A complex cellular process was reconstructed using a multiprotein polymersome system. ATP has been produced by coupled reactions between bacteriorhodopsin, a light-driven transmembrane proton pump, and F(0)F(1)-ATP synthase motor protein, reconstituted in polymersomes. This indicates that ATP synthase maintained its ATP synthesis and therefore its motor activity in the artificial membranes. This hybrid proteopolymersome will have wide application in a number of fields ranging from the in vitro investigation of cellular metabolism to the synthesis of functional "smart" materials.

Biomolecular motors such as F1-adenosine triphosphate synthase (F1-ATPase) and myosin are similar in size, and they generate forces compatible with currently producible nanoengineered structures. We have engineered individual biomolecular motors and nanoscale inorganic systems, and we describe their integration in a hybrid nanomechanical device powered by a biomolecular motor. The device consisted of three components: an engineered substrate, an F1-ATPase biomolecular motor, and fabricated nanopropellers. Rotation of the nanopropeller was initiated with 2 mM adenosine triphosphate and inhibited by sodium azide.

Biological pores have been used to study the transport of DNA and other molecules but most pores have channels that allow only the movement of small molecules and single-stranded DNA and RNA. The bacteriophage phi29 DNA-packaging motor, which allows double-stranded DNA to enter and exit during a viral infection, contains a connector protein that has a 3.6 – 6.0 nm wide channel. Here we show that a modified version of the connector protein, when reconstituted into liposomes and inserted into planar lipid bilayers, can act as conductive channels to allow the translocation of double-stranded DNA. Single-channel conductance assays and quantitative PCR confirmed the translocation through the pore. The measured conductance of a single connector channel was 4.8 nS in 1 M KCl. This engineered and membrane-adapted phage connector is expected to have interesting applications in nanotechnology and nanomedicine, such as MEMS sensing, microreactors, gene delivery, drug loading, and DNA sequencing.

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Current procedures for manual extraction of mature muscle tissue in micromechanical structures are time consuming and can damage the living components. To overcome these limitations, we have devised a new system for assembling muscle-powered microdevices based on judicious manipulations of materials phases and interfaces. In this system, individual cells grow and self-assemble into muscle bundles that are integrated with micromechanical structures and can be controllably released to enable free movement. Having realized such an assembly with cardiomyocytes we demonstrate two potential applications: a force transducer able to characterize in situ the mechanical properties of muscle and a self-assembled hybrid (biotic/abiotic) microdevice that moves as a consequence of collective cooperative contraction of muscle bundles. Because the fabrication of silicon microdevices is independent of the subsequent assembly of muscle cells, this system is highly versatile and may lead to the integration of cells and tissues with a variety of other microstructures.