1n6t
Solution Structure of the Tachykinin Peptide Neurokinin A
OverviewOverview
The solution structure of NKA, a decapeptide of mammalian origin, has been characterized by CD spectropolarimetry and 2D proton nuclear magnetic resonance (2D 1H-NMR) spectroscopy in both aqueous and membrane mimetic solvents. Unambiguous NMR assignments of protons have been made with the aid of correlation spectroscopy (DQF-COSY and TOCSY) experiments and nuclear Overhauser effect spectroscopy (NOESY and ROESY) experiments. The distance constraints obtained from the NMR data have been utilized to generate a family of structures, which have been refined using restrained energy minimization and dynamics. These data show that in water NKA prefers to be in an extended chain conformation whereas a helical conformation is induced in the central core and the C-terminal region (D4-M10) of the peptide in the presence of perdeuterated dodecylphosphocholine (DPC) micelles, a membrane model system. Though less defined the N-terminus also displays some degree of order and a possible turn structure. The conformation adopted by NKA in the presence of DPC micelles represents a structural motif typical of neurokinin-2 selective agonists and is similar to that reported for eledoisin in hydrophobic environment.
About this StructureAbout this Structure
1N6T is a Single protein structure. Full crystallographic information is available from OCA.
ReferenceReference
Three-dimensional structure of the mammalian tachykinin peptide neurokinin A bound to lipid micelles., Chandrashekar IR, Cowsik SM, Biophys J. 2003 Dec;85(6):4002-11. PMID:14645089 Page seeded by OCA on Sat May 3 02:10:03 2008