Designed Negative Feedback from Transiently Formed Catalytic Nanostructures

Abstract

Highly dynamic and complex systems of microtubules undergo a substrate‐induced change of conformation that leads to polymerization. Owing to the augmented catalytic potential at the polymerized state, rapid hydrolysis of the substrate is observed, leading to catastrophe, thus realizing the out‐of‐equilibrium state. A simple synthetic mimic of these dynamic natural systems is presented, where similar substrate induced conformational change is observed and a transient helical morphology is accessed. Further, augmented catalytic potential of these helical nanostructures leads to rapid hydrolysis of the substrate providing negative feedback on the stability of the nanostructures and realization of an out‐of‐equilibrium state. This simple system, made from amino acid functionalized lipids, demonstrates a substrate‐induced self‐assembled state, where the fuel‐to‐waste conversion leads to the temporal presence of helical nanostructures.

ATP-fuelled self-assembly to regulate chemical reactivity in the time domain

“…[11][12][13][14] Whereas the majority of these studies have been dedicated to the development of materials and a study of their properties, the exploitation of chemically-fuelled driven selfassembly for the purpose of controlling chemical reactivity has received much less attention. [15][16][17][18][19][20][21][22][23][24][25] Here, we exploit adenosine triphosphate (ATP)-fuelled self-assembly 16,[26][27][28][29] to control the reaction kinetics in a reaction mixture in which two reactions take place concurrently (Fig. 1).…”

Devising Synthetic Reaction Cycles for Dissipative Nonequilibrium Self‐Assembly

“…Thus the self‐assembled structures create a negative feedback mechanism, which causes their own disassembly. Das and co‐workers used the C18H molecule to coassemble with a similar amphiphile with C18 stearoyl and l ‐phenylalanine amino acid appended with nitrophenol (C18‐FNP) 53. The coassembly of C18H and C18‐FNP amphiphiles gives helical structures.…”

“…(2) where the same chemistry (catalyzed or not) is responsible for all activation and/or deactivation steps;48–50 Cat. (3) where a catalyst exclusively acts on one specific step of the reaction cycle 51–54…”

On the Use of Catalysis to Bias Reaction Pathways in out Of-Equilibrium Systems

“…Moreover, coupling catalysis to a dissipative CRN containing assembling products could give rise to unusual assembly behaviour and feedback. 26,27,28 Here, instead of using enzymes, with limited operational stability and high specificity, it would be recommended to start exploring small molecules and metal catalysts. This way organocatalysis in combination with metal catalysis in non-natural systems can play similar roles as enzymes in nature and provide new systems with a high degree of control and an adaptive character.…”