Researchers at the Department of Energy’s Lawrence Berkeley National Laboratory and the University of California, Berkeley announced last week that they had managed to photograph the smallest known life on Earth. The possibility of ultra-small bacteria has been theorized for over 20 years, but this study is the first electron microscopy and DNA-based description of the tiny microbes.
The team published their study in the February 27th edition of the academic journal Nature Communications.
More on the smallest known life
The cells of the newly discovered tiny bacteria have an average volume of just 0.009 cubic microns. That means more than 150 of them could fit inside a single Escherichia coli bacteria cell and it would take more than 150,000 to cover the tip of a human hair.
The new bacteria were actually found in common groundwater. The researchers note that the tiny cells are close to estimates for the lowest possible for life. This new bacteria arguably represents the smallest a cell can be and still sustain life. These bacteria feature tightly packed spirals that are probably DNA, very few ribosomes, and an extremely basic metabolism that means they require other bacteria for some of life’s necessities.
The Berkeley Lab researchers determined that the bacteria come from three separate microbial phyla. Studying the new species from these phyla could help scientists understand the role of microbes in our food and water supply as well as their impact on weather and climate processes.
Statement from researcher
“These newly described ultra-small bacteria are an example of a subset of the microbial life on earth that we know almost nothing about,” commented co-author Jill Banfield, a UC Berkeley professor in Earth and Planetary Science and Environmental Science, Policy and Management.
“They’re enigmatic. These bacteria are detected in many environments and they probably play important roles in microbial communities and ecosystems. But we don’t yet fully understand what these ultra-small bacteria do,” Banfield also noted.