Nearly 1,000 Microbe Species Have Just Been Discovered in 'Extreme' Tibetan Glaciers

0 Comments

It's difficult to survive as a microorganism on the Tibetan Plateau. Cold temperatures, high amounts of sun radiation, not much to eat, and depending on the time of year, you'd get frozen and then thawed on a frequent basis.

So it comes as a bit of a surprise that scientists have identified 968 kinds of microorganisms under these "severe environmental conditions." The discovery is the result of the first specialized genome inventory of the glacial environment.

"The surfaces of glaciers support a diverse array of life, including bacteria, algae, archaea, fungi, and other microeukaryotes. Microorganisms have demonstrated the ability to adapt to these extreme conditions and contribute to vital ecological processes," the team says in their new research.

"Glacier ice can also act as a record of microorganisms from the past, with ancient (more than 10,000 years old) airborne microorganisms being successfully revived. Therefore, the glacial microbiome also constitutes an invaluable chronology of microbial life on our planet."

The researchers focused on a single set of glaciers - the Tibetan Plateau. This 2.5 million square kilometer region is a key water supply for adjacent Asian countries, and it has been severely affected by climate change, with over 80% of glaciers beginning to melt.

Not only is it crucial to know which bacteria exist up there (in case they become a problem for people and the ecology as the ice melts), but if we don't record which species are now present, they may become extinct due to climate change.

"Here we present the first, to our knowledge, dedicated genome and gene catalog for glacier ecosystems, comprising 3,241 genomes and metagenome-assembled genomes and 25 million non-redundant proteins from 85 Tibetan glacier metagenomes and 883 cultivated isolates," the team writes in their paper, led by Lanzhou University ecologist Yongqin Liu.

Between 2016 and 2020, the researchers made a massive effort to collect snow, ice, and dust from 21 Tibetan glaciers. They employed metagenomic approaches to capture all of the genetic material found in the samples; they also cultivated some of the microorganisms in a lab to learn more about them and extract a larger part of their genome.

Surprisingly, 82 percent of the genomes belonged to new species. A stunning 11% of the species were found exclusively in one glacier, whereas 10% were present in nearly all of the glaciers surveyed.

The initiative has evolved into the 'Tibetan Glacier Genome and Gene' (TG2G) catalog, which the researchers believe will be useful to researchers in the future when new species are discovered.

"The TG2G catalog offers a database and a platform for archiving, analysis and comparison of glacier microbiomes at the genome and gene levels. It is particularly timely as the glacier ecosystem is threatened by global warming, and glaciers are retreating at an unprecedented rate," the team notes.

"We envisage that the catalog will form the basis of a comprehensive global repository for glacial microbiome data."

The research has been published in Nature Biotechnology.