Team Discovers New Phylum Of Microorganisms That's Also Found In Yellowstone
The family tree of living things has a new branch - one whose members can be found in some of Yellowstone's hot springs. It's been named Brockarchaeota, and it's part of a broad category known as a phylum.
Finding a new phylum is a big deal because it doesn't happen very often. Researchers from Texas discovered Brockarchaeota by accident.
"Oddly enough, we were doing a study in the Gulf of California in the deep, deep ocean - so we were looking at sediments at 2,000 meters. And we were looking for other things, but these new microbes popped up in those samples," said Brett Baker, an associate professor at the University of Texas at Austin in the Marine Sciences Department.
Baker and his team compared the DNA from these new microbes to DNA stored in an online database and found that there are other, similar microbes that had been collected across the world.
"And it turned out that they're not that common in the deep ocean, but they're really common in hot springs, like at Yellowstone," said Baker. "So it was very weird that we found them in the deep ocean and then they turned out to be really, really widespread in hot springs."
According to Baker, these microbes hadn't been named yet but their genetic information grouped them in with the ones he had found deep in the ocean. By studying their genetic pathways, researchers found that these new microbes eat carbon, like decaying plant matter, but they don't produce methane as a waste product, as other carbon munchers do. This set them aside as their own phylum.
"We look at their genes, and we say, 'Okay, it looks like they produce things like acetate, butanol, based on their genome sequences.' So we don't entirely know for sure, but this is sort of our best guess," said Baker.
Now that more is known about these microbes and where they live, researchers can start trying to grow them in the lab to learn exactly what kinds of waste products they do produce.
"They don't have the conventional pathways or genes that organisms that produce methane do have. I mean, it would be pretty interesting if they actually did produce methane, and they had some other genes that did it that we didn't know about," said Baker. "That's entirely possible, of course. It's the one thing about biology, you can never really rule anything out, and if you do, as a scientist, you're probably not going to find anything all that new."
According to Baker, these microbes likely aren't the answer to the climate crisis, but they can give important insight into how microbial communities are involved in transforming carbon on the planet.
"The places that we've seen them, they're not superabundant. They're kind of the minor members of those communities, and oftentimes the minor members may not play a huge role in things," he said. "But given that they have sort of a unique role, I think that that in itself, you know, it's not always the dominant organisms that are the most important. It's sometimes the minor members that are important as well."
Having discovered the link between the previously unknown microbes, Baker's team named the new phylum, which was then reviewed by journal committees and became its accepted name. The members of the group that live in Yellowstone's hot springs inspired the team to name it after a pioneer in microbiology, Thomas Brock, who discovered microbes in Yellowstone's hot springs in the early 60s that are responsible for a process used in today's COVID tests and criminal DNA tests.
"He was actually one of the first to look at Yellowstone and say, 'Oh, there's a lot of microbial communities there, and we should try and understand them more.'" said Baker. "And so it just made sense since they came from hot springs that we should name them after Tom."
"I had been in contact with Tom over the last year about their naming and he said he was really honored," said Baker.