Molecular dynamics simulations of surfactant protein C mimic in phospholipid bilayers

COMP 93

Stephen M. Dutz, smdutz@csupomona.edu1, Zachary Ramjan, zhramjan@csupomona.edu1, Patrick W. Mobley, pwmobley@csupomona.edu1, Larry M. Gordon, lgordon2@san.rr.com2, Frans J. Walther, fwalther@labiomed.org2, Brian Vovan3, Jose M. Hernandez-Juviel, josemhj@labiomed.org2, Mark A. Sherman4, Alan J. Waring, awaring@mednet.ucla.edu5, and Shantanu Sharma, sks@csupomona.edu1. (1) Department of Chemistry and Center for Macromolecular Modeling & Materials Design (CM3D), California State Polytechnic University, 3801 West Temple Ave, Pomona, CA 91768, (2) L.A. Biomedical Research Institute, Harbor-UCLA Medical Center, Bldg. F5 South, 1124 West Carson Street, Torrance, CA 90502, (3) Department of Pediatrics, Harbor-UCLA Medical Center, 1124 West Carson Street, Bldg F-5 South, Torrance, CA 90502, (4) Department of Biomedical Informatics, Beckman Resarch Institute, City of Hope National Medical Center, Duarte, CA 91010, (5) Department of Medicine, UCLA School of Medicine, Center for the Health Sciences, CHS-37-055, 10833 Le Conte Avenue, Los Angeles, CA 90095
Surfactant protein C (SP-C) is an extremely hydrophobic lipopeptide found in mammalian lung surfactant. Important SP-C functions include lipid bilayer interactions with the lung surface monolayer and modulation of the surfactant lipid viscosity. Previous solution NMR studies in organic solvents indicate that the secondary structure of SP-C and the (34 residue) synthetic SP-C derivative SP-Cff is largely helical in this environment and is localized to the poly-valine sequence. Our infrared measurements of SP-Cff in palmitoyloleoylphosphatidylcholine (POPC) bilayers confirm the helical nature of the peptide, with the helical axis oriented parallel to the long axis of the phospholipid acyl chains. Moreover, our molecular dynamics simulations of SP-Cff in hydrated POPC bilayers validate the helical structure of the poly-valine sequence, with the helical axis oriented perpendicular to the bilayer surface.
 

Bold Predictions in Theoretical Chemistry: A Poster Session in Honor of One of the Boldest, Bill Goddard, on the Occasion of his 70th Birthday
7:30 PM-9:30 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Computers in Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007