The origin of life: Oligomerization of RNA nucleotides on prebiotic Earth

We propose a plausible oligomerization process of RNA nucleotides on prebiotic Earth. The process takes place at tideland and estuary where wet & dry cycle and pH fluctuation occur due to tide. The process proceeds with help of clay minerals that catalyze not only oligomerization but also cross complementary self-replication of RNA oligomers by lowering the activation energy of covalent bonding. The self-replication realizes transfer of molecular information and allows mutation and natural selection, essential steps of evolution of life.

A graphene oxide coated tapered microfiber acting as a super-sensor for rapid detection of SARS-CoV-2

COVID-19 is a new strain of highly contagious coronavirus. Now, an innovative approach to detect it by combining DNA/RNA oligomers as aptamers and a GO coated optical microfiber as a sensor system.

Harnessing Chemical Energy for the Activation and Joining of Prebiotic Building Blocks

Simultaneous activation of carboxylates and phosphates provides multiple pathways for the generation of reactive intermediates, including mixed carboxylic acid-phosphoric acid anhydrides, for the synthesis of peptidyl-RNAs, peptides, RNA oligomers and primordial phospholipids. These results indicate that unified prebiotic activation chemistry could have enabled the joining of building blocks in aqueous solution from a common pool and enabled the progression of a system towards higher complexity foreshadowing the modern encapsulated peptide-nucleic acid system

Harnessing Chemical Energy for the Activation and Joining of Prebiotic Building Blocks

Simultaneous activation of carboxylates and phosphates provides multiple pathways for the generation of reactive intermediates, including mixed carboxylic acid-phosphoric acid anhydrides, for the synthesis of peptidyl-RNAs, peptides, RNA oligomers and primordial phospholipids. These results indicate that unified prebiotic activation chemistry could have enabled the joining of building blocks in aqueous solution from a common pool and enabled the progression of a system towards higher complexity foreshadowing the modern encapsulated peptide-nucleic acid systemThis paper has been accepted by Nature Chemistry<div>https://www.nature.com/articles/s41557-020-00564-3<br></div>

Synthesis of oligonucleotides on a soluble support

Oligonucleotides are usually prepared in lab scale on a solid support with the aid of a fully automated synthesizer. Scaling up of the equipment has allowed industrial synthesis up to kilogram scale. In spite of this, solution-phase synthesis has received continuous interest, on one hand as a technique that could enable synthesis of even larger amounts and, on the other hand, as a gram scale laboratory synthesis without any special equipment. The synthesis on a soluble support has been regarded as an approach that could combine the advantageous features of both the solution and solid-phase syntheses. The critical step of this approach is the separation of the support-anchored oligonucleotide chain from the monomeric building block and other small molecular reagents and byproducts after each coupling, oxidation and deprotection step. The techniques applied so far include precipitation, extraction, chromatography and nanofiltration. As regards coupling, all conventional chemistries, viz. phosphoramidite, H-phosphonate and phosphotriester strategies, have been attempted. While P(III)-based phosphoramidite and H-phosphonate chemistries are almost exclusively used on a solid support, the “outdated” P(V)-based phosphotriester chemistry still offers one major advantage for the synthesis on a soluble support; the omission of the oxidation step simplifies the coupling cycle. Several of protocols developed for the soluble-supported synthesis allow the preparation of both DNA and RNA oligomers of limited length in gram scale without any special equipment, being evidently of interest for research groups that need oligonucleotides in large amounts for research purposes. However, none of them has really tested at such a scale that the feasibility of their industrial use could be critically judged.

Post-synthetic conversion of 5-pivaloyloxymethyluridine present in a support-bound RNA oligomer into biologically relevant derivatives of 5-methyluridine

A reliable post-synthetic method to access the modified RNA oligomers containing biologically important 5-methyluridines: mnm5U, cmnm5U, τm5U, nm5U, inm5U and cnm5U.