Madrid, 17 (European press)
A strange bacterium discovered eight years ago in Tian Yi Ho (Swan Lake) in the Gobi Desert is capable of harvesting solar energy.
The new organism belongs to a rare bacterial genus called Gemmatimonas, and contains bacterium chlorophyll, a pigment related to chlorophyll found in plants. Analysis of its genome by the collaboration of European and British scientists suggested that this new bacterium performs an ancient form of photosynthesis.
“This structural and functional study has exciting implications as it shows that G. phototrophica independently developed its compact, robust and highly efficient structure for solar energy harvesting and trapping,” lead author Dr. Bo Qian says in a statement.
In their research paper published in Science Advances, the team demonstrates how this mysterious object harvests light energy. They explain how they used cryo-electron microscopy collected from four different laboratories, including Diamond Light Source in the UK.
Their work revealed the detailed structure of the photosynthetic complex, which consists of 178 pigments bound to more than 80 protein subunits. The light-harvesting subunits are arranged in two concentric rings around the reaction center that convert the absorbed light energy into an electric charge. “The architecture of the complex is very elegant. “It’s a true masterpiece of nature,” says Dr. Michal Koplesic from the Institute of Microbiology in the Czech Republic. “It not only has good structural stability, but also has high light-gathering efficiency.”
Since the pigments in the outer ring have higher energy than the pigments in the center of the ring, the entire network acts as a funnel. The energy absorbed by the pigments in the periphery of the complex is transferred several picoseconds down the energy gradient to the center of the complex, where it is converted into metabolic energy.