New Oxygen research; photosynthesis early appearance? (Introduction)

by David Turell , Thursday, March 25, 2021, 20:33 (1130 days ago) @ Balance_Maintained

Photosynthesis may have started earlier than thought:

https://www.sciencedaily.com/releases/2021/03/210324142839.htm

"Researchers find that the earliest bacteria had the tools to perform a crucial step in photosynthesis, changing how we think life evolved on Earth.

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"Lead researcher Dr Tanai Cardona, from the Department of Life Sciences at Imperial, said: "We had previously shown that the biological system for performing oxygen-production, known as Photosystem II, was extremely old, but until now we hadn't been able to place it on the timeline of life's history. Now, we know that Photosystem II show patterns of evolution that are usually only attributed to the oldest known enzymes, which were crucial for life itself to evolve."

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"The new research finds that enzymes capable of performing the key process in oxygenic photosynthesis -- splitting water into hydrogen and oxygen -- could actually have been present in some of the earliest bacteria. The earliest evidence for life on Earth is over 3.4 billion years old and some studies have suggested that the earliest life could well be older than 4.0 billion years old.

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"On Earth, it took more than a billion years for bacteria to perfect the process leading to the evolution of cyanobacteria, and two billion years more for animals and plants to conquer the land. However, that oxygen production was present at all so early on means in other environments, such as on other planets, the transition to complex life could have taken much less time.

"The team made their discovery by tracing the 'molecular clock' of key photosynthesis proteins responsible for splitting water. This method estimates the rate of evolution of proteins by looking at the time between known evolutionary moments, such as the emergence of different groups of cyanobacteria or land plants, which carry a version of these proteins today. The calculated rate of evolution is then extended back in time, to see when the proteins first evolved.

"They compared the evolution rate of these photosynthesis proteins to that of other key proteins in the evolution of life, including those that form energy storage molecules in the body and those that translate DNA sequences into RNA, which is thought to have originated before the ancestor of all cellular life on Earth. They also compared the rate to events known to have occurred more recently, when life was already varied and cyanobacteria had appeared.

"The photosynthesis proteins showed nearly identical patterns of evolution to the oldest enzymes, stretching far back in time, suggesting they evolved in a similar way.

"First author of the study Thomas Oliver, from the Department of Life Sciences at Imperial, said: "We have used a technique called Ancestral Sequence Reconstruction to predict the protein sequences of ancestral photosynthetic proteins. These sequences give us information on how the ancestral Photosystem II would have worked and we were able to show that many of the key components required for oxygen evolution in Photosystem II can be traced to the earliest stages in the evolution of the enzyme.'"

Comment: The mechanism of photosynthesis is vital for life to become complex, which occurred after the Great Oxygenation Event. Looking at the early timing of development, it seems to me to be carefully planned and designed by God.