Abstract:
The complexity of modern biochemistry suggests that a systems chemistry approach is required to understand and potentially recapitulate the intricate network of prebiotic reactions that led to the emergence of life. Early cells probably relied upon compatible and interconnected chemistries to link RNA, peptides and membranes. In this context, understanding how and when phospholipid membranes appeared on early Earth is critical to elucidating the prebiotic pathways that led to the emergence of primitive cells. Starting with a mixture of activated carboxylic acids of different lengths, iterative cycling of acylation and hydrolysis steps allowed for the selection of longer-chain acylglycerol-phosphates through accumulation-induced compartmentalization of self-assembling amphiphiles at the expense of non-self-assembling shorter chain analogues. Our results suggest that a selection pathway based on energy-dissipative cycling could have driven the selective synthesis of phospholipids on the early Earth. Moreover, I will show that several types of vesicles, formed from prebiotically plausible mixtures of amphiphiles, allow activation of amino acids, peptides and nucleotides. Interestingly, activation chemistry drives the advantageous conversion of reactive amphiphiles into inert cyclophospholipids, thus supporting their potential role as major constituents of primitive cells. Activation of prebiotic building blocks within fatty acid-based vesicles yields lipidated species capable of localizing and functionalizing primitive membranes. Our findings describe a potentially prebiotic network of reactions in which the components of primitive cells could have selectively undergone activation and reacted to yield new species, which enabled the emergence of cells with increasingly advanced functionalities.

Speaker: Dr. Claudia Bonfio, Marie Skłodowska-Curie European Fellow, MRC Laboratory of Molecular Biology, Cambridge (UK)

Speaker bio: Claudia is a Marie Curie Fellow at the MRC Laboratory of Molecular Biology and a Junior Research Fellow in Biological Sciences at Corpus Christi College at the University of Cambridge (UK), working on prebiotic chemistry and non-enzymatic RNA replication within primordial cells. During her PhD in Biochemistry in the group of Prof. Sheref Mansy at the University of Trento (IT), she spent 3 months at Harvard University studying the astrochemistry taking place on early Earth and the emergence of primordial cells. Among other national and international awards, she received the Dalton Emerging Researcher Award (given by the Royal Society of Chemistry) and she was listed by Forbes Italy among the 100 under 30 future Italian leaders (in the Science category).

ELSI Host: Tony Jia

Date: Fri, 12 June 2020 at 15:30-16:30 JST (Fri, 12 June 2020 at 06:30-07:30 UTC)

Venue: Online