The structure of salt bridges between Arg+ and Glu− in peptides investigated with 2D-IR spectroscopy: Evidence for two distinct hydrogen-bond geometries

Abstract

The structure of salt bridges between Arg+ and Glu-in peptides investigated with 2D-IR spectroscopy: Evidence for two distinct hydrogen-bond geometries Huerta Viga, A.; Amirjalayer, S.; Rosa Domingos, S.M.; Meuzelaar, H.; Rupenyan, A.B.; Woutersen, S. Published in:Journal of Chemical Physics DOI:10.1063/1.4921064 Link to publication Citation for published version (APA):Huerta-Viga, A., Amirjalayer, S., Domingos, S. R., Meuzelaar, H., Rupenyan, A., & Woutersen, S. (2015). The structure of salt bridges between Arg+ and Glu-in peptides investigated with 2D-IR spectroscopy: Evidence for two distinct hydrogen-bond geometries. Journal of Chemical Physics, 142(21). DOI: 10.1063/1.4921064 General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Download date: 12 May 2018THE JOURNAL OF CHEMICAL PHYSICS 142, 212444 (2015) The structure of salt bridges between Arg Salt bridges play an important role in protein folding and in supramolecular chemistry, but they are difficult to detect and characterize in solution. Here, we investigate salt bridges between glutamate (Glu − ) and arginine (Arg + ) using two-dimensional infrared (2D-IR) spectroscopy. The 2D-IR spectrum of a salt-bridged dimer shows cross peaks between the vibrational modes of Glu − and Arg + , which provide a sensitive structural probe of Glu − · · · Arg + salt bridges. We use this probe to investigate a β-turn locked by a salt bridge, an α-helical peptide whose structure is stabilized by salt bridges, and a coiled coil that is stabilized by intra-and intermolecular salt bridges. We detect a bidentate salt bridge in the β-turn, a monodentate one in the α-helical peptide, and both salt-bridge geometries in the coiled coil. To our knowledge, this is the first time 2D-IR has been used to probe tertiary side chain interactions in peptides, and our results show that 2D-IR spectroscopy is a powerful method for investigating salt bridges in solution. C 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License. [http://dx

Guanidinium‐Induced Denaturation by Breaking of Salt Bridges

“…To compare the 2D-IR response of isolated Gdm + and Ac À ions with that of asolution containing Gdm + :Ac À dimers,we constructed 2D-IR spectra of a( hypothetical) mixture of monomeric Gdm + and Ac À by adding the individual experimental 2D-IR responses of NaAc and GdmDCl solution (Figure 3b,c). [39,41] The cross peaks,which indicate coupling between two vibrational modes,a re positive-negative doublets in the n probe direction. These cross peaks overlap with the more intense diagonal peaks,and can be seen more clearly in the polarization-difference spectrum (Figure 3f).…”

Identification of an α-MoRF in the Intrinsically Disordered Region of the Escargot Transcription Factor

“…Oppositely charged residues lead to the formation of salt bridges, 36 , 58 stabilizing local structures that can be relevant in molecular recognition events. 57 − 61 Salt bridges are known to impart local rigidity and the disruption of these interactions increases flexibility, 36 , 59 which could be associated with “order to disorder” structural transitions in IDPs. 36 We have found that the most persistent hydrogen bonds in the ensemble are those between E141, R144, and T145.…”

“… 36 We have found that the most persistent hydrogen bonds in the ensemble are those between E141, R144, and T145. Interactions between E and R contribute favorably to the stability of helices, 60 , 61 and interactions between E and R ( i + 3, i + 4) are more favorable than the reversed salt bridge. 61 Glutamate can establish side chain–backbone and side chain–side chain interactions, 62 while threonine has a short polar side chain and has a strong tendency to form hydrogen bonds with neighboring backbone amides, as seen in our simulations.…”

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