Sticky beginnings: When life began to gel

How did life begin? An international team of researchers from Japan, Malaysia, the UK, and Germany suggest that the answer may lie in sticky, surface-bound gels that existed long before the first cells.

Their insights offer a new lens for both understanding life’s origins on Earth and recognizing the possibility of life elsewhere.

The study was published online in ChemSystemsChem on Nov. 19 and will appear in an upcoming print issue.

The question of how life began has puzzled humanity for centuries. Whilst no one can travel back in time to witness the first spark of life, scientists continue to piece together plausible stories from chemistry, physics and geology.

“While many theories focus on the function of biomolecules and biopolymers, our theory instead incorporates the role of gels at the origins of life,” said Tony Z. Jia, professor at Hiroshima University and co-lead author of the paper.

In their newly proposed “prebiotic gel-first” framework, the researchers suggest how life could have originated within surface-attached gel matrices—sticky, semi-solid materials that share properties with today’s microbial biofilms, the thin layers of bacteria that grow ubiquitously on rocks, pond surfaces, and even man-made objects.

Drawing from soft-matter chemistry and insights from modern biology, the study argues that such primitive gels could have provided the necessary structure and function for early chemical systems to become increasingly complex, long before the first cells emerged.

By trapping and organizing molecules, prebiotic gels may have overcome key barriers in pre-life chemistry through allowing for molecular concentration, selective retention, and environmental buffering. Within these gels, early chemical systems might have developed proto-metabolic and self-replicating behaviors, setting the stage for biological evolution.

“This is just one theory among many in the vast landscape of origin-of-life research,” said Kuhan Chandru, research scientist at the Space Science Center, National University of Malaysia (UKM) and co-lead author of the study. “However, since the role of gels has been largely overlooked, we wanted to synthesize scattered studies into a cohesive narrative that puts primitive gels at the forefront of the discussion.”

The researchers also extend this idea to astrobiology, suggesting that similar gel-like systems might exist on other planets. These potential “Xeno-films” could be non-terrestrial analogs of biofilms, composed of different chemical building blocks uniquely available at each locale. This perspective broadens the scope of how scientists search for life beyond Earth by suggesting that perhaps structures, rather than specific chemicals, could be the next target for life detection missions.

The team plans to investigate their model experimentally by exploring how such gels, composed of simple chemicals, might have formed in early Earth conditions and what properties these gels could have provided to emerging chemical systems.

“We also hope that our work inspires others in the field to further explore this and other underexplored origins-of-life theories!” said Ramona Khanum, co-first author of the paper and a former intern at UKM.

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The University of Leeds Research Mobility Funding, the Alexander von Humboldt Foundation, the Japan Society for the Promotion of Science, and the Mizuho Foundation for the Promotion of Science supported this work.

About Hiroshima University

Since its foundation in 1949, Hiroshima University has striven to become one of the most prominent and comprehensive universities in Japan for the promotion and development of scholarship and education. Consisting of 12 schools for undergraduate level and 5 graduate schools, ranging from natural sciences to humanities and social sciences, the university has grown into one of the most distinguished comprehensive research universities in Japan. English website: https://www.hiroshima-u.ac.jp/en