1dip
THE SOLUTION STRUCTURE OF PORCINE DELTA-SLEEP-INDUCING PEPTIDE IMMUNOREACTIVE PEPTIDE, NMR, 10 STRUCTURES
|
OverviewOverview
The 77-residue delta sleep-inducing peptide immunoreactive peptide (DIP), is a close homolog of the Drosophila melanogaster shortsighted gene, product. Porcine DIP (pDIP) and a peptide containing a leucine, zipper-related partial sequence of pDIP, pDIP(9-46), was synthesized and, studied by circular dichroism and nuclear magnetic resonance spectroscopy, in combination with molecular dynamics calculations. Ultracentrifugation, size exclusion chromatography, and model calculations indicated that pDIP, forms a dimer. This was confirmed by the observation of, concentration-dependent thermal folding-unfolding transitions. From CD, spectroscopy and thermal folding-unfolding transitions of pDIP(9-46), it, was concluded that the dimerization of pDIP is a result of interaction, between helical structures localized in the leucine zipper motif. The, three-dimensional structure of the protein was determined with a modified, simulated annealing protocol using experimental data derived from nuclear, magnetic resonance spectra and a modeling approach based on an established, strategy for coiled coil structures. The left-handed super helical, structure of the leucine zipper type sequence resulting from the modeling, approach is in agreement with known leucine zipper structures. In addition, to the hydrophobic interactions between the amino acids at the heptade, positions a and d, the structure of pDIP is stabilized by the formation of, interhelical i to i' + 5 salt bridges. This result was confirmed by the pH, dependence of the thermal-folding transitions. In addition to the, amphipatic helix of the leucine zipper, a second helix is formed in the, NH2-terminal part of pDIP. This helix exhibits more 310-helix character, and is less stable than the leucine zipper helix. For the COOH-terminal, region of pDIP no elements of regular secondary structure were observed.
About this StructureAbout this Structure
1DIP is a Single protein structure of sequence from Sus scrofa with ACE as ligand. Full crystallographic information is available from OCA.
ReferenceReference
Solution structure of porcine delta sleep-inducing peptide immunoreactive peptide A homolog of the shortsighted gene product., Seidel G, Adermann K, Schindler T, Ejchart A, Jaenicke R, Forssmann WG, Rosch P, J Biol Chem. 1997 Dec 5;272(49):30918-27. PMID:9388238
Page seeded by OCA on Tue Nov 20 13:18:26 2007