BRUSSELS, Jan. 10 (Xinhua) -- The University of Liège in Belgium recently issued a communiqué saying that a research team at the university has been studying about 17 years agoThe thylakoid membrane structure has been found in a 500-million-year-old cyanobacterial fossil, the oldest known thylakoid fossil to date, about 1.2 billion years earlier than the earliest record of thylakoids. The new study provides clues to further understanding the evolution of cyanobacteria and oxygen-producing photosynthesis.
According to the communiqué, researchers at the University of Liège analyzed microfossils of the same algae contained in shale from three sites around the world. One of the oldest shales was quarried from the territory of Australia, about 17 years ago500 million years old, and two other collection strata are located in Canada and the Democratic Republic of the Congo, about 1 billion years ago.
Ultrastructural analysis of the above microfossils revealed that it was a cyanobacterial fossil. The internal membrane structure is present in the cyanobacterial fossils collected from two strata in Australia and Canada, and their arrangement, fine structure and size suggest that they are thylakoid membrane structures, which are the sites of oxygen production by the photosynthesis of plants and algae.
It is generally accepted that cyanobacteria played an important role in the "Great Oxidation Event", which occurred about 2.4 billion years ago, when the oxygen content of the Earth's atmosphere increased dramatically, but the time of oxygen production through photosynthesis and the origin of cyanobacteria with thylakoids is still uncertain. This new discovery provides a better understanding of the role that thylakoid-like cyanobacteria played in the early Earth's atmospheric oxygen increase.
The new findings could help advance research into the evolution of early life on Earth, including whether thylakoids were already present in older cyanobacteria and played an important role in Earth's "Great Oxidation Event," and when chloroplast-containing algae diverged from cyanobacteria, the communiqué said.