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Biphenyl-capped phosphopeptides instruct cell aggregation into spheroids, with minimal effective concentrations below 10 μM. Key factors driving morphogenesis include the self-assembly ability and dynamic shapeshifting of the peptide assemblies. 

Abstract Rapid cellular uptake of synthetic molecules remains a challenge, and the motif frequently employed to generate prodrugs, succinic ester, unfortunately lowers the efficacy of the desired drugs due to their slow ester hydrolysis and low cell entry. Here we show that succinic ester‐containing diglycine drastically boosts the cellular uptake of supramolecular assemblies or prodrugs. Specifically, autohydrolysis of the diglycine‐activated succinic esters turns the nanofibers of the conjugates of succinic ester and self‐assembling motif into nanoparticles for fast cellular uptake. The autohydrolysis of diglycine‐activated succinic esters and drug conjugates also restores the efficacy of the drugs. 2D nuclear magnetic resonance (NMR) suggests that a “U‐turn” of diglycine favors intramolecular hydrolysis of diglycine‐activated succinic esters to promote autohydrolysis. As an example of rapid autohydrolysis of diglycine‐activated succinic esters for instant cellular uptake, this work illustrates a nonenzymatic bond cleavage approach to develop effective therapeutics for intracellular targeting. 

Abstract The intricate nature of eukaryotic cells with intracellular compartments having differences in component concentration and viscosity in their lumen provides (membrane‐active) enzymes to trigger time‐ and concentration‐dependent processes in the intra‐/extracellular matrix. Herein, membrane‐active, enzyme‐loaded artificial organelles (AOs) are capitalized upon to develop fluidic and stable proteinaceous membrane‐based protocells. AOs in protocells induce the self‐assembly of oligopeptides into an artificial cytoskeleton that underlines their influence on the structure and functionality of protocells. A series of microscopical tools is used to validate the intracellular assembly and distribution of cytoskeleton, the changing protocells morphology, and AOs inclusion within cytoskeletal growth. Thus, the dynamics, diffusion, and viscosity of intracellular components in the presence of cytoskeleton are evaluated by fluorescence tools and enzymatic assay. Membrane‐active alkaline phosphatase in polymersomes as AOs fulfills the requirements of biomimetic eukaryotic cells to trigger intracellular environment, mobility, viscosity, diffusion, and enzymatic activity itself as well as high mechanical stability and high membrane fluidity of protocells. Thus membrane‐active AOs in protocells provide a variable reaction space in a changing intracellular environment and underline their regulatory role in the fabrication of complex protocell architectures and functions. This study contributes significantly to the effective biomimetics of cell‐like structures, shapes, and functions. 

Abstract While bond formation has historically been the mainstay of medicinal chemistry, the phenomenon of bond cleavage has received less focus. However, the success of numerous oral medications demonstrates the importance of controlled cleavage in prodrugs to achieve desired therapeutic outcomes. Nevertheless, effective strategies to control this cleavage remain limited. This concept article introduces a novel approach: employing peptides as conjugates to drugs to modulate the hydrolysis of these conjugates and enhance drug efficacy. The article begins by briefly outlining common prodrug strategies, followed by a few representative examples of how peptides can be leveraged to control the autohydrolysis of peptide‐conjugated prodrugs for bacterial and cancer cell inhibition. Finally, it provides a brief outlook on the future potential of this promising new research direction in molecular medicine. 

Enzymatic noncovalent synthesis enables the spatiotemporal control of multimolecular crowding in cells, thus offering a unique opportunity for modulating cellular functions. This article introduces some representative enzymes and molecular building blocks for generating peptide assemblies as multimolecular crowding in cells, highlights the relevant biomedical applications, such as anticancer therapy, molecular imaging, trafficking proteins, genetic engineering, artificial intracellular filaments, cell morphogenesis, and antibacterial, and briefly discusses the promises of ENS as a multistep molecular process in biology and medicine. 

In ferroelectric heterostructures, the interaction between intrinsic polarization and the electric field generates a rich set of localized electrical properties. The local electric field is determined by several connected factors, including the charge distribution of individual unit cells, the interfacial electromechanical boundary conditions, and chemical composition of the interfaces. However, especially in ferroelectric perovskites, a complete description of the local electric field across micro-, nano-, and atomic-length scales is missing. Here, by applying four-dimensional scanning transmission electron microscopy (4D STEM) with multiple probe sizes matching the size of structural features, we directly image the electric field of polarization vortices in (PbTiO3)16/(SrTiO3)16 superlattices and reveal different electric field configurations corresponding to the atomic scale electronic ordering and the nanoscale boundary conditions. The separability of two different fields probed by 4D STEM offers the possibility to reveal how each contributes to the electronic properties of the film.