Researchers found dozens of new viruses in ice cores 15,000 years ago
Glaciers are very good at preserving deep history because they Dust particles, gas traces, microorganisms and plant matter from different periods are captured. As these layers accumulate over time, scientists can drill and study ice cores to learn a lot about ancient climates, materials in the atmosphere, and the types of life that existed in different historical periods.
In this new study led by researchers at Ohio State University, an ice core was drilled from the Gulia Ice Sheet on the Qinghai-Tibet Plateau, dating back to 14,400 years ago. The research team then analyzed the types of viruses contained in these ice cores and determined the genetic codes of 33 viruses. Four of them were found to belong to the known types of bacteriophages, namely viruses that prey on bacteria, but at least 28 of them did not fit any known types.
The research team hypothesized that these viruses may originate in plants and soil, but they are not necessarily blocked by the cold – in fact, about half of them seem to be suitable for living on ice.
The study’s co-author Matthew Sullivan Said: “These are viruses that thrive in extreme environments.” These viruses have genetic features that help them infect cells in cold environments-how a virus can survive under extreme conditions is just a surreal genetic feature . ”
Contamination of modern microorganisms is a serious problem for this kind of research, so the researchers developed a new ice core disinfection method. They used different techniques to remove half a centimeter (0.2 inch) of the outer layer. Materials-firstly scraping with a band saw, then washing with ethanol, and finally washing with sterile water. Then the inner part of the ice core can be inspected without contamination.
This disinfection process was tested on ice cores. These ice cores were coated with bacteria, viruses and DNA. After three steps of treatment, no traces of these simulated pollutants were found in the internal ice cores.
Researchers say that being able to better study ancient microbes can help scientists better understand their evolutionary history and how they have dealt with the changing climate in the past and in the future. This disinfection method can also be used in the search for the moon or Traces of viral gene sequences in samples collected on Mars come in handy.
This research was published in the journal Microbiome.