|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department of Chemistry, Swarthmore College, Swarthmore, Pennsylvania 19081, USA
2 Department of Biochemistry and Cell Biology, Center for Structural Biology, and
3 Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794-5115, USA
4 Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
(RECEIVED September 10, 2004; FINAL REVISION November 30, 2004; ACCEPTED December 3, 2004)
A peptide designed to form a homo-oligomeric transmembrane helical bundle was reconstituted into lipid bilayers and studied by using 2H NMR (nuclear magnetic resonance) with magic angle spinning to confirm that the helical interface corresponds to the interface intended in the design. The peptide belongs to a family of model peptides derived from a membrane-solubilized version of the water-soluble coiled-coil GCN4-P1. The variant studied here contains two asparagines thought to engage in interhelical hydrogen bonding critical to the formation of a stable trimer. For the NMR studies, three different peptides were synthesized, each with one of three consecutive leucines in the transmembrane region deuterium labeled. Prior to NMR data collection, polarized infrared spectroscopy was used to establish that the peptides were reconstituted in lipid bilayers in a transmembrane helical conformation. The 2H NMR line shapes of the three different peptides are consistent with a trimer structure formed by the designed peptide that is stabilized by inter-helical hydrogen bonding of asparagines at positions 7 and 14.
Keywords: transmembrane peptides; helix association; 2H MAS NMR; ATR-FTIR
Article published online ahead of print. Article and publication date are at http://www.proteinscience.org/cgi/doi/10.1110/ps.041110605.
Reprint requests to: Kathleen P. Howard, Department of Chemistry, Swarthmore College, Swarthmore, PA 19081, USA; e-mail: khoward1{at}swarthmore.edu; fax: (610) 328-7355; or Steven O. Smith, Department of Biochemistry and Cell Biology, Center for Structural Biology, Stony Brook University, Stony Brook, NY 11794-5115; e-mail: steven.o.smith{at}sunysb.edu; fax: (631) 632-8575.
![]()
CiteULike
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |