Self-Sorting in Dynamic Combinatorial Libraries Leads to the Co-Existence of Foldamers and Self-Replicators

Nature segregates fundamental tasks such as information storage/transmission and catalysis between two different compound classes (e.g. polynucleotides for replication and folded polyamides for catalysis). This division of labor is likely a product of evolution, raising the question of how simpler systems in which replicators and folded macromolecules co-exist may emerge in the transition from chemistry to biology. In synthetic systems, achieving co-existence of replicators and foldamers in a single molecular network remains an unsolved problem. Previous work on dynamic molecular networks has given rise to either self-replicating fibers or well-defined foldamer structures (or completely un-sorted complex systems). We report a system in which two cross-reactive dithiol (nucleobase- and peptide-based) building blocks self-sort into a replicator fiber and foldamer that both emerge spontaneously and co-exist. The self-sorting behavior remains prevalent across different building block ratios as two phases of emergence occur: replicator growth followed by foldamer formation. This is attributed to the autocatalytic formation of the replicator fiber, followed by enrichment of the system in the remaining building block, which is subsequently incorporated into a foldamer

Selection of diverse polymorphic structures from a small dynamic molecular network controlled by the environment

The complex interplay between systems and their environment plays an important role in processes ranging from self-assembly to evolution. Polymorphism, where, from the same ingredients different products can be formed, is likely to be an important enabler for evolutionary adaptation. Environmental pressures may induce polymorphic behaviour, where different pressures result in different structural organisation. Here we show that by combining covalent and non-covalent bond formation three distinct polymorphs can emerge from the same small dynamic molecular network: vesicular aggregates, self-replicating fibres and nanoribbons, depending on the nature of the solvent environment. Additionally, a particular set of conditions allows the transient co-existence of both vesicles and fibres

Self‐Sorting in Dynamic Combinatorial Libraries Leads to the Co‐Existence of Foldamers and Self‐Replicators

Nature segregates fundamental tasks such as information storage/transmission and catalysis between two different compound classes (e.g. polynucleotides for replication and folded polyamides for catalysis). This division of labor is likely a product of evolution, raising the question of how simpler systems in which replicators and folded macromolecules co-exist may emerge in the transition from chemistry to biology. In synthetic systems, achieving co-existence of replicators and foldamers in a single molecular network remains an unsolved problem. Previous work on dynamic molecular networks has given rise to either self-replicating fibers or well-defined foldamer structures (or completely un-sorted complex systems). We report a system in which two cross-reactive dithiol (nucleobase- and peptide-based) building blocks self-sort into a replicator fiber and foldamer that both emerge spontaneously and co-exist. The self-sorting behavior remains prevalent across different building block ratios as two phases of emergence occur: replicator growth followed by foldamer formation. This is attributed to the autocatalytic formation of the replicator fiber, followed by enrichment of the system in the remaining building block, which is subsequently incorporated into a foldamer

A clip-like host that undergoes self-assembly and competitive guest-induced disassembly in water

<p>Certain calix[4]arenes that are anionic and appended with a single hydrophobic substituent can self-assemble into homodimers in water. The unusual behaviours of these assemblies in water solutions are largely attributed to them being formed from like-charged building blocks. We report here a new entry into this series – a difunctionalized analog with two hydrophobic arms, a net – 3 charge on each monomer, and an overall U-shaped ‘clip’ topology. We use ¹H NMR, 1-D DOSY and ITC to show that the new compound dimerizes in water but remains monomeric in organic solvents. Various cationic ammonium ion guests are able to drive dimer disassembly in favor of 1:1 host-guest complexes. The extent of competition is proportional to overall guest hydrophobicity.</p

Analyte-Driven Disassembly and Turn-On Fluorescent Sensing in Competitive Biological Media

Many indicator displacement assays can detect biological analytes in water, but these often have reduced performance in the presence of an unavoidable component: NaCl. We report here a new self-assembled sensor, DimerDye, that uses a novel photochemical guest-sensing mechanism and that is intrinsically tolerant of cosolutes. We synthetically integrated a dye into a calixarene macrocycle, forming two new merocyanine calixarenes (<b>MCx-1</b> and <b>MCx-2</b>). Both compounds self-assemble into nonemissive dimers in water. The addition of good guests like trimethyllysine induces a turn-on fluorescence response of <b>MCx-1</b> due to simultaneous dimer dissociation and formation of an emissive host–guest complex. DimerDyes remain functional in solutions containing the various salts, metal ions, and cofactors that are needed for enzymatic reactions. <b>MCx-1</b> provides a real-time, turn-on fluorescence signal in response to the lysine methyltransferase reaction of PRDM9