PETERSHAM — Scientists studying soil samples at the Harvard Forest have made an unexpected discovery.

Jeffrey Blanchard, associate professor in the biology department at UMass Amherst, said that since 2018 he has worked with Matthias Fischer and Ulrike Mersdorf of the Max Planck Institute for Medical Research in Heidelberg, Germany, studying the soil in Harvard Forest to see the effects of increased temperature on microbial organisms. Cables placed underneath the soil in 2001 by Jerry Melillo—distinguished scientist at the marine biological laboratory at the University of Chicago—have warmed it by five degrees as part of an ongoing experiment.

During the process of isolating and marking the cells [in 2018 collaboration with researchers (Frederick Schulz and Tanja Woke) at the Joint Genome Institute in Berkeley, California], the researchers found DNA from new types of viruses that Blanchard said was “definitely a new species.” 

In this new study using Transmission Electron Microscopy (TEM), in collaboration with Matthias Fischer and Ulrike Mersdorf of the Max Planck Institute for Medical Research in Heidelberg, Germany, they have visualized some of these new giant virus species. Among the unique features was the size, far larger than most virus types, along with appendages—which include fibers of different lengths and thicknesses, internal channels, unique vertex structures, and tails—that could be used for attaching to other cells.

“There are some characteristics that make them viruses and not bacteria, such as shapes and appendages,” he said.

Analysis of soil samples was done by the Department of Biomolecular Mechanisms at the Max Planck Institute. Electron microscopy was used to analyze the samples and other microscopic species which were found. In a report, it was stated that advances in this technology are needed to explore further.

“Our study raises the question whether the extraordinary diversity of viral morphotypes is more typical of soil ecosystems, or whether appendage-bearing giant VLPs (virus-like particles) are also common in aquatic environments,” the report stated.

Blanchard added that the virus hasn’t been fully studied, as extracting DNA or gene sequencing destroys the sample and more must be collected. However, he said it’s not likely to be harmful to humans and would seek out soil microorganisms as hosts.

In the report, it was written that “we found that Harvard Forest soils contain a higher diversity of giant VLP morphotypes than all hitherto isolated giant viruses combined.” Blanchard added that there could be tens of thousands of species in a single teaspoonful of dirt.

“In the soil, about 99 percent of the virus and bacteria species haven’t been isolated,” Blanchard said. “There’s a lot that’s unknown so we expect to be finding new species every time we go in to look.”

Blanchard said that more study is needed and plans to return to Harvard Forest and other woodlands to seek out giant virus species, hoping to find them within the next decade. In particular, he’s interested in seeing what the giant viruses found in the Harvard Forest do when outside of a host.

Much of the work’s focus will be on the region around the Quabbin and working with the National Ecological Organization Network.

“Each year I’m further appreciating the diversity there,” Blanchard said.

Max Bowen can be reached at 413-930-4074 or at mbowen@recorder.com.

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