Two UT Scientists Part of Project to Detect ‘Life As We Don’t Know It’

A nearly $7 million grant from NASA is supporting research to develop approaches to detecting extraterrestrial life, and two University of Texas at Austin faculty are part of the interdisciplinary scientific team.

The project's goal is to develop methods to detect life on other worlds that might look nothing like life on Earth. Eric Anslyn, a professor of chemistry, and Andrew Ellington, a professor of molecular biosciences, are the two UT Austin representatives on the team.

NASA's Astrobiology Program is seeking to develop new approaches to detecting life in places such as Mars, Jupiter and Saturn's icy moons through what's being called Laboratory for Agnostic Biosignatures (LAB). A team of investigators will lay the groundwork for characterizing potential biosignatures, or signs of life, that do not presuppose any particular molecular framework, as well as designing tools for their detection and strategies for interpretation.

"This project will help us perhaps answer the age-old question, 'What is life?'" Ellington said, "And the newer question, 'How will we know it when we see it on another planet?'"

LAB is a consortium that fosters collaborations among 15 planetary scientists, biologists, chemists, computer scientists, mathematicians and veteran instrument scientists, spanning 10 institutions around the world.

Life We Can Scarcely Imagine

"Our goal is to go beyond what we currently understand and devise ways to find forms of life we can scarcely imagine," says principal investigator Sarah Stewart Johnson of Georgetown University.

LAB's initial research focus is on four features of life that do not assume any specific biochemistry, and will branch out from these concepts to build a framework for looking for life "as we don't know it." These features include: patterns of chemical complexity, surface complexity, chemical disequilibrium with the surrounding environment, and evidence of energy transfer. These indicators of life were chosen since they can be framed in a way that doesn't bias observations toward the specific forms of life on Earth and are methods that could be implemented on flight missions. Pulling all of these concepts together, LAB also supports a computational team developing theoretical models to understand the full possibility space for life and a curation group responsible for selecting concept tests, benchmarking standards, and compiling results in a model that can be used to guide sample and instrument selection for future life detection missions.

LAB will be one of the teams in the Network for Life Detection, or NfoLD, a multi-institution research coordination network focused on developing technologies and techniques for life detection on other worlds. Following on decades of research supporting and expanding our understanding of habitability, the limits of life and habitable environments on other planets and moons, NfoLD will open the frontiers of research by catalyzing and connecting the life detection community, laying the groundwork for cutting-edge studies and allowing the quest for extraterrestrial life to venture into unexplored territories.

UT will receive over $722,000 over five years for the project, for which Anslyn and Ellington will be exploring a branch of chemistry known as chemometrics. The project blends information science with chemical analysis to identify patterns unique to given materials. The team will use NextGeneration DNA sequencing to read out chemical reactions, harnessing a powerful technology that has already revolutionized biomedical research. The result will be high-resolution chemical "fingerprints" of living and non-living materials, that the scientists will apply machine learning algorithms to in order to classify them.

"NASA's continuing explorations and missions are constantly facing the challenge that if life were to be discovered elsewhere, how would we know it?" Ellington said. "To answer this fundamental question requires the development of novel analytical methods that can potentially distinguish living from non-living materials."

Collaborative Synergy

The NASA grant is the third major award to Anslyn and Ellington in about the last year. In December 2017, the pair were chosen by the Howard Hughes Medical Institute as HHMI professors and awarded $1.5 million to support initiatives in undergraduate education.

Over the summer, they also secured a $400,000 grant from the prestigious iSuperSeed2 program through the National Science Foundation. As researchers in UT Austin's new Center for Dynamics and Control of Materials,part of the NSF's network of Materials Research in Science and Engineering Centers (MRSEC), the scientists were invited to apply for the funding. The NSF-funded project dovetails with the labs' chemometrics work on the NASA project, but does not overlap. For example, although both projects involve analyzing chemical samples sent from labs across the country that are indicative of chemicals associated with life-forms or not, the samples and the research goals differ, Anslyn said.

"The iSuperSeed2 project is oriented toward fingerprinting characteristics of various materials," he said. "We're looking at materials whose complexity could only be made by a lifeform."

For instance, snails and lobsters are organisms that, in forming their shells, make complex materials. Characterizing complex materials could aid in identifying and classifying entirely new complex chemicals and their associated assemblies in planets and moons outside the solar system.