ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Chemistry  (3)
Collection
Keywords
Publisher
Years
  • 1
    Electronic Resource
    Electronic Resource
    Nmr studies of a series of dehydrodermorphins (1989)
    New York : Wiley-Blackwell
    Biopolymers 28 (1989), S. 129-138 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The third and fifth aromatic residues of dermorphin, a potent μ-opioid peptide, and of its N-terminal fragments, from the pentapeptide to the parent heptapeptide amide, have been systematically substituted with Z-dehydrophenylalanine (Δ-Phe) and/or Phe to investigate the conformation-activity relationship.The characterization in DMSO-d6 at 500 MHz indicates that, in this solvent, all peptides adopt essentially random, extended conformations, as a consequence of the strong solvation. The chemical shift of the methyl group of D-Ala is influenced by the precise orientation of the side chain of the third residue in a fashion that can be correlated to the μ potency, consistently with our model of μ-receptor.However, the complexes of the pentapeptides with 18-crown-6-ether, when dissolved in chloroform, adopt ordered, folded conformations, a behavior that closely parallels the CD observations in methanol.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360280115
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Conformational analysis of an opioid peptide in solvent media that mimic cytoplasm viscosity (1992)
    New York : Wiley-Blackwell
    Biopolymers 32 (1992), S. 367-372 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Many neuropeptides exert their action between the presynaptic vesicles and postsynaptic transmembrane receptors, crossing different layers of specialized cytoplasm. Biomimetic media usually employed to study bioactive peptides do not reproduce the physico chemical environment of cytoplasm - in particular, the high viscosity of this biological fluid. Here we describe a Conformational study of a δ-selective opioid peptide, deltorphin I, at variable temperatures in several biocompatible media characterized by varying values of viscosity and dielectric constant. It was found that only viscosity, among these parameters, induces ordered conformations; that is, it acts as a Conformational sieve. This finding suggests that the high viscosity of the intersynaptic fluid contributes, in addition to the membrane catalysis proposed by Schwyzer, in overcoming the so-called entropic barrier to the transition state of peptide-receptor interaction by selecting ordered conformations prior to receptor interaction.The folded conformer found in the 80 : 20 (v : v) DMSOd6/H2O cryoprotective mixture at 265 K has a shape consistent with those of rigid nonpeptidic opiates.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360320412
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Solution and solid state structure of an aib-containing cyclodecapeptide inhibiting the cholate uptake in hepatocytes (1996)
    New York : Wiley-Blackwell
    Biopolymers 40 (1996), S. 465-478 
    Details
    ISSN: 0006-3525
    Keywords: cyclic decapeptides ; cyclolinopeptide A ; x-ray ; nmr ; conformation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The conformational analysis of synthetic cyclodecapeptide c(Pro-Phe-Phe-Aib-Leu)2 related to the cyclolinopeptide A, in the solid state and solution, has been carried out by x-ray diffraction and nmr spectroscopy. The structure of the monoclinic form obtained from methanol [a = 11.351(5) Å, b = 27.455(2) Å, c = 12.716(8) Å, β = 99.65(3)°; space group P21; Z = 2] shows the presence of six intramolecular NH···CO hydrogen bonds, with formation of four turns (three of type I and one of type III) and two C16 ring structures. All peptide units are trans. The solution structure, as found by nmr, indicates that, at room temperature, the peptide is conformationally homogeneous; the structure determined is perfectly symmetrical and topologically similar to that found in the solid state. The cyclodecapeptide exhibits similar biological activity to cyclolinopeptide A. © 1997 John Wiley & Sons, Inc. Biopoly 40: 465-478, 1996
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...