Novel Formulations for the Genesis of Life: Paving the Way for the Discovery of Extraterrestrial Existence

Novel Formulations for the Genesis of Life: Paving the Way for the Discovery of Extraterrestrial Existence

Life is fundamentally dependent on recurring chemical interactions. Understanding the nature and prerequisites of these self-perpetuating reactions—referred to as autocatalysis—may sharpen the focus on the quest for extraterrestrial life. Attribution: Betül Kaçar

A group spearheaded by researchers has capitalized on the finite scope of chemical pairings to assemble a compendium comprising numerous formulae that could potentially be the building blocks of life.

The characteristics of life on a distant celestial body—should it exist—may bear little resemblance to terrestrial life forms. Nevertheless, the cosmic inventory of chemical constituents is limited, as are the ways in which they can be combined. A research team led by scholars at the University of Wisconsin–Madison has harnessed these constraints to develop a compendium filled with various chemical formulae that could serve as precursors to life.

This compilation could steer the search for life in the cosmos by identifying the most plausible conditions—akin to terrestrial mixing methods, heat settings, and cooking durations—under which these formulae could coalesce.

Progression from rudimentary chemical constituents to intricate cycles of cellular metabolism and procreation, according to the researchers, necessitates both a basic starting point and ongoing repetition.

“Life’s inception is fundamentally a process of emergence from nothingness,” states Betül Kaçar, an astrobiologist funded by NASA and a professor of bacteriology at the University of Wisconsin–Madison. “Yet this initial emergence must be perpetuated. Life boils down to specific chemistry and circumstances that can maintain a continuous loop of reactions.”

The Underpinnings of Chemical Interactions

Autocatalytic reactions are those that produce molecules that, in turn, facilitate the same reaction to occur repeatedly. In a recent study published on September 18 in the Journal of the American Chemical Society, Zhen Peng, a postdoctoral fellow in the Kaçar laboratory, along with his colleagues, identified 270 molecular combinations—incorporating elements from diverse groups and series of the periodic table—capable of sustained autocatalysis.

“The conventional wisdom was that such reactions are exceedingly scarce,” Kaçar notes. “Our findings challenge that notion, suggesting that these reactions are far from being limited if one knows where to look.”

The researchers concentrated on a specific class of reactions known as comproportionation reactions. In these processes, two compounds containing the same element but in different electron states amalgamate to produce a new compound featuring the element in an intermediate state between the initial reactive states.

For a reaction to be classified as autocatalytic, its end product must also serve as a substrate for the recurrence of the reaction, explains Zach Adam, a co-author of the study and a geoscientist at the University of Wisconsin–Madison specializing in the origins of life. Comproportionation reactions lead to the generation of multiple instances of some of the participating molecules, thus providing the raw materials for subsequent autocatalytic steps.

“Under the right circumstances, a limited number of these products can suffice,” Adam says. “Each cycle results in the production of additional molecules that expedite the reaction, thus amplifying it further.”

Future Research Directions and Implications

Searching for recognizable biological features in the cosmos might not be an effective approach. Instead, Kaçar envisions that chemists will utilize the new compendium’s formulas as a basis for experiments simulating extraterrestrial conditions.

“Though it’s impossible to know the exact conditions that led to life on Earth, controlled experiments can create diverse planetary settings to examine how the mechanisms to sustain life may originate,” Kaçar comments.

Kaçar directs a NASA-funded consortium named MUSE, which stands for Metal Utilization & Selection Across Eons. Her laboratory plans to concentrate on reactions involving elements such as molybdenum and iron. She is eager to observe what novel discoveries may arise from the exploration of the compendium’s more unconventional and rare entries.

“As Carl Sagan articulated, to create a pie from scratch, one must first invent the universe,” says Kaçar. “In a similar vein, if we aim to comprehend the cosmos, it’s essential that we first experiment with various formulae.”

Acknowledgments

The research received financial support from various entities including the NASA Astrobiology Program (80NSSC22K0546), the John Templeton Foundation (62578 and 61926), the Research Corporation for Science Advancement (28788), and the Australian Research Council (DP210102133 and FT220100757).

Reference: “Assessment of Stoichiometric Autocatalysis across Element Groups” by Zhen Peng, Zachary R. Adam, Albert C. Fahrenbach and Betül Kaçar, 18 September 2023, Journal of the American Chemical Society.
DOI: 10.1021/jacs.3c07041

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More about Extraterrestrial Life Origins

• Journal of the American Chemical Society
• NASA Astrobiology Program
• University of Wisconsin–Madison
• John Templeton Foundation
• Research Corporation for Science Advancement
• Australian Research Council
• Betül Kaçar’s Professional Profile
• Chemical Autocatalysis
• MUSE Consortium
• Cosmic Chemistry and Origins of Life