Rubisco is one of the most abundantidases on the planet. One of the key changes of early photosynthesis has been deciphered by a team of researchers. Their results provide insight into the evolution of modern photosynthesis and also offer new impulses for improving it.
Plants andalgae capture and convert CO 2 in the present day. More than 400 billion tons of CO 2 is captured annually by the Rubiscoidase. The mass of Rubisco on our planet is larger than that of all humans. Rubisco had to adapt to changing environmental conditions in order to assume such a dominant role.
A team from the Max-Planck-Institute for Terrestrial Microbiology in Marburg, Germany in collaboration with the University of Singapore has successfully resurrected and studied billion-year-old enzymes. The researchers found that an entirely new component prepared to adapt to rising oxygen levels was the result of this process.
Rubisco was confused at the beginning.
Prior to the presence of oxygen on earth, Rubisco emerged in primordial metabolism. With the invention of oxygen-produced photosynthesis and rise of oxygen in the atmosphere, the enzyme started catalyzing an undesirable reaction in which it mistakes O 2 for CO 2 and produces toxins that are harmful to the cell. Rubiscos have been scarred by this confused scope and limits their ability to grow. Even though Rubiscos got more specific for CO 2 over time, they couldn't eliminate the oxygen capturing reaction.
Increased CO 2 specificity in Rubisco remains largely unknown. They are of interest to researchers. The Rubiscos that show increased CO 2 specificity recruited a novel component. The component was thought to be involved in increasing CO 2 specificity, however, the true reason for its emergence was not known because it already evolved billions of years ago.
A lab is being used to study evolution.
The Max Planck Institute for Terrestrial Microbiology in Marburg and Nanyang Technological University in Singapore collaborated to recreate forms of Rubiscos that existed billions of years ago. The ancient proteins were brought back to life in the lab by the researchers. The scientists were wondering if Rubisco's new component had anything to do with higher specificity.
The new component was supposed to exclude oxygen from the Rubisco catalytic center. It's not what happened. The effect on Rubisco's catalytic subunit was changed by the recruitment of the subunit. The new component had a big effect on specificity. Rubisco's evolutionary potential was completely changed by the introduction of this new subunit.
An animal's addiction to something.
Even though other forms of Rubisco can function without this function, it is still dependent on it, even though other forms can function without it. When Rubisco is bound to this small component, it becomes tolerant of all the bad things that could happen. Rubisco became addicted to its new subunit, as a result of the accumulating of such genes.
Since it encountered the new component, Rubisco kept it. The importance of evolutionary analysis is highlighted by the fact that this connection was not understood until now. Rubisco's history can teach us a lot about why they are the way they are. We don't know much about the evolutionary history of many biochemical phenomena. The entire history of the cell is still waiting to be discovered, so it's exciting to be an evolutionary biochemist.
Insights for the future can be provided by scientific journeys back in time.
The study shows that traditional attempts to improve Rubisco may have been looking in the wrong place. Adding entirely new components to the enzyme could be more productive, according to our research. This is a completely new area for engineering.
More information: Luca Schulz et al, Evolution of increased complexity and specificity at the dawn of form I Rubiscos, Science (2022). DOI: 10.1126/science.abq1416 Journal information: Science
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