Scientists Isolate Microbes That Eat Carbon Dioxide
Life on Earth is a fascinating subject. There are organisms that thrive in hot sulfurous pools inside the calderas of volcanoes and others that love the icy tops of the world’s tallest mountains where oxygen is scarce. Others swim in the deepest parts of the ocean where sunlight never penetrates and pressures are many hundreds of times greater than they are at the surface.
In September of last year, scientists who are part of the 2 Frontiers Project traveled to the Italian island of Vulcano (the name says it all) where some of the water seeping from beneath the dormant volcano contains high levels of carbon dioxide. A team of divers collected many samples of seawater ranging from low to high in carbon dioxide. Then they prepared the samples in a field lab where paired DNA sequencing and culturing experiments were carried out.
The results will allow the researchers to characterize and utilize the evolution of life along a dissolved carbon gradient. The team is in the process of culturing novel carbon capturing organisms from these samples and building a living database for use by the scientific community. A second research program is now underway at a hot spring in the Rocky Mountains where the concentration of carbon dioxide is even higher. Those samples are now in the process of being analyzed.
Gobbling Up Carbon Dioxide
What the scientists found in those warm waters in Italy is microbes that gobble up carbon dioxide “astonishingly quickly,” they told The Guardian. They now hope to utilize those microbes to absorb carbon dioxide as an efficient way of removing it from the atmosphere. Ending the burning of fossil fuels is critical in ending the climate crisis, but most scientists agree carbon dioxide will also need to be removed from the air to keep average global temperatures from spiraling out of control to the point where humans will no longer be able to inhabit the Earth.
The new microbe, called a cyanobacteria, turns carbon dioxide into biomass faster than any other known bacteria. The researchers said all their data on microbes would be published and made available to other scientists as a database that pairs DNA sequences with banked samples of the bacteria.
Dr. Braden Tierney, a professor at the Weill Cornell Medical College and Harvard Medical School, said, “Our lead collaborator at Harvard isolated this organism that grew astonishingly quickly, compared to other cyanobacteria. The project takes advantage of 3.6 billion years of microbial evolution. The nice thing about microbes is that they are self-assembling machines. You don’t have that with a lot of the chemical approaches [to carbon capture].”
The new microbe had another unusual property, Tierney said. It sinks in water, which could help sequester the carbon dioxide it absorbs. Still, the cyanobacteria is not a magic solution to the problem of too much carbon dioxide in the atmosphere. “There really isn’t a one size fits all solution to climate change and carbon capture. There will be circumstances where the tree is going to outperform microbes or fungi. But there will also be circumstances where you really want a fast growing aquatic microbe that sinks,” he said. They might be utilized in large, carbon capturing ponds, he said. They also might be able to produce a useful bioplastic.
The project was funded by the biotechnology company Seed Health, which has also employed Tierney as a consultant. The company already sells probiotics for human health, has developed a probiotic for bees, and is researching the use of microbial enzymes to break down plastics.
“Seed Health was founded on the belief that by unlocking the immense potential of the microbiome, we possess the power to make transformative strides in human and planetary health,” said its co-chief executive Raja Dhir. “Our work with Dr Tierney is exactly in line with that mission and may help to unlock new models [for] carbon capture.”
Genetic Engineering & Carbon Dioxide
The idea of using bacteria to capture carbon dioxide is an active area for researchers around the world. A research paper last year included an exhaustive review of that research and came to the following conclusion:
“CO2 capture by bacteria is an appealing option for climate change mitigation and immediately creating bio-based commodities with added value from CO2. However, to extend the production of these valuable commodities from CO2, revolutionary innovations encompassing major biotechnological methods (synthetic biology, and metabolic and genetic engineering) will need to be used and further developed.
“In this review, various novel genetic engineering and synthetic approaches employed in the engineering of bacteria for improved CO2 capture and utilization were discussed. With a growing emphasis on climate remediation, the use of bacteria targeted at a severe lowering in the addition of value to the carbon dioxide extracted, the use of waste raw materials, and footprint will be the ones to watch in the future.
“The emerging picture from this review highlights the need for future studies should focus on the selection of efficient bacteria, genetically engineering alterations as well as designing and building synthetic metabolic pathways. Doing so will help to reduce the cost of production of value-added bio-based products via CO2 capture and conversion by bacteria.
“Finally, integrating bacteria CO2 fixation in addition to other industrial operations such as treatment of exhaust gas and wastewater, refining biogas, and direct manufacture of commodities from CO2 might be more productive. This might help address the primary ecological issues of global warming while also reducing the usual cost and performance constraints in microbiological CO2 capture and conversion on a large scale as well as technological advances.”
The review suggested that bacteria could produce useful chemicals, as well as trapping CO2. “Using modified bacteria to manage CO2 has the added benefit of generating useful industrial byproducts like biofuels, pharmaceutical compounds, and bioplastics,” the researchers said.
The US company LanzaTech already uses bacteria to convert CO2 into commercial fuels and chemicals. On its website it says, “LanzaTech’s carbon recycling technology is like retrofitting a brewery onto an emission source like a steel mill or a landfill site, but instead of using sugars and yeast to make beer, pollution is converted by bacteria to fuels and chemicals! Imagine a day when your plane is powered by recycled GHG emissions, when your shampoo bottle started life as emissions from a steel mill.”
CyanoCapture, a UK company backed by Shell and Elon Musk [this is news to us!], is harnessing cyanobacteria to produce biomass and biological oils. Numerous companies are working on using algae to produce biofuels, although ExxonMobil ended its research on this recently.
Rex Tillerson, former CEO of ExxonMobil, once sneered that humans would just have to adapt to a warmer climate. It’s hard to imagine anyone so rich and powerful being so unremittingly stupid. Yes, organisms adapt, but not in a matter of years or even decades. As the 2 Frontiers Project researchers noted, it took a few billion years for the cyanobacteria to develop their appetite for carbon dioxide.
Once humans destroy the environment that sustains us — in less than a hundred years from now, based on current reports — new species may arise over the following eons. But homo sapiens won’t be around unless we do the one thing we all know is essential to preserving human life — stop extracting and burning fossil fuels.