A new look at the extremophiles found in an Antarctic lake reveal an especially promiscuous bunch, according to a new study.
Published in the Proceedings of the National Academy of Sciences, the report examines organisms located in Deep Lake, which formed 3,500 years ago when the Antarctic continent rose and isolated a section of the ocean. The water in Deep Lake is so salty it remains in liquid form down to -20 degrees Celsius.
In an effort to understand how the organisms there are able to withstand such extreme conditions, researchers from the University of South Wales took water samples from varying depths and studied their entire genome.
The microbes they found belong to a group known as haloarchaea, which are famous for their "promiscuity" -- a term they arrived at swapping DNA among themselves.
"But our research shows these ones swap much more genetic material with each other than has been observed in the natural environment before," Rick Cavicchioli, a professor in the university's School of Biotechnology and Biomolecular Sciences and team leader, said in a statement. "Long stretches of virtually identical DNA are exchanged between different genera, not just species."
Still, the species are able to maintain their separate identities and successfully coexist because, Cavicchioli explains, "they have evolved to exploit different niches and consume different food sources." Some live off the proteins found in the water while others consume sugars from the algae that lives on the lake's surface, for example.
Meanwhile, the haloarchaea are estimated to grow at an extremely slow pace, reproducing a mere six generations annually.
The research, Cavicchioli says, could have significant industrial implications.
"Enzymes from cold-adapted microbes could have significant value," he said. "Their high activity in cold temperatures could provide reduced energy costs for processes that would otherwise require heating, such as cleaning, or which must be carried out at cold temperatures, such as food production or bioremediation of cold, contaminated sites."
According to Cavicchioli: "This illustrates just how valuable and unique Antarctic lakes can be and why Antarctica