Secondary structure, dynamics, and architecture of the p7 membrane protein from hepatitis C virus by NMR spectroscopy.
P7 is a small membrane protein that is essential for the infectivity of hepatitis C virus. Solution-state NMR experiments on p7 in DHPC micelles, including hydrogen/deuterium exchange, paramagnetic relaxation enhancement and bicelle 'q-titration,' demonstrate that the protein has a range of dynamic properties and distinct structural segments. These data along with residual dipolar couplings yield a secondary structure model of p7. We were able to confirm previous proposals that the protein has two transmembrane segments with a short interhelical loop containing the two basic residues K33 and R35. The 63-amino acid protein has a remarkably complex structure made up of seven identifiable sections, four of which are helical segments with different tilt angles and dynamics. A solid-state NMR two-dimensional separated local field spectrum of p7 aligned in phospholipid bilayers provided the tilt angles of two of these segments. A preliminary structural model of p7 derived from these NMR data is presented.
Cook
Gabriel A
GA
Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA.
Opella
Stanley J
SJ
D041961:Deuterium Exchange Measurement; D017666:Deuterium Oxide / Q000737:chemistry; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D016174:Hepacivirus / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D010742:Phospholipid Ethers / Q000737:chemistry; D017433:Protein Structure, Secondary; D014764:Viral Proteins / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D000086082:Viroporin Proteins
D017666:Deuterium Oxide; D004134:Dimyristoylphosphatidylcholine; D010742:Phospholipid Ethers; D014764:Viral Proteins; D014867:Water; C052298:1,2-dihexadecyl-sn-glycero-3-phosphocholine; C088369:p7 protein, Hepatitis C virus; D000086082:Viroporin Proteins