Heat-loving bacteria found in the Arctic seabed have their origins in oil springs and the depths of the Earth's crust. This is the finding of a project supported by the Austrian Science Fund FWF, which used molecular biology to study "misplaced" bacteria such as these. The possibility that molecular biology could also help track down oil fields gives the project an interesting economic twist.
They were discovered over 50 years ago but their origins have remained a mystery. Living in the sediment of the Arctic seabed around Spitsbergen are bacteria that only really thrive in temperatures above 50 degrees Celsius. In fact, the term "living" can only be applied in the loosest of terms, as the bacteria found here exhibit little in the way of metabolic activity and spend their existence as dormant spores. But it is their metabolism that is of most interest, since some of them are "sulphate-reducing microorganisms" (SRMs) and as such are capable of breaking down organic material in the absence of oxygen and the presence of sulphate. It is precisely this capability that gave the first indications of where these microbial migrants could originate from.
From the Depths
"While we would describe conditions in certain parts of our planet as inhospitable, others feel right at home there. Thermophilic SRMs love environments where temperatures exceed 50 degrees Celsius and where there is a distinct lack of oxygen. In conditions such as these, these microorganisms are able to break down organic material," explains Project Leader Dr. Alexander Loy from the Department of Microbial Ecology at the University of Vienna, adding: "Underwater oil springs and ecosystems deep in the Earth's crust offer just such conditions and were our first thought when trying to pin down the origins of thermophilic SRMs in Arctic sediment."