Roughly 4 billion years ago, Earth was developing conditions suitable for life. Origin-of-life scientists often wonder if the type of chemistry found on the early Earth was similar to what […]
prebiotic
Posted inBiochemistry & Organic Chemistry, Biophysics, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life, Status Report
Constraints On The Emergence Of RNA Through Non-Templated Primer Extension With Mixtures Of Potentially Prebiotic Nucleotides
The emergence of RNA on the early Earth is likely to have been influenced by a series of chemical and physical processes that acted to filter out various alternative nucleic […]
Posted inBiochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life, Status Report
From the RNA-Peptide World: Prebiotic Reaction Conditions Compatible with Lipid Membranes for the Formation of Lipophilic Random Peptides in the Presence of Short Oligonucleotides, and More
Deciphering the origins of life on a molecular level includes unravelling the numerous interactions that could occur between the most important biomolecules being the lipids, peptides and nucleotides. They were […]
![A) Alanine synthesis using a Strecker mechanism, where the wiggly bonds indicate indeterminate stereochemistry. (B) Illustrating a calcium-promoted step on the reaction pathway where a PNC effect from Ca2+ could influence chiral preference at the Cα carbon (highlighted by circling in dashed blue). (C) An example of an Ala-bound calcium complex in a metal-mediated autocatalytic pathway, where L and L′ could be water, a bifurcating carboxylate from another amino acid [5], or other ligands. -- Life](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/01/Influence-of-the.png?resize=1200%2C900&ssl=1)
Posted inAstrochemistry, Biochemistry & Organic Chemistry, Biophysics, Origin & Evolution of Life, Status Report
Influence of the Weak Nuclear Force on Metal-Promoted Autocatalytic Strecker Synthesis of Amino Acids: Formation of a Chiral Pool of Precursors for Prebiotic Peptide and Protein Synthesis
Natural chiral amino acids typically adopt an L structural configuration. While a preference for specific molecular chiralities is observed throughout biology and cellular chemistry, the origins of this preference are […]
Posted inAstrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Origin & Evolution of Life, Status Report
Gamma-Ray-Induced Amino Acid Formation During Aqueous Alteration in Small Bodies: The Effects of Compositions of Starting Solutions
Organic compounds, such as amino acids, are essential for the origin of life, and they may have been delivered to the prebiotic Earth from extra-terrestrial sources, such as carbonaceous chondrites.
Posted inAstrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Status Report
Detection And Chemical Modelling Of Complex Prebiotic Molecule Cyanamide In The Hot Molecular Core G31.41+0.31
In the interstellar medium (ISM), the complex prebiotic molecule cyanamide (NH2CN) plays a key role in producing adenine (C5H5N5), purines (C5H4N4), pyrimidines (C4H4N2), and other biomolecules via a series of […]
Posted inAstrochemistry, Status Report
The Role of Low-energy (< 20 eV) Secondary Electrons in the Extraterrestrial Synthesis of Prebiotic Molecules
We demonstrate for the first time that Galactic cosmic rays with energies as high as 1e10 eV can trigger a cascade of low-energy (< 20 eV) secondary electrons that could […]
Posted inAstrochemistry, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Meteorites & Asteroids, Origin & Evolution of Life, Panspermia, Status Report
Prebiotic Syntheses of Organophosphorus Compounds from Reduced Source of Phosphorus in Non-Aqueous Solvents
Reduced-oxidation-state phosphorus (reduced P, hereafter) compounds were likely available on the early Earth via meteorites or through various geologic processes.
Posted inBiochemistry & Organic Chemistry, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life, Status Report
Triplet-Encoded Prebiotic RNA Aminoacylation
The encoding step of translation involves attachment of amino acids to cognate tRNAs by aminoacyl-tRNA synthetases, themselves the product of coded peptide synthesis. So, the question arises─before these enzymes evolved, […]
![Simulated nicotinic acid abundances compared to measured values in carbonaceous chondrites and asteroid (162173) Ryugu. A rock density of 3 g cm−3 , a porosity of 0.2, [56–58] and an ice density of 0.917 g cm−3 completely filling the pores (after all radionuclides have decayed and aqueous activity has ceased) were assumed as the properties of the planetesimal/carbonaceous chondrite hosting the chemical synthesis. The simulations were run at a pressure of 100 bar. From left to right, the plotted bars show the simulated molecular abundance of nicotinic acid (solid black line on the very left) for the whole temperature range of liquid water, as well as the abundances measured in samples of Cb asteroid (162173) Ryugu collected during the Hayabusa2 spacecraft mission, [14] in the CI chondrite Orgeil, [14] several Antarctic CM2 chondrites, [12] the CM2 chondrites Murchison and Murray, and the ungrouped C2 chondrite Tagish Lake [13] as lines and shaded ranges described in the legend. Each time, the measured nicotinic acid abundance and the sum of all isomers (nicotinic acid, isonicotinic acid, picolinic acid) are given, since thermochemical equilibrium simulations cannot distinguish between isomers. The type of extraction method used (hot water, cold water ultrasonication, HCl-hydrolyzed, formic acid) is denoted next to each panel. A tabulated version of the data presented here is available in the Supporting Information in Table S1. -- astro-ph.EP](https://i0.wp.com/astrobiology.com/wp-content/uploads/2023/10/prebiotic.png?resize=1200%2C720&ssl=1)
Posted inAstrochemistry, Biochemistry & Organic Chemistry, Comets and Asteroids, Genomics, Proteomics, Bioinformatics, Imaging & Spectroscopy, Meteorites & Asteroids, Origin & Evolution of Life, Status Report
Prebiotic Vitamin B3 Synthesis In Carbonaceous Planetesimals
Aqueous chemistry within carbonaceous planetesimals is promising for synthesizing prebiotic organic matter essential to all life.