Cation ion specifically induces a conformational change in trans-dehydroandrosterone - a solid-state NMR study
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Updated: Apr 18, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Darong Wang1, Meiman Chen1, Rong-Jie Chein1
1Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan, ROC.
Abstract:
In this work, we demonstrated that calcium (Ca(+2)) is able to induce a conformational change in trans-dehydroandrosterone (DHEA). To this respect, solid-state NMR spectroscopy was applied to a series of DHEA molecules that were incubated with Ca(+2) under different concentrations. The high-resolution (13)C NMR spectra of the DHEA/Ca(+2) mixtures exhibited two distinct sets of signals; one was attributed to DHEA in the free form, and the second set was due to the DHEA/Ca(+2) complex. Based on chemical shift isotropy and anisotropy analyses, we postulated that Ca(+2) might have associated with the oxygen attached to C17 via a lone-pair of electrons, which induced a conformational change in DHEA. Apart from Ca(+2), we also incubated DHEA with magnesium (Mg(+2)) to determine whether Mg(+2) was able to interact with DHEA in a similar manner to Ca(+2). We found that Mg(+2) was able to induce a conformational change in DHEA deviated from that of Ca(+2). These solid-state NMR observations indicate that DHEA is able to interact with cations, such as Mg(+2) and Ca(+2), with specificity.
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