Membranes are the key structures to separate and spatially organize cellular systems. Their rich dynamics and transformations during the cell cycle are orchestrated by specific membrane‐targeted ...molecular machineries, many of which operate through energy dissipation. Likewise, man‐made light‐activated molecular rotary motors have previously shown drastic effects on cellular systems, but their physical roles on and within lipid membranes remain largely unexplored. Here, the impact of rotary motors on well‐defined biological membranes is systematically investigated. Notably, dramatic mechanical transformations are observed in these systems upon motor irradiation, indicative of motor‐induced membrane expansion. The influence of several factors on this phenomenon is systematically explored, such as motor concentration and membrane composition., Membrane fluidity is found to play a crucial role in motor‐induced deformations, while only minor contributions from local heating and singlet oxygen generation are observed. Most remarkably, the membrane area expansion under the influence of the motors continues as long as irradiation is maintained, and the system stays out‐of‐equilibrium. Overall, this research contributes to a comprehensive understanding of molecular motors interacting with biological membranes, elucidating the multifaceted factors that govern membrane responses and shape transitions in the presence of these remarkable molecular machines, thereby supporting their future applications in chemical biology.
Explore the nuanced relationship between light‐driven molecular motors and lipid membranes in this research. Delve into the continuous interplay, observing how these motors, akin to dynamic springs fueled by light, orchestrate subtle yet fascinating shape transitions in membranes. Observe how these out‐of‐equilibrium systems can modulate area expansion through their action in lipid membranes.
Nanofabrication has experienced a big boost with the invention of DNA origami, enabling the production and assembly of complex nanoscale structures that may be able to unlock fully new ...functionalities in biology and beyond. The remarkable precision with which these structures can be designed and produced is, however, not yet matched by their assembly dynamics, which can be extremely slow, particularly when attached to biological templates, such as membranes. Here, the rapid and controlled formation of DNA origami lattices on the scale of hundreds of micrometers in as little as 30 minutes is demonstrated, utilizing active patterning by the E.coli Min protein system, thereby yielding a remarkable improvement over conventional passive diffusion‐based assembly methods. Various patterns, including spots, inverse spots, mazes, and meshes can be produced at different scales, tailored through the shape and density of the assembled structures. The differential positioning accomplished by Min‐induced diffusiophoresis even allows the introduction of “pseudo‐colors”, i.e., complex core–shell patterns, by simultaneously patterning different DNA origami species. Beyond the targeted functionalization of biological surfaces, this approach may also be promising for applications in plasmonics, catalysis, and molecular sensing.
DNA origami revolutionized nanofabrication, allowing precise assembly of nanostructures. Despite this, large‐scale assembly remains challenging. The authors present a breakthrough: the rapid and controlled formation of DNA origami lattices using the Min protein system. Achieving large‐scale lattices in just 30 minutes, this method outperforms conventional diffusion‐based approaches. Multiple patterns and core‐shell architectures open up possibilities for advanced functionalization with various applications.
Self‐assembly of biological molecules and structures is a fundamental property of life. Whereas most biological functions are based on self‐assembled proteins and protein complexes, the self‐assembly ...of lipids is important for the spatial organization of heterogeneous cellular reaction environments and to catalyze cooperative interactions on/with membranes. Lipid domains or “rafts”, which are known to selectively recruit proteins, play an important functional role in sorting and trafficking of membrane components between subcellular organelles. However, how the recruitment and interactions of proteins in turn contributes to the formation and turnover of these structures has not been systematically addressed, due to the large variety in membrane–protein features and their spatiotemporal dynamics. The small size and transient nature of lipid domains adds to the complexity in visualizing them in living cells. Here, DNA origami is presented as a programmable tool to mimic protein clustering and assembly on membranes and illustrate how nanometer sized lipid domains coalesce into visible domains upon origami self‐assembly in defined patterns. Hence, the local membrane composition can be efficiently regulated by the self‐assembly of peripheral membrane binders. This reinforces the hypothesis that lipid rafts in cells occur as a result of membrane–protein interactions and, in particular, protein self‐assembly.
Self‐assembly of both lipids and anchored DNA origami is codependent on each other. Lipid domains coalesce with the cross‐linking of DNA origami following their preference for lipid domains at specific salt conditions. As a result, lipid domains can be patterned by bound DNA origami on the membrane.
Nanotechnology often exploits DNA origami nanostructures assembled into even larger superstructures up to micrometer sizes with nanometer shape precision. However, large-scale assembly of such ...structures is very time-consuming. Here, we investigated the efficiency of superstructure assembly on surfaces using indirect cross-linking through low-complexity connector strands binding staple strand extensions, instead of connector strands binding to scaffold loops. Using single-molecule imaging techniques, including fluorescence microscopy and atomic force microscopy, we show that low sequence complexity connector strands allow formation of DNA origami superstructures on lipid membranes, with an order-of-magnitude enhancement in the assembly speed of superstructures. A number of effects, including suppression of DNA hairpin formation, high local effective binding site concentration, and multivalency are proposed to contribute to the acceleration. Thus, the use of low-complexity sequences for DNA origami higher-order assembly offers a very simple but efficient way of improving throughput in DNA origami design.
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In article number 2300173, Petra Schwille and co‐workers demonstrate the capabilities of Min proteins to arrange cargo molecules into distinct patterns on the surface of artificially ...developed 3D systems. This work explores the versatility of the MinDE protein system and shows how this synthetic patterning tool excels at functionalizing microcarrier systems like lipid vesicles and 3D‐printed microswimmers relevant for synthetic biology and microrobotics.
The bottom‐up reconstitution of proteins for their modular engineering into synthetic cellular systems can reveal hidden protein functions in vitro. This is particularly evident for the bacterial Min ...proteins, a paradigm for self‐organizing reaction‐diffusion systems that displays an unexpected functionality of potential interest for bioengineering: the directional active transport of any diffusible cargo molecule on membranes. Here, the MinDE protein system is reported as a versatile surface patterning tool for the rational design of synthetically assembled 3D systems. Employing two‐photon lithography, microswimmer‐like structures coated with tailored lipid bilayers are fabricated and demonstrate that Min proteins can uniformly pattern bioactive molecules on their surface. Moreover, it is shown that the MinDE system can form stationary patterns inside lipid vesicles, which allow the targeting and distinctive clustering of higher‐order protein structures on their inner leaflet. Given their facile use and robust function, Min proteins thus constitute a valuable molecular toolkit for spatially patterned functionalization of artificial biosystems like cell mimics and microcarriers.
In this report, the authors test the capabilities of the MinDE protein system to organize molecules of different natures and complexities into distinct patterns. Techniques spanning from two‐photon direct laser writing, lipid membrane coating of surfaces, and protein encapsulation in lipid vesicles are employed to demonstrate that this protein‐based tool can pattern the surface of artificially‐designed 3D architectures.
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