A pulsed field gradient NMR diffusion investigation of enkephalin peptide-sodium dodecyl sulfate micelle association

2006 John Wiley & Sons, Ltd.

Détails bibliographiques
Publié dans:Magnetic resonance in chemistry : MRC. - 1985. - 44(2006), 6 vom: 19. Juni, Seite 586-93
Auteur principal: Begotka, Brandon A (Auteur)
Autres auteurs: Hunsader, Jennifer L, Oparaeche, Chinelo, Vincent, Jonathan K, Morris, Kevin F
Format: Article
Langue:English
Publié: 2006
Accès à la collection:Magnetic resonance in chemistry : MRC
Sujets:Journal Article Research Support, Non-U.S. Gov't Amino Acids Micelles Sodium Dodecyl Sulfate 368GB5141J Enkephalin, Methionine 58569-55-4 Enkephalin, Leucine 58822-25-6
Description
Résumé:2006 John Wiley & Sons, Ltd.
Pulsed field gradient NMR (PFG-NMR) diffusion experiments were used to investigate the binding of leucine and methionine enkephalin peptides to anionic sodium dodecyl sulfate (SDS) micelles. The study was undertaken to investigate the mechanism of interaction between enkephalin peptides and SDS micelles and to determine if NMR-derived association constants, K(eq), can predict the elution order in electrokinetic chromatography (EKC). In EKC, peptides are separated on the basis of their interactions with micelles. The Leu-enkephalin peptide-micelle association constant increased from 130 +/- 8 to 1459 +/- 57 and 1744 +/- 64 M(-1), respectively, when an Arg or Lys was added to the C-terminus. The association constant of Leu-enkephalinamide was approximately equal to that of Leu-enkephalin-Arg. Substitution of Phe4 with a Trp or Gly2 with an Ala in the Leu-enkephalin peptides also increased the micelle binding affinity. These results confirm that the interaction of Leu-enkephalin peptides with SDS micelles is largely electrostatic and that the non-polar amino acid side chains interact with the hydrophobic micelle core. The peptide-micelle association constants for the cationic Met-enkephalin peptides were also greater than their zwitterionic counterparts. For example, the Met-enkephalin K(eq) value was 162 +/- 9 M(-1), while the association constants for Met-enkephalin-Arg, Met-enkephalin-Lys, and Met-enkephalinamide were, respectively, 674 +/- 31, 426 +/- 23, and 453 +/- 27 M(-1). In both Met-enkephalin and Met-enkephalinamide, replacing Gly2 with an Ala did not significantly increase the association constant. These results confirm that with the Met-enkephalin peptides, there was little or no interaction of the amino acid side chains with the micelle core. For both the Leu-enkephalin and Met-enkephalin peptides, the association constants were consistent with EKC results, in that the peptides with smaller K(eq) values were found to elute before those with larger association constants
Description:Date Completed 05.09.2007
Date Revised 21.11.2013
published: Print
Citation Status MEDLINE
ISSN:1097-458X