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Updated: Apr 18, 2026
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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
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Cation ion specifically induces a conformational change in trans-dehydroandrosterone - a solid-state NMR study
Darong Wang1, Meiman Chen1, Rong-Jie Chein1
1Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan, ROC.
Steroids
|February 1, 2015
Summary
Calcium (Ca+2) binding induces structural changes in trans-dehydroandrosterone (DHEA), as shown by solid-state NMR. This interaction is specific, with magnesium (Mg+2) causing a different conformational shift.
Area of Science:
- Biochemistry
- Structural Biology
- Spectroscopy
Background:
- Trans-dehydroandrosterone (DHEA) is a steroid hormone.
- Cation interactions with biomolecules can alter their structure and function.
Purpose of the Study:
- To investigate the effect of calcium (Ca+2) on the conformation of DHEA.
- To compare the interaction of Ca+2 with DHEA to that of magnesium (Mg+2).
Main Methods:
- Solid-state Carbon-13 Nuclear Magnetic Resonance (NMR) spectroscopy was employed.
- DHEA was incubated with varying concentrations of Ca+2 and Mg+2.
- Analysis of chemical shift isotropy and anisotropy.
Main Results:
- High-resolution 13C NMR spectra revealed two distinct signal sets for DHEA/Ca+2 mixtures, indicating complex formation.
- Ca+2 binding likely occurs at the oxygen on C17, inducing a conformational change.
- Mg+2 also induced a conformational change in DHEA, but distinct from that caused by Ca+2.
Conclusions:
- DHEA interacts with cations, specifically Ca+2 and Mg+2.
- The interaction leads to cation-specific conformational changes in DHEA.
- Solid-state NMR is a valuable tool for studying biomolecule-cation interactions.
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