![Distribution and protein structures of ancestral energy conservation enzymes in bacteria and archaea. For escape as free-living cells, metabolism had to achieve the state of a balanced stoichiometric reaction145, called redox balance in physiology, and the exergonic reactions of electron transfer from H2 to CO2 needed to be coupled to the pumping of ions from the inside of the cell to the outside (chemiosmotic coupling), as in modern cells. Prior to the coupling of CO2 reduction to ion pumping, the natural pH gradient provided by serpentinizing systems (pH 9–11, vs. sea water (pH 6.5146) was harnessable with the help of simple, abiotically synthesized hydrophobics147,148 such as fatty acids, which were recently shown to support the ATP-synthesizing function of a rotor-stator ATPase149. -- [q-bio.PE]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Intermediate.png?resize=1200%2C721&ssl=1)
[q-bio.PE] The origin of life required the emergence of metabolism, an autocatalytic network of enzymatic reactions that synthesize amino acids, nucleotides and cofactors. At the origin of metabolism there were […]
Biochemistry & Organic Chemistry
Posted inAstronomy & Telescopes
Astrochemistry In Action: JWST View Of The Carina Nebula
[ESA] This NASA/ESA/CSA James Webb Space Telescope Picture of the Month takes us to a fantastical realm within our home galaxy, where piercing starlight and billowing winds sculpt dust clouds […]
![Bold black letters illustrate amino acids that are deduced as early by the approach, while red letters indicate late additions to the alphabet according to the approach (C* implies possible prebiotic synthesis under specific and narrow conditions [4]). Regular black letters represent amino acids that have not been resolved as either early or late by the approach. LUCA: last universal common ancestor; LECA: last eukaryotic common ancestor; rTCA: tricarboxylic acid cycle. -- Trends in Genetics](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Reconstructing.png?resize=1200%2C720&ssl=1)
Posted inGenomics, Proteomics, Bioinformatics
Reconstructing Ancient Protein Alphabets: What Can We Truly Infer?
[Trends in Genetics] The canonical amino acid alphabet has remained remarkably stable since life’s early stages, yet the factors that shaped its emergence remain debated. Early views emphasized prebiotic availability […]
![Herschel H2 column density map (Sadavoy et al. 2012) of Perseus starless and prestellar cores. Labeled in magenta are the locations and names of the 15 starless and prestellar cores analyzed. The star-forming regions within Perseus are denoted in black.-- [astro-ph.GA]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Inventories.png?resize=1200%2C716&ssl=1)
Posted inAstrochemistry
Inventories of Rich Carbon-Chain Chemistry in Prestellar and Starless Cores in the Perseus Molecular Cloud
[astro-ph.GA] Carbon-chain molecules serve as an important reservoir of reactive organic matter that will eventually be incorporated into protoplanetary disks, planets, and cometary material. Prestellar and starless cores are composed […]
Posted inOrigin & Evolution of Life
Two Origins Of Life
[Heinrich-Heine University Duesseldorf] How and where did the first forms of life arise? These are the main questions driving research at the Institute of Molecular Evolution at Heinrich Heine University […]
![Proposed reaction network for the radiolysis of PCN:N2 ice by 40 MeV 40Ar9+ ions at 10 K. The scheme summarizes the main fragmentation, radical recombination, isomerization, and nitrogen incorporation pathways inferred from the infrared identifications and kinetic analysis. The radicals shown in the "Primary fragmentation" box are representative examples of how reactive intermediates are inferred from the experimental results and do not constitute an exhaustive list of all fragments produced during irradiation. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Formation.png?resize=1200%2C706&ssl=1)
Posted inAstrochemistry
Formation Of Nitriles And Isonitriles By The Heavy-ion Irradiation Of Propionitrile In N2-rich Astrophysical Ices
[astro-ph.EP] Context. Nitriles are key nitrogen-bearing organic molecules in dense clouds, star-forming regions, and nitrogen-rich icy environments. Understanding their stability and chemical evolution under energetic processing is essential for understanding […]
![Time evolution for two morphological dynamics in PISA specimens: (a) gelation takes place in an oxygen-poor PISA specimen, (b) “Phoenix” dynamics take place in the oxygen-rich PISA specimen (Adapted with permission from reference [19]).-- [Life]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Degradation.png?resize=1200%2C718&ssl=1)
Posted inOrigin & Evolution of Life
Degradation, Osmosis and the Emergence of Basic Functionalities in Abiotic Synthetic Life-like Chemical Systems
[Life] Autonomous and interconnected multiscale out-of-equilibrium processes, including chemical and physical feedbacks, occur at the micron and lower scales during the heterotrophic synthesis of simple abiotic protocells, such as the […]
![Representation of the functional cycle (Funktionskreis) capturing the structural coherence between the living system and the assimilated environment, showing the analog coding processes operating in perception of external signals and in signal transduction, and the digital coding processes operating in the system's self-maintenance and reproduction. -- [BioSystems]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Codepoietic.png?resize=1200%2C716&ssl=1)
Posted inBiochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life
Codepoietic Biological Evolution: From The Origin Of Life To Eukaryogenesis
[BioSystems]. Evolution is an intrinsic property of autopoietic systems performing natural computation, which is based on an internal formal self-description representing the arrangement of digital and analog coding structures.
![Schematic illustration of the non-spatial Hash Chemistry model (from [16], with modification). - -[q-bio.PE]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Hash-Chemistry.png?resize=1200%2C717&ssl=1)
Posted inOrigin & Evolution of Life
Hash Chemistry: Minimal Models for Evolutionary Growth of Complexity
[q-bio.PE] Hash Chemistry is a family of minimalistic evolutionary models in which a deterministic hash function assigns a scalar score to entities of arbitrary size, opening a combinatorially vast possibility […]
Posted inComets and Asteroids
A JWST Study of Stardust. I. Infrared Spectroscopy of Comet 81P/Wild 2 and Overall Composition
[astro-ph.EP] We report observations of comet 81P/Wild 2, target of the Stardust sample return mission, on UT 2023 March 20 and 24 at a heliocentric distance (rH) of 1.85 au […]