Giant viruses infect algae in an arctic floating lake
Microbiologists from Laval University have discovered giant viruses between the limit of fresh water and salt water in Milne Fjord Lake. The latter is located in Canada at approximately 800 km from the North Pole. A body of fresh water lying above sea water constitutes it. What makes it special is that it is held in place by ice.
Indeed, fresh water is lower than salt water in density. that’s why she floats in a liquid state above seawater. By the way, a layer of ice covers its surface. The latter allowing it to protect itself from bad weather that could cause it to mix with seawater.
Further study seems necessary to verify whether these viruses really pose a threat. Indeed, the researchers have not yet decided on how most viruses affect microscopic algae. In addition, they still have to identify which viruses infect which organisms.
The floating lake could disappear due to global warming
According to a press release from I’American Society for Microbiologythe researchers hope to obtain more detailed information on the ecosystem soon. However, they face another problem. Indeed, the rise in global temperature threatens to destroy the ice that holds fresh water in place.
“Platform groyne lakes used to be more common in the Arctic, but they are now extremely rare. If the ice dam breaks, which has happened in other fjords, then the Epi Lake Milne Fjord platform will be lost”.
Unusually large viruses
The ecosystem of the lake and that of the Arctic Ocean each have different properties. The virus community present is different. According to this study, the freshwater lake contains a richer and more diverse range of viruses compared to the seawater below.
The researchers drilled through the surface ice to collect some samples lake water. The sequence of DNA collected has identified a variety of viruses, including a group of giants called Megaviricetes. These latter many times larger than the normal size of a virus.
“One of the characteristics of viruses in general is that they are tiny, much smaller than the smallest bacterium, and they carry only a few genes to help them replicate.”
The researchers added that during the last 20 yearsscientists have discovered giant viruses that are as big as a bacterium.