Brandeis explores origins of life with $1 million Keck Foundation grant

Researchers tackle chemistry’s grand question

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Life is comprised of infinitely complex reactions and structures, yet it evolved from simple, non-living molecules. How? This is chemistry’s grand question.

Brandeis University scientists hope to shed light on this mystery with the help of a three-year, $1 million grant from the W.M. Keck Foundation to explore the chemical origins of life.

Chemists Irv Epstein, Li Deng, Bing Xu and physicist Michael Hagan will research key steps in the transition from simple molecules to life on Earth. 

They’re not the first to attempt to answer the grand question. Sixty years ago, University of Chicago chemists Stanley Miller and Harold Urey determined that a small group of simple molecules, such as water, methane and ammonia, could react to produce more complex molecules such as amino acids and sugars. Similarly, more recent studies have shown that much more complicated molecules such as nucleic acids can react to start building complex, cell-like structures. 

But what transpired between the formation of simple amino acids and complicated nucleic acids is still a mystery. Brandeis researchers will focus on that gap in life’s timeline. 

“We are not looking to answer the question, ‘How did life definitively evolve on Earth?’” Epstein says. “Rather, we are exploring possible avenues of how life could emerge from non-living matter.”

The team will focus on the evolution of molecular catalysts that are both autocatalytic, meaning they can react to produce more of themselves, and capable of self-organization, meaning they can spontaneously arrange themselves in intricate patterns by utilizing energy from their surroundings. These two qualities lead to more complex reactions and more complex structures — the key components for the development of life. 

The researchers will study these molecules in extremely hot, cold and acid environments — similar to the conditions they would have reacted in 3.8 billion years ago. These extreme conditions would likely have increased the types and complexities of reactions that these molecules undergo. 

This research will not only fill gaps in our understanding of how non-living matter laid the foundation for life, but also answer some of science’s nagging mysteries. For example, why do all amino acids found in living systems have the same chirality, or handedness, when nature is perfectly capable of producing either left or right chirality? 

“We are hoping to explore how these motifs we see all around us today could arise. For example, could a small fluctuation in the abundance of left-handed amino acids in an early, pre-biologic system take over to yield the exclusively left-handed proteins found in present-day biology,” Hagan says. “We’ll never know for sure what happened back then, but this research will help us understand what could have happened.”