria, such as Alcanivorax borkumensis degraded after the 2010 oil spill in the Gulf.
Although Todd stated that additional work was needed to "test the potential of these new bacteria," the team believes that bacteria that consume hydrocarbons at the bottom of the ocean could consume any oil found at the area.
