title: Detection of a transient intramolecular hydrogen bond using (1)JNH scalar couplings.
abstract: Hydrogen bonds are essential for the structure, stability and folding of proteins. The identification of intramolecular hydrogen bonds, however, is challenging, in particular in transiently folded states. Here we studied the presence of intramolecular hydrogen bonds in the folding nucleus of the coiled-coil structure of the GCN4 leucine zipper. Using one-bond (1)JNH spin-spin coupling constants and hydrogen/deuterium exchange, we demonstrate that a transient intramolecular hydrogen bond is present in the partially helical folding nucleus of GCN(16-31). The data demonstrate that (1)JNH couplings are a sensitive tool for the detection of transient intramolecular hydrogen bonds in challenging systems where the effective/useable protein concentration is low. This includes peptides at natural abundance but also uniformly labeled biomolecules that are limited to low concentrations because of precipitation or aggregation.
authors.affiliation: Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
authors.forename: ShengQi
authors.initials: S
authors.lastname: Xiang
authors.affiliation: Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany; German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany; Centre for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany. Electronic address: Markus.Zweckstetter@dzne.de.
authors.forename: Markus
authors.initials: M
authors.lastname: Zweckstetter
mesh_terms: D000465:Algorithms; D000595:Amino Acid Sequence; D001665:Binding Sites; D006859:Hydrogen / Q000737:chemistry*; D006860:Hydrogen Bonding; D008969:Molecular Sequence Data; D011485:Protein Binding; D011506:Proteins / Q000737:chemistry*; D066244:Proton Magnetic Resonance Spectroscopy / Q000379:methods*
chemical_list: D011506:Proteins; D006859:Hydrogen
keywords: Folding; Hydrogen bond; NMR spectroscopy; Scalar coupling