Can polarity-inverted membranes self-assemble on Titan?
Journal article, 2020

The environmental and chemical limits of life are two of the most central questions in astrobiology. Our understanding of life’s boundaries has implications on the efficacy of biosignature identification in exoplanet atmospheres and in the solar system. The lipid bilayer membrane is one of the central prerequisites for life as we know it. Previous studies based on molecular dynamics simulations have suggested that polarity-inverted membranes, azotosomes, made up of small nitrogen-containing molecules, are kinetically persistent and may function on cryogenic liquid hydrocarbon worlds, such as Saturn’s moon Titan. We here take the next step and evaluate the thermodynamic viability of azotosome formation. Quantum mechanical calculations predict that azotosomes are not viable candidates for self-assembly akin to lipid bilayers in liquid water. We argue that cell membranes may be unnecessary for hypothetical astrobiology under stringent anhydrous and low-temperature conditions akin to those of Titan.



Molecular dynamics

Quantum theory


Hilda Sandström

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Martin Rahm

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Science advances

2375-2548 (eISSN)

Vol. 6 4 eaax0272

Subject Categories

Physical Chemistry


Theoretical Chemistry


C3SE (Chalmers Centre for Computational Science and Engineering)



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3/9/2021 7