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Phosphorylation of (pre)biological molecules in water has been a long-sought goal in prebiotic chemistry. Now, it has been demonstrated that diamidophosphate phosphorylates nucleosides, amino acids and glycerol/fatty acids in aqueous medium, while simultaneously leading to higher-order structures such as oligonucleotides, peptides and liposomes in the same reaction mixture.

The citric acid cycle (TCA) is a fundamental metabolic pathway to release stored energy in living organisms. Here, the authors report two linked cycles of reactions that each oxidize glyoxylate into CO₂ and generate intermediates shared with the modern TCA cycle, shedding light into a plausible TCA protometabolism.

Structural biology, computational biology and biochemical analysis revealed the molecular mechanism of transcriptional processing of unnatural base pairs selectively recognized by cellular RNA polymerase.

Cooperative relationships are widespread among different classes of biopolymers and are predicted to have existed during emergence of life. This study shows that proto-peptides engage in mutually stabilizing interactions with RNA, providing support for the co-evolution of these molecules.

Systematic characterization of codons using the unnatural base pair dNaM·dTPT3 leads to the discovery of nine new functional codon–anticodon pairs, three of which are shown to be orthogonally decoded by ribosomes and allow incorporation of up to three noncanonical amino acids in Escherichia coli.

One of the questions for prebiotic chemistry is the formation of complementary base pairing systems. Here, the authors show that plausible two prebiotic heterocycles can form glycosidic bonds with ribose in water and that these spontaneously base-pair in aqueous solution.

The apparent disconnect between prebiotic aldehyde-based Strecker synthesis of amino acids and the α-ketoacid-based metabolism of extant biochemistry necessitates an evolutionary switch between these disparate chemistries. Now it has been shown that Bucherer–Bergs reactions of α-ketoacids produce α-amino acids and dihydroorotate, paralleling the biochemical synthesis of orotate and suggesting a more congruent evolutionary pathway from cyanide-based chemistries.

It’s unclear how protometabolic reactions emerged and evolved into extant metabolic pathways such as the tricarboxylic acid cycle. Now, it has been shown that cyanide acts as a mild and efficient reducing agent, mediating abiotic transformations of tricarboxylic acid intermediates and derivatives.

RNA is usually considered to be the first genetic polymer, with DNA a product of a biochemical pathway that arose after the origin of life. Now, studies into the prebiotic phosphorylation of an RNA nucleoside reveal pathways for the synthesis of DNA building blocks, providing experimental support for a prebiotic link between RNA and DNA.

The emergence of pristine RNA and DNA on the early Earth would have been hindered by a lack of specificity in their prebiotic syntheses. Now, it has been shown that chimeric sequences—with a mixture of RNA and DNA backbones—mediate the template-directed ligation of oligomers present in mixtures of nucleic acids, enabling the simultaneous appearance of RNA and DNA.

Metal-catalysed prebiotic reactions have been proposed as forerunners of modern metabolism. Now, an abiotic pathway resembling the reverse tricarboxylic acid cycle has been shown to proceed without metal catalysis. The reaction of glyoxylate and pyruvate produces a series of α-ketoacid tricarboxylic acid analogues, and provides a route to generate α-amino acids by transamination.

The challenge of the ‘Phosphate Problem’ in prebiotic chemistry limits the formation of key phosphorylating agents. Here, the authors demonstrate that ammonolysis of pyrophosphite yields amidophosphite, which oxidizes to monoamidophosphate, facilitating nucleotide formation from nucleosides.