15,000 year old viruses have not been found in the Tibetan glacier

Melting ice at high latitudes and altitudes not only raises concerns about the climate, but also raises concerns about organisms trapped in permanent snow, in addition toVery well protected animals And Strange bacteria, Unknown viruses existed thousands of years ago. Recently, researchers identified several unknown viruses that are 15,000 years old lying in the Gulia Glacier on the Tibetan Plateau.

Earth’s distant past organisms, animals, bacteria or viruses, reveal the history of ancient ecosystems, including details of the environments in which they lived. But concerns about the return of melting old pathogenic viruses are often unjustified.

« Melting not only destroys these ancient and archived microbes and viruses, but also releases them into the environment. Researchers write in a new study led by microbiologist Ji-Ping Zhang of Ohio State University.

28 previously unknown viruses

Using new metagenomic techniques and new methods to sterilize ice samples, researchers are working to better understand exactly what is hidden in these organisms. In a new study, the team was able to identify an archive of dozens of unique viruses 15,000 years old from the Gulia ice sheet of the Tibetan Plateau and better understand their functions. The results were published in the journal Microbial.

« These glaciers gradually formed, along with dust and gas, causing many viruses to accumulate in the ice. Z Zhang says In a press release. These microorganisms refer to those present in the atmosphere at the time of their deposition, the group explains in its study.

In fact, Previous studies Microbial communities have been associated with changes in dust and ion concentrations in the atmosphere, and may also indicate climatic and environmental conditions at that time. In this ancient frozen record at an altitude of 6.7 kilometers above sea level in China, researchers found that 28 of the 33 viruses they detected had never been seen before.

« These are viruses that thrive in extreme environments Says Matthew Sullivan, a microbiologist at Ohio State University; Genetic signatures that help cells to survive in cold climates – Surreal genetic signatures that show how a virus can survive in extreme conditions. .

Where do they come from?

By comparing their genetic sequences with a database of known viruses, the team found that the most common viruses in the two ice core samples were bacteriophages capable of infecting methylobacteria – bacteria important Methane cycle In the snow.

They are most closely related to viruses found in strains of methylobacteria in plant and soil habitats, which is a Previous report Accordingly the main source of dust accumulated in the Gulia ice may have come from the soil.

« These frozen viruses emerge from the soil or plants and help their hosts get nutrients. 2, concluded the research team. While the discovery of ancient viruses may seem particularly troubling in the midst of an epidemic, the greatest risk for ice melting lies elsewhere: separate methane and carbon reserves are released into the atmosphere … but ice may also contain information about past environmental changes, as well as the evolution of viruses. Valuable information.

« We know very little about viruses and bacteria in these extreme environments, what really exists. Researcher Lonnie Thompson says many important questions remain unanswered. ” How do bacteria and viruses respond to climate change? What happens when we move from an ice age to a warmer time like the one we are experiencing now? .

Source: Microbial