NMR studies of exchanging amide protons in 1-desamino-8-D-argininevasopressin by selective Hartmann-Hahn transfer
✍ Scribed by Klaus Zangger; Heinz Sterk
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 337 KB
- Volume
- 33
- Category
- Article
- ISSN
- 0749-1581
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✦ Synopsis
Abstract
Proton exchange rates between the solvent H~2~O and the amidic protons of a nonapeptide (1‐desamino‐8‐D)‐argininevasopressin in aqueous solution were determined by using selective nuclear magnetic double‐resonance methods. Transverse magnetization, the magnitude of which depends on the chemical exchange rate and the relaxation time T~1~, is transferred via doubly selective homonuclear Hartmann‐Hahn mixing to a scalar coupling partner. With respect to well established two‐dimensional experiments, this one‐dimensional alternative has two advantages: it is much less time consuming and, as a true benefit, it is even applicable when two signals which are in exchange with the same compound (solvent) are overlapping. The evaluation of amide proton exchange rates in the investigated peptide led to the assumption of an intramolecular hydrogen bond.