Premium
NMR evidence of a valinomycin–proton complex
Author(s) -
Kříž Jaroslav,
Makrlík Emanuel,
Vaňura Petr
Publication year - 2005
Publication title -
biopolymers
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.556
H-Index - 125
eISSN - 1097-0282
pISSN - 0006-3525
DOI - 10.1002/bip.20384
Subject(s) - valinomycin , chemistry , proton , proton nmr , nmr spectra database , proton transport , spectral line , inorganic chemistry , ion , membrane , stereochemistry , organic chemistry , physics , quantum mechanics , astronomy , biochemistry
In addition to the well‐known complexes of valinomycin with alkali metal cations, an equimolar complex of the same compound with proton was found to be formed in nitrobenzene. Hydrogen bis(1,2‐dicarbollylide) cobaltate (HDCC) was used as a proton source. According to NMR spectra, the complex formation is quantitative at proton/valinomycin molar ratios up to 1:1 but there is fast exchange of protons between coordinated and uncoordinated valinomycin molecules at lower ratios. 1 H and 13 C NMR spectra show a dramatic change in the valinomycin conformation during its coordination with protons, probably from a propeller‐like to a bracelet‐like form. As valinomycin is one of the well‐known ion‐carrying ionophores facilitating especially the K + ion transport across a biological membrane, the existence of the valinomycin‐proton complex could be important in biochemistry and biology. © 2005 Wiley Periodicals, Inc. Biopolymers 81: 104–109, 2006 This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com