Researchers in central Finland have isolated the country’s first known giant virus, suggesting that these large, complex viruses may be more widespread in northern environments than previously believed.
The virus, named Jyvaskylavirus, was extracted from local soil by scientists at the University of Jyväskylä. It infects amoebas and measures approximately 200 nanometres in diameter, roughly twice the size of influenza or coronavirus particles.
“This discovery expands our understanding of viral diversity in northern ecosystems,” said Professor Lotta-Riina Sundberg, who led the study. “It highlights how much remains unknown about the structure and function of these unusual viruses.”
Giant viruses differ from most in both size and genetic complexity. While typical viruses have small genomes and infect animal or plant cells, giant viruses target unicellular organisms and often carry genes previously thought to be unique to cellular life. Their size and genetic content continue to fuel debate about their evolutionary origins.
Jyvaskylavirus was found by mixing environmental soil samples with Acanthamoeba castellanii, a common freshwater amoeba. The resulting virus particles, though still microscopic, are considered “giant” due to their unusually large diameter and DNA content.
Microscopic imaging revealed the virus’s structure, and genome sequencing linked it to the Marseillevirus family, previously known from southern Europe, particularly France. The finding makes Jyvaskylavirus the northernmost member of this viral group.
The research, published in eLife, also identified traces of other large viruses in the Finnish samples, suggesting that similar viruses may be common in local soils and waters.
“Giant viruses likely play a significant role in regulating microbial populations,” Sundberg said. “This helps shape ecosystems by influencing the abundance and diversity of other microscopic life.”
According to the study, giant viruses could be important agents in nutrient cycling and microbial interactions. They may also provide a new lens through which to understand virus evolution.
Viruses in general are the most abundant biological entities on Earth, yet their diversity and ecological roles remain poorly mapped. This is especially true for giant viruses, which have only begun to be widely studied over the past two decades.
The Jyvaskylavirus genome is still being analysed to understand its functions and evolutionary relationships. Researchers hope the discovery will help answer broader questions about the origins of viruses and their place in the tree of life.
The team involved in the study included Finnish and international scientists from institutions in Brazil, Italy, France and Spain.
“Each discovery like this one adds a piece to the puzzle,” said Sundberg. “We are just beginning to understand the hidden world of these giant viruses and their impact on ecosystems.”
The virus is not known to pose any risk to humans or animals.
HT
