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The Metabolism-First hypothesis for the origin of life posits that organic chemical reaction networks originated in geochemistry and became more complex through catalytic feedback effects. This process would lead to increasing autonomy from the original environment, ultimately resulting in the metabolic pathways found in chemoautotrophic organisms and a free-standing cell replete with catalysts for its own reactions (coenzymes, enzymes and genes). This hypothesis connects well with early microbial physiology – a weakness of other hypotheses.

But what lowered the kinetic barriers such that these reaction networks could have emerged in the first place? Heterogeneous catalysis by metals and minerals was long suspected, but extensive experimental work from my group and others has shown them to be promising yet insufficient. What is missing?

Here I propose that strong electric fields, working together with metals, were life’s first catalysts. Electric field catalysis is exceptionally general, maximizing the chance that complex reaction networks can emerge. An origin of metabolism under electric fields explains why enzymes operate predominantly by electrostatic effects, why phosphorylation is so central to metabolism despite being so challenging in water, and provides a fresh take on how proton gradients, catalysis, and phosphorylation became linked in membrane bioenergetics. Experiments and calculations supporting this hypothesis will be presented.

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Bio:

A native of Rosemère, QC, Joseph completed his B.Sc. and Ph.D. in synthetic organic chemistry at the University of Ottawa before moving to the University of Texas at Austin for postdoctoral work. In 2012, he joined ISIS/University of Strasbourg as an assistant professor and was promoted directly to full professor in 2018. In Strasbourg, he was a two-time ERC grantee and was made a member of the Institut Universitaire de France. In 2024, he returned to the University of Ottawa as a Tier 1 Canada Research Chair. His research interests are in organic chemistry, the origin of life, and how vibrational strong coupling can influence chemistry. He was awarded the Liebig Lectureship from the German Chemical Society (2022), the Forcheurs Jean-Marie Lehn Prize (2020, with Harun Tüysüz), C&EN’s Talented 12 (2018), and the Jean Normant Prize from the French Chemical Society (2018).