Circular Dichroism is Sensitive to Monovalent Cation Binding in Monensin Complexes

Ahmed Nedzhib, Jiří Kessler, Petr Bouř, Béla Gyurcsik, Ivayla Pantcheva

Research output: Article

1 Citation (Scopus)

Abstract

Monensin is a natural antibiotic that exhibits high affinity to certain metal ions. In order to explore its potential in coordination chemistry, circular dichroism (CD) spectra of monensic acid A (MonH) and its derivatives containing monovalent cations (Li+, Na+, K+, Rb+, Ag+, and Et4N+) in methanolic solutions were measured and compared to computational models. Whereas the conventional CD spectroscopy allowed recording of the transitions down to 192 nm, synchrotron radiation circular dichroism (SRCD) revealed other bands in the 178–192 nm wavelength range. CD signs and intensities significantly varied in the studied compounds, in spite of their similar crystal structure. Computational modeling based on the Density Functional Theory (DFT) and continuum solvent model suggests that the solid state monensin structure is largely conserved in the solutions as well. Time-dependent Density Functional Theory (TDDFT) simulations did not allow band-to-band comparison with experimental spectra due to their limited precision, but indicated that the spectral changes were caused by a combination of minor conformational changes upon the monovalent cation binding and a direct involvement of the metal electrons in monensin electronic transitions. Both the experiment and simulations thus show that the CD spectra of monensin complexes are very sensitive to the captured ions and can be used for their discrimination. Chirality 28:420–428, 2016.

Original languageEnglish
Pages (from-to)420-428
Number of pages9
JournalChirality
Volume28
Issue number5
DOIs
Publication statusPublished - jan. 1 2016

ASJC Scopus subject areas

  • Analytical Chemistry
  • Catalysis
  • Pharmacology
  • Drug Discovery
  • Spectroscopy
  • Organic Chemistry

Fingerprint Dive into the research topics of 'Circular Dichroism is Sensitive to Monovalent Cation Binding in Monensin Complexes'. Together they form a unique fingerprint.

  • Cite this