Inside Cover: Active Mechanical Threading by a Molecular Motor (Angew. Chem. Int. Ed. 19/2022)

Abstract

A molecular motor setup that allows harnessing the trajectory of directional motor rotation for an active mechanical threading process is presented by Henry Dube and co‐workers in their Research Article (e202201882). The motor is embedded into a macrocycle and its indane‐based rotor fragment then serves as a “revolving door” in the light‐driven rotation. In this way a process akin to macroscopic threading of a needle is miniaturized to the molecular level, offering a first entry point to mechanical molecular knitting or weaving processes.

Synchronizing Two Distinct Nano‐Circular Sliding Motions in Six‐Component Machinery for Double Catalysis

“…While motional speed in artificial machines has been a topic of great interest, [4–9] lately even in combination with catalysis, [10–13] we decided to pursue the concept of synchronized movement [14, 15] in catalytic multicomponent machinery alike that in enzymes. Coupling of motion in individual self‐assembled machines with multiple moving parts is very rarely reported, [16–18] and even less regarding distinct catalytic behavior [19] .…”

“…Via efficient intercomponent communication, conformational changes in the F o subunit lead to cyclic structural changes in the F 1 unit which mediate a phase-shifted conversion of ADP and P i to ATP. [3] While motional speed in artificial machines has been a topic of great interest, [4][5][6][7][8][9] lately even in combination with catalysis, [10][11][12][13] we decided to pursue the concept of synchronized movement [14,15] in catalytic multicomponent machinery alike that in enzymes. Coupling of motion in individual selfassembled machines with multiple moving parts is very rarely reported, [16][17][18] and even less regarding distinct cata-lytic behavior.…”

“…An unmatched mechanism explaining the coupled motion and synchronization of speed via intercomponent communication, mimicking long-range communication in natural systems via the protein backbone-(s), [2] is provided. The mechanism conceptually has nothing at all in common with intimate steric interactions [14,28] or interdigitated geared motion [18,20,21] as in other man-made devices. Further, we have demonstrated how the coupling of both motions liberated two catalysts in high effective concentrations, a feature that was used to increase the yields in the double catalysis of benzofuran and indole products.…”

The Influence of Strain on the Rotation of an Artificial Molecular Motor

“…[8] One possible way to achieve this target is by constraining the motion of the motor, i.e. applying a mechanical load, so that parts of the motor movement are converted into, for instance, coupled motion [33][34][35][36][37]51] or chemical strain [17,31,[52][53][54][55][56][57][58][59] of a secondary molecular entity. Detailed mechanistic studies of photochemical molecular motors that perform work against a mechanical load, applied by connecting their contra-rotating halves with molecular tethers, were reported by the Dube, [34,36] Giuseppone [59] and our group.…”

The Influence of Strain on the Rotation of an Artificial Molecular Motor

“…transducing the energy that is put into the system into other forms of energy, by avoiding heat dissipation as efficiently as possible. [5,8,10,11] In recent years, molecular machinists developed AMMs that can execute more and more sophisticated tasks, such as multifunctional catalysis, [12][13][14] contracting or moving macroscopic objects, [15][16][17][18][19][20][21][22] penetrating and affecting cell walls, [23][24][25] transporting and assembling molecular entities, [26][27][28][29] shifting chemical equilibria, [30,31] performing coupled motions [32][33][34][35][36][37] or pumping molecular entities. [38][39][40][41][42][43] As demonstrated in the examples above, photochemical molecular motors [44][45][46][47][48][49][50] can be crucial components in AMMs.…”