Could deep-sea bacteria be the latest weapon against climate change?

Researchers from the University of Florida have discovered certain bacteria on the ocean floor could neutralize massive quantities of industrial carbon dioxide.

Because carbon dioxide, the primary greenhouse gas emitted by human activity, is a key culprit in climate change, scientists from a variety of disciplines have been searching for ways to effectively capture and neutralize the gas.

The UF researchers discovered that an enzyme produced by the bacteria Thiomicrospira crunogena, can convert the harmful gas into a benign compound. The enzyme carbonic anhydrase can actually strip carbon dioxide from organisms, the researchers say.

Because this bacteria lives by hydrothermal vents, it has adapted to withstand the scalding temperatures involved in sequestering carbon dioxide from the power plant emissions.

“This little critter has evolved to deal with those extreme temperature and pressure problems. It has already adapted to some of the conditions it would face in an industrial setting,” Robert McKenna, a professor of biochemistry and molecular biology in the UF College of Medicine, said.

One catch to this solution is that this process needs copious amounts of carbonic anhydrase, but McKenna’s team discovered a way to obtain the enzyme without having to continuously scoop it up from the ocean floor.

Using a genetically engineered form of the E. coli bacteria, the enzyme can actually be harvested in a laboratory setting. So far, however, the researchers have only made a few milligrams of the carbonic anhydrase, and much more would be needed to put a dent in the atmosphere’s massive accumulation of carbon dioxide.

Another challenge the researchers face is speed: the enzyme the researchers studied does not work particularly fast.

“You want it to do the reaction faster and more efficiently,” said Avni Bhatt, a research assistant. “The fact that it has such a high thermal stability makes it a good candidate for further study.”

The UF researchers aren't the only scientists looking to the ocean for catalysts that can neutralize carbon dioxide. Last month, The Christian Science Monitor reported on how tiny sea creatures may be acting as crucial carbon sinks:

After accounting for help from other underwater species, bryozoans are responsible for an increased carbon drawdown of about 2.9x106 tons per year – equivalent to 50,000 hectares of tropical rainforest. 'As sea ice is lost, more and more carbon will be buried in the sea, whereas the same is not true on land so the balance will be changing,' says [researcher David] Barnes.