trate (GNO, Alfa Aesar, Ward Hill, MA) for 6 h at 16 C. The products were collected and washed by centrifugation before analysis. For reactions at low concentration, native and denatured filaments at 0.2 mg mL ±1 were incubated in 1.6 mL polyethylene centrifuge tubes with 1 mL of a 0.1 M aqueous solution of gallium nitrate for 24 h at 25 C. The products were collected and washed by centrifugation before analysis. Base-catalyzed synthesis of Ga 2 O 3 was accomplished by dissolving 1.82 g (0.005 mol) of GNO in 30 g of water contained in a glass vessel, followed by the addition of 7.24 g (0.06 mol) of concentrated (~29 wt.-%) ammonium hydroxide (NH 4 OH). Precipitated product was collected and washed by centrifugation before heat treatment. Hydrated GNO was prepared by dissolving 1.82 g (0.005 mol) of GNO in 50 g of water contained in a glass vessel. The solution was mixed for 1 h, followed by room-temperature vacuum evaporation of the water. The dried powder product was used for further heat treatments. As-received GNO powder was used directly from the container for pyrolysis experiments. Thermal treatments of base-hydrolyzed, hydrated, and as-received GNO powders were conducted by heating 50 mg of starting material in alumina crucibles placed in quartz Schlenk tubes. Heat treatments (10 C min ±1 ) were carried out in air to temperatures between 200±1000 C for 1 h.X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM): Approximately 25 mg of each heat-treated sample was ground (with a silicon-powder internal standard) to a fine powder, placed on a glass microscope slide or a single-crystal (100) silicon wafer, and characterized by X-ray diffraction (Phillips X'Pert; Amsterdam, The Netherlands) using a gonio scan (20±60, 0.02 step ±1 , 5 s step ±1 ; source slit sizes of 1/4 and 1/2, and detector slit sizes of 1/4 and 0.2 mm). Surface features of Ga 2 O 3 powders and Ga 2 O 3 -coated silicatein filaments were imaged by a cold cathode field-emission scanning electron microscope (SEM; JEOL JSM 6300F, Peabody, MA) equipped with an energy dispersive spectrometer. Specimens were mounted on conductive carbon adhesive tabs (Ted Pella, Inc., Redding, CA) and imaged (at 5 kV or 10 kV) either uncoated (for energy dispersive spectroscopy analysis) or after gold/palladium sputter coating. Energy dispersive spectroscopy (EDS, Oxford Instruments, Palo Alto, CA) was performed in conjunction with SEM to qualitatively determine chemical composition of specimens. Ga 2 O 3 -coated filaments were imaged with a transmission electron microscope (TEM, JEOL 2000FX) to observe the coating morphologies and obtain structural information via electron diffraction patterns. Lattice fringes were imaged with a high-resolution TEM (HRTEM, JEOL 2010). Both TEMs were operated at 200 kV. TEM specimens were prepared by pipetting a small amount (~20 lL) of filament suspension (in water) onto holey-carbon copper grids (Ted Pella, Inc., Redding, CA). The grids were then dried at 40 C for 5 min. Samples were ...

Polymersomes are stable self-assembled architectures which mimic cell membranes. For characterization, membrane proteins can be incorporated into such bio-mimetic membranes by reconstitution methods, leading to so-called proteopolymersomes. In this work, we demonstrate the direct incorporation of a membrane protein into polymersome membranes by a cell-free expression system. Firstly, we demonstrate pore formation in the preformed polymersome membrane using α-hemolysin. Secondly, we use claudin-2, a protein involved in cell-cell interactions, to demonstrate the in vitro expression of a membrane protein into these polymersomes. Surface plasmon resonance (Biacore) binding studies with the claudin-2 proteopolymersomes and claudin-2 specific antibodies are performed to show the presence of the in vitro expressed protein in polymersome membranes.

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