Any hypothesis involving the origin of life must include the prebiotic origin of the protocell. While phospholipid vesicles have been well studied, how fatty acid-based vesicles emerge remains to be determined.
A recent Scripps study provides a possible explanation for how protocells originally evolved and then chemically developed to accomplish a variety of tasks.
According to the study, phosphorylation – a chemical process by which a molecule receives a phosphate group – may have originated much earlier. This results in more structurally complex, double-stranded protocytes with a wide range of functions to support chemical reactions and**. By revealing the process of the formation of protocells, scientists can better understand how early evolution occurred.
This study could provide a better understanding of the chemical environment of the early Earth to reveal the origin of life and how life evolved on early Earth.
In this study, scientists looked at the chemical processes that produced basic substances and structures on primitive Earth before life began to evolve. They then investigated the possibility that phosphate plays a role in the development of protocells. Since phosphates are involved in almost all bodily chemical reactions, Krishnamurthy speculates that their existence may be older than previously thought.
Previously, scientists thought that fatty acids produce protocytes; However, it is unclear how the primary cells switch from single-stranded phosphate to double-stranded phosphate.
To be sure, the scientists wanted to simulate reasonable prebiotic conditions. They first identified a mixture of three chemicals that could produce vesicles, a spherical lipid structure similar to a primary cell.
Fatty acids and glycerin, a typical by-product of soap manufacturing, may have been present in the early history of the Earth and are among the compounds used. They then add other chemicals to make new mixtures while observing the reaction of those mixtures. These solutions are repeatedly heated and cooled throughout the overnight shaking process to facilitate the chemical reaction.
After that, they used a fluorescent dye to check the mixture to see if vesicle formation had occurred. Scientists occasionally change the pH and component ratios to learn more about how these variables affect vesicle formation. They also studied how temperature and metal ions affect the stability of vesicles.
"In our experiments, vesicles were able to transition from a fatty acid environment to a phospholipid environment, suggesting that a similar chemical environment may have existed 4 billion years ago," said Sunil, a postdoctoral researcher at Krishnamurti's lab. ”
A more stable double-stranded structure may be formed by phosphorylation of fatty acids and glycerol. Specifically, fatty acid esters formed from glycerol may have produced vesicles with different sensitivities to pH, temperature, and metal ions – a critical step in diversification evolution.
"It's exciting to reveal how early chemicals transformed into life on Earth," Denitz said. Our findings also hint at a wealth of interesting physical phenomena that may play a key functional role in modern cells. ”