From spreading crushed rocks in forests and farmlands to constructing green buildings with materials that suck carbon up out of the atmosphere, scientists are hard at work developing innovative solutions that reduce our greenhouse gas emissions.
More recently, a team of scientists from Washington University in St. Louis investigated the potential of microorganisms to help us tackle climate change. The study involved shedding new light on electricity-eating bacteria that may help enhance our oceans’ ability to absorb CO2.
The peculiar electricity-munching skills of these microbes — known as photoferrotrophs — were previously thought to be almost exclusive to freshwater bacteria, but the recent study shows that they may be common in marine bacteria too.
“These microbes are fixing and sequestering carbon dioxide and they can both ‘eat’ electricity and perform photoferrotrophy,” says study leader Arpita Bose. “Photoferrotrophs use soluble iron as an electron source for photosynthesis while fixing carbon dioxide. Marine environments are great places for them because they are rich in many things they need.”
In their study, the team investigated the way the bacteria consumes electrons and discovered a previously unknown electron-transfer protein that appears to be key in the process. While in a lab, the bacteria were able to harvest electrons directly from an electricity source. In the wild, they likely harvest electrons through rust and other iron minerals that are abundant in marine sediments.
According to Bose, because these bacteria are common and thriving in marine sediments, they may already hold a key for future engineered approaches to combating climate change.
“We need to understand the extent of carbon sequestration they can do in nature, as it might be a cryptic metabolism,” Bose says. “We could also potentiate it further—both for biotechnology and for the environment. This study is a big step, setting the stage for many future studies.”
Source study: ISME Journal — Photoferrotrophy and phototrophic extracellular electron uptake