on Oct 17, 2020)For a decade, Dr Ram Karan has been looking for the answer to one question — how does life survive, and thrive, in extreme conditions? While he looked for answers on Earth, the discovery of liquid “water” bodies (as opposed to frozen) on Mars with exactly the kind of extreme conditions he analyses means his work could hold the key to understanding extraterrestrial life.
Over the past two years, there has been a lot of debate over the presence of “liquid water” on Mars. On September 28, a study in ‘Nature’ confirmed the presence of a subglacial lake on Mars first identified in 2018 and detected three others around it. How did they stay liquid though? Salt, it seems, is the answer. The freezing point of salt water is much lower, meaning it has to be colder for it to turn into ice. “The reason it’s still not frozen despite an average -60°C temperature is the high salt content,” said Karan.
This is where his work comes in. The 37-year-old enzymology research scientist at the King Abdullah University of Science and Technology in Saudi Arabia.
He has been studying extremophiles, microorganisms that thrive in inhospitable conditions — no oxygen, sub-zero temperatures, salt content that would kill most organisms — of the Red Sea, Antarctica and others.
“We found similar conditions in Deep Lake Antarctica. The most intriguing part was that despite high salt content, we extracted extremozymes (enzymes derived from extremophiles). This strengthens the possibility of existence of such enzymes, the building blocks of life, on Mars as well,” he said.
In his paper published in ‘Microorganisms’ journal on Friday, Karan, who is the lead author, wrote, “Studies of extremophilic proteins may not only help to understand the early evolution of life on Earth, but also provide clues for how life could potentially survive on other planets.” A paper he co-authored in 2017, which documented the discovery of an Antarctic microorganism in the ‘Proceedings of the National Academy of Sciences of the United States of America’, had also said, “The molecular basis for its survival is relevant to the search for life on Mars, as well as on the many newly discovered planets in our galaxy.”
In fact, the ‘Nature’ paper about buried lakes on Mars refers to the icy lakes of East Antarctica: “Several previously undetected subglacial lakes have been found by applying some of the criteria originally used in East Antarctica.” So, the first possible application of Karan’s research could be exploring the possibility of life beyond Earth. “It is not only important for understanding survival under extreme terrestrial environments but may also enhance our understanding of the potential for life to exist beyond planet earth,” said Dr Tune Usha from the National Center for Coastal Research, Union ministry of earth sciences.
Then, it could provide the closest possible match of Martian ecosystems. The field of astrobiology, to a large extent, depends on that. “His research on enzymes from extremophiles will enhance our understanding of life throughout the universe. These studies give scientists a window into how life could have evolved and adapt to exist on Mars,” said Thorsten Allers, professor of archaeal genetics at the University of Nottingham. So, when Martian samples are analysed, Karan’s research could help provide a framework. “In the future, when we are able to examine Martian salt samples for signs of life, we will rely on such analyses of Earth life,” said biologist Bonnie K Baxter, director of Salt Lake Institute, Westminster College.
Finally, it could hold a clue to how life functions when it does survive. Terry McGenity, professor of environmental microbiology at the University of Essex, said, “His research extends our understanding of how microbes function in extreme environments on our planet and potentially beyond Earth.”
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