Regensburg 2004 – wissenschaftliches Programm
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AKB: Biologische Physik
AKB 50: Poster Session "Biological Physics"
AKB 50.87: Poster
Freitag, 12. März 2004, 10:30–13:00, B
SARS membrane protein E in model membranes: structural — •Ziad Khattari1, Guillaume Brotons1, Tim Salditt1, and Shy Arkin2 — 1Institut fuer Roentgenphysik, Universitaet Goettingen, Goettingen — 2Department of Biological Chemistry, Hebrew University, Jerusalm
We present a structural investigation of the SARS membrane protein E in model membranes by x-ray reflectivity. After the recent publication of the SARS coronavirus genome [1], structural characterization of its membrane active proteins is of great importance. The SARS membrane protein E is believed to be a viral ion channel, but it may also exhibit fusiogenic functions. The structure and interaction of the membrane active part of the protein is therefore investigated in model membranes. Using x-ray reflectivity on highly aligned stacks of membranes on silicon surfaces in the fluid La phase [2,3], we can determine the electron density profile of the lipid bilayer as a function of peptide-lipid (P/L) ratio. Structural properties of the peptide can be determined, as well as changes in lipid bilayer properties as a function of protein concentration may be assessed, ranging from bilayer thickness to acyl chain ordering and head-group hydration. In addition we use site-specific iodination as a marker in the density profile. Measurements have been performed at the D4 bending magnet station of HASYLAB/DESY. The results are complemented by spatial restraints from FTIR spectroscopy on samples containing site-specific isotopic labels (peptidic 13C=18O). [1] Marra et al. Science 300, 1399 (2003). [2] T. Salditt et al, Eur. Phys. J. E 7, 105 (2002). [3] Li, C. et al, accepted in J. Phys. D.