Giant viruses, however, are not like that. They grow to 2.5 micrometers in size, and larger than most bacteria.
In addition, the genomes of giant viruses are also much larger than those of normal viruses. Bacteriophages have between 100,000 and 200,000 letters in their genomes, while giant viruses have about 2,500,000 letters.
Giant viruses were first discovered in 1981, when researchers found them in the ocean. These viruses specialize in spreading green algae in the sea. Later, giant viruses were found in soil on land, and even in humans.
“But this is the first time giant viruses have been found living on the surface of ice and snow, mainly microalgae.”Perini explained.
“We analyzed samples from black ice, red snow, and tiny depressions in the ice, called cryoconite holes. In both black ice and red snow, we found signs of active giant viruses. This is the first time they have been found on the surface of ice and snow that contain a lot of pigmented microalgae.”she said.
Presence of mRNA
Algae blackens ice in Greenland. (Photo: Laura Perini).
Despite their enormous size, these viruses escape observation by the human eye and even conventional microscopes. “Our discovery was made by analyzing DNA from collected samples” – Ms. Perini said and provided more information, they screened large datasets to find signs of giant viruses.
mRNA (short for “messenger RNA”)a type of RNA that plays an important role in protein synthesis in cells. mRNA is rapidly degraded unless actively produced by living organisms. The presence of mRNA in the region further confirms the activity of giant viruses on ice.
Although the potential of these giant viruses to control algae and mitigate ice loss due to global warming is promising, much remains unknown.
“Their exact hosts and mechanisms remain unclear. Some may target protists directly, others target algae directly.” – Ms. Perini noted. Her research aims to further understand these interactions, with more findings expected to be published by the end of 2024.
According to Tuoi Tre/GDTĐ