부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.bpj.2009.04.057 Byline: Elisa J. Cabre (a ), Jenny Malmstrom (a ), Duncan Sutherland (a ), J. Perez-Gil (a ), Daniel E. Otzen (a ) Abstract: Pulmonary surfactant protein B (SP-B) facilitates the rapid transfer of phospholipids from bilayer stores into air-liquid interfacial films along the breathing cycle, and contributes to the formation of a surface-associated multilayer reservoir of surfactant to optimize the stability of the respiratory interface. To obtain more insights into the mechanisms underlying this transfer and multilayer formation, we established a simple model system that captures different features of SP-B action. We monitored the formation of supported planar bilayers from the collapse of intact phospholipid vesicles on a silica surface using a technique called quartz crystal microbalance with dissipation, which provides information on changes in membrane thickness and viscosity. At physiologically relevant concentrations, SP-B dramatically alters vesicle collapse. This manifests itself as a reduced buildup of intact vesicles on the surface before collapse, and allows the stepwise buildup of multilayered deposits. Accumulation of lipids in these multilayer deposits requires the presence of SP-B in both the receptor and the arriving membranes, surrounded by a comparable phospholipid charge. Thus, the quartz crystal microbalance with dissipation system provides a useful, simplified way to mimic the effect of surfactant protein on vesicle dynamics and permits a detailed characterization of the parameters governing reorganization of surfactant layers. Author Affiliation: (a ) Departamento Bioquimica y Biologia Molecular I, Facultad de Biologia, Universidad Complutense, Madrid, Spain (a ) Interdisciplinary Nanoscience Research Center and Department of Molecular Biology, University of Aarhus, Aarhus, Denmark Article History: Received 28 February 2009; Accepted 29 April 2009 Article Note: (miscellaneous) Editor: William C. Wimley.