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Langmuir 2008, 24, 3686-3689
Lipid Nanotube Formation from Streptavidin-Membrane Binding Haiqing Liu,† George D. Bachand,† Hahkjoon Kim,‡ Carl C. Hayden,‡ Elisa A. Abate,† and Darryl Y. Sasaki*,† Sandia National Laboratories, Biomolecular Interfaces and Systems Department, Albuquerque, New Mexico 87185, and Combustion Chemistry Department, Sandia National Laboratories, LiVermore, California 94551 ReceiVed December 23, 2007. In Final Form: February 16, 2008 A novel transformation of giant lipid vesicles to produce nanotubular structures was observed upon the binding of streptavidin to biotinylated membranes. Unlike membrane budding and tubulation processes caused by proteins involved with endocytosis and vesicle fusion, streptavidin is known to crystallize at near the isoelectric point (pI 5 to 6) into planar sheets against biotinylated films. We have found, however, that at neutral pH membranes of low bending rigidity (