Accumulation and selection of nucleotides is one of the most challenging problems surrounding the origin of the first RNA molecules on our planet. In the current work we propose that guanosine 3',5' cyclic monophosphate could selectively crystallize upon evaporation of an acidic prebiotic pool containing various other nucleotides. The conditions of the evaporative crystallization are fully compatible with the subsequent acid catalyzed polymerization of this cyclic nucleotide reported in earlier studies and may be relevant in a broad range of possible prebiotic environments. Albeit cytidine 3',5' cyclic monophosphate has the ability to selectively accumulate under the same conditions, its crystal structure is not likely to support polymer formation.

• Klíčová slova
• Biochemistry, Biological sciences, Natural sciences,
• Publikační typ
• časopisecké články MeSH

The assembly of ancient informational polymers from nucleotide precursors is the central challenge of life's origin on our planet. Among the possible solutions, dry polymerization of 3',5'-cyclic guanosine monophosphate (3',5'-cGMP) has been proposed as a candidate to create oligonucleotides of 15-20 units in length. However, the reported sensitivity of the reaction to the presence of cations raised questions of whether this chemistry could be relevant in a geological context. The experiments in this study show that the presence of cations is not restrictive as long as the reaction is conducted in an acidic environment, in contrast to previous reports that suggested optimal conditions at pH 9.

• Klíčová slova
• cGMP, nonenzymatic polymerization, nucleotides, prebiotic chemistry,
• MeSH
• guanosinmonofosfát cyklický * MeSH
• katalýza MeSH
• oligonukleotidy MeSH
• polymerizace MeSH
• RNA * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• guanosinmonofosfát cyklický * MeSH
• oligonukleotidy MeSH
• RNA * MeSH

Template-free nonenzymatic polymerization of 3',5' cyclic nucleotides is an emerging topic of the origin of life research. In the last ten years, a number of papers have been published addressing various aspects of this process. These works evoked a vivid discussion among scientists working in the field of prebiotic chemistry. The aim of the current review is to answer the most frequently raised questions related to the detection and characterization of oligomeric products as well as to the geological context of this chemistry.

• Klíčová slova
• cyclic nucleotides, polymerization, prebiotic chemistry,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Molecular Darwinian evolution is an intrinsic property of reacting pools of molecules resulting in the adaptation of the system to changing conditions. It has no a priori aim. From the point of view of the origin of life, Darwinian selection behavior, when spontaneously emerging in the ensembles of molecules composing prebiotic pools, initiates subsequent evolution of increasingly complex and innovative chemical information. On the conservation side, it is a posteriori observed that numerous biological processes are based on prebiotically promptly made compounds, as proposed by the concept of Chemomimesis. Molecular Darwinian evolution and Chemomimesis are principles acting in balanced cooperation in the frame of Systems Chemistry. The one-pot synthesis of nucleosides in radical chemistry conditions is possibly a telling example of the operation of these principles. Other indications of similar cases of molecular evolution can be found among biogenic processes.

• Klíčová slova
• Chemomimesis, Molecular Darwinism, origin of life, systems chemistry,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

A short history of Campbell's primordial soup: In this essay we try to disclose some of the historical connections between the studies that have contributed to our current understanding of the emergence of catalytic RNA molecules and their components from an inanimate matter.

• Klíčová slova
• RNA, nucleosides, nucleotides, oligonucleotides, prebiotic chemistry,
• MeSH
• nukleosidy chemie   MeSH
• nukleotidy chemie   MeSH
• prebiotika * MeSH
• ribozomy metabolismus   MeSH
• RNA katalytická metabolismus   MeSH
• RNA metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• nukleosidy MeSH
• nukleotidy MeSH
• prebiotika * MeSH
• RNA katalytická MeSH
• RNA MeSH

Recent studies illustrate that short oligonucleotide sequences can be easily produced from nucleotide precursors in a template-free non-enzymatic way under dehydrating conditions, i.e. using essentially dry materials. Here we report that 3',5' cyclic AMP may also serve as a substrate of the reaction, which proceeds under moderate conditions yet with a lower efficiency than the previously reported oligomerization of 3',5' cyclic GMP. Optimally the oligomerization requires (i) a temperature of 80°C, (ii) a neutral to alkaline environment and (iii) a time on the order of weeks. Differences in the yield and required reaction conditions of the oligomerizations utilizing 3',5' cGMP and cAMP are discussed in terms of the crystal structures of the compounds. Polymerization of 3',5' cyclic nucleotides, whose paramount relevance in a prebiotic chemistry context has been widely accepted for decades, supports the possibility that the origin of extant genetic materials might have followed a direct uninterrupted path since its very beginning, starting from non-elaborately pre-activated monomer compounds and simple reactions.

• MeSH
• guanosinmonofosfát cyklický chemie   MeSH
• kinetika MeSH
• koncentrace vodíkových iontů MeSH
• polymerizace * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• guanosinmonofosfát cyklický MeSH

Emergence of the very first RNA or RNA-like oligomers from simple nucleotide precursors is one of the most intriguing questions of the origin of life research. In the current paper, we analyse the mechanism of four non-enzymatic template-free scenarios suggested for the oligomerization of chemically non-modified cyclic and acyclic nucleotides in the literature. We show that amines may have a twofold role in these syntheses: due to their high affinity to bind protons they may activate the phosphorus of the phosphate group via proton transfer reactions, or indirectly they may serve as charge compensating species and influence the self-assembling of nucleotides to supramolecular architectures compatible with the oligomerization reactions. Effect of cations and pH on the reactions is also discussed.

• Klíčová slova
• Oligonucleotides, Origin of life, Polymerization, RNA,
• MeSH
• molekulární evoluce * MeSH
• nukleotidy metabolismus   MeSH
• oligonukleotidy biosyntéza   MeSH
• původ života * MeSH
• RNA * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• nukleotidy MeSH
• oligonukleotidy MeSH
• RNA * MeSH