Why giant viruses discovered in Greenland could play a key role in the environmental crisis

Discovery of giant viruses in the ice sheet Greenland It could be a tool to help reduce ice melt in this area of ​​the planet and help combat climate change.

The fact is that, according to a study conducted by scientists from the Department of Environmental Sciences Aarhus University (city)Denmark), these viruses probably regulate the growth of snow algae on ice by infecting them. Therefore, at the same time, its function is key in the conditions of the environmental crisis that the planet is experiencing.

This is due to the fact that, as is known, algae are dormant on the ice during the autumn and winter months. They begin to bloom in the spring, blackening large areas of ice. Thus, its ability to reflect the sun is reduced, and this accelerates its meltingwhich worsens global warming.

The paradox of the discovery, the researchers highlighted, is that viruses tend to be significantly smaller than bacteria, with typical sizes ranging from 20 to 200 nanometers, compared to bacteria, which average 2 to 3 micrometers in size.

That is, an ordinary virus is about a thousand times smaller than a bacterium. However, this is not the case with giant viruses, which, as seen in the study, can reach sizes of up to 2.5 micrometers, thus surpassing most bacteria.

But, in addition, they are not only large in size, but also They have a much larger genome than regular viruses.. While bacteriophages that infect bacteria can have between 100,000 and 200,000 letters in their genome, giant viruses have about 2,500,000 letters, making them significantly different in their genetic complexity.

To this should be added post-doctoral training. Laura Periniwho is one of the first authors of the recent work, emphasized that “for the first time, giant viruses have been discovered living on the surface of ice and snow, where microalgae dominate.”

“Giant viruses were first discovered in 1981, when researchers discovered them in the ocean,” the expert said. These viruses specialized in infecting green seaweeds. Later, giant viruses were discovered in the soil of the Earth and even in humans.”

And after pointing this out “Not much is known about these viruses”A researcher at the Department of Environmental Sciences at a Danish university analyzed: “I think they could be useful as a way to alleviate ice melting caused by algae blooms. How specific they are and how effective we don’t yet know. But by studying them further, we hope to answer some of these questions.”

Although scientists called the viruses they found “giants,” the truth is that They are not visible to the naked eye. By the way, Perini herself assured that she had not yet seen them under an optical microscope either.

So how did they find them? “The way we discovered viruses was analysis of all the DNA from the samples we took – the expert clarified. “By examining this huge data set for specific marker genes, we discovered sequences that have strong similarities to known giant viruses.”

Then, to make sure that the viral DNA did not come from long-dead microorganisms, but from living, active viruses, all the mRNA was also extracted from the sample. And when the DNA sequences that make up genes are activated, they are transcribed into single-stranded fragments called mRNA. “These pieces act as recipes to create the proteins needed by the virus. If they are present, the virus is alive,” Perini said.

“In the total mRNA sequenced from the samples, we found the same markers as in the total DNA, so we know they were transcribed. This means that the viruses are alive and active in the ice,” he concluded.