Wednesday, August 10, 2022
HomeUncategorizedMysterious Desert Bacterium Has Evolved Its Own, Unique Ability to Photosynthesize

Mysterious Desert Bacterium Has Evolved Its Own, Unique Ability to Photosynthesize

by Science Alert


Photosynthesis literally changed the course of history. Plants ‘eating’ sunlight and ‘breathing out’ oxygen transformed the Earth’s entire atmosphere into the one we now breathe, supplying energy to our ecosystems.

Researchers have now captured a cunning species of bacteria using stolen photosynthetic technology. And their light-eating molecular device is unlike anything we’ve ever seen.

“The architecture of the complex is very elegant. A real masterpiece of nature,” says Michal Koblizek from the Czech Academy of Sciences’ Institute of Microbiology. “It has not only good structural stability, but also great light harvesting efficiency.”

While we know of plenty of photosynthetic bacteria already, what’s happening inside Gobi desert dwelling Gemmatimonas phototrophica is unique. 

Sometime during the bacterium’s history, it stole a whole suite of photosynthesis-related genes from a more ancient proteobacterium â€“ a completely different phylum of bacteria.

This shows off the power of bacteria’s horizontal gene-transfer skills (notorious for easily spreading antibiotic resistance), allowing an entirely different type of organism to obtain sunlight-eating powers.

This new-to-science, highly stable, sunlight-capturing complex of molecules has a central reaction center, an inner sunlight-capturing ring seen before in other bacteria, and a new type of outer ring.

Together, these three components make it larger than previously described photosynthesizing complexes.

Gemmatimonas phototrophica’s photosynthetic complex. đź“· Tristan I. Croll/University of Cambridge

The outer rings snare sunlight, with the extra ring adding 800 and 816 nm absorption bands to the inner ring’s 868 nm absorption. They then direct their captured photons toward the reaction center, where chromophores, such as the green chlorophyll pigments found in plants, can be found.

This is where photosynthesis occurs. The captured sunlight excites the chromophores, causing them to transfer electrons along a path that induces atoms from water into a series of carbon dioxide-based reactions that produce sugars.

The light particles become some of the bonding energy that holds the sugar molecules together – the same ones that we animals can then break apart to obtain energy.

While this photosynthesizing structure would take more energy to build than other more familiar types, the researchers explain, “this could be offset by its extraordinary stability and the robustness of the… complex likely represents an evolutionary advantage.”

“This structural and functional study has exciting implications because it shows that G. phototrophica has independently evolved its own compact, robust, and highly effective architecture for harvesting and trapping solar energy,” says University of Sheffield structural biologist Pu Qian.

One day, we in turn may also be able to steal G. phototrophica’s ancient photosynthesis secrets to build a future of solar-powered synthetic biology.

Related articles

Stay Connected


Latest posts