title: Cation ion specifically induces a conformational change in trans-dehydroandrosterone - a solid-state NMR study.
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.
authors: Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan, ROC.
authors: Darong
authors: D
authors: Wang
authors: Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan, ROC.
authors: Meiman
authors: M
authors: Chen
authors: Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan, ROC.
authors: Rong-Jie
authors: RJ
authors: Chein
authors: Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan, ROC.
authors: Wei-Min
authors: WM
authors: Ching
authors: Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan, ROC.
authors: Chen-Hsiung
authors: CH
authors: Hung
authors: Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan, ROC. Electronic address: tzougate@gate.sinica.edu.tw.
authors: Der-Lii M
authors: DL
authors: Tzou
mesh_terms: D002118:Calcium / Q000378:metabolism / Q000494:pharmacology*; D003687:Dehydroepiandrosterone / Q000737:chemistry* / Q000378:metabolism; D008274:Magnesium / Q000378:metabolism / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation / Q000187:drug effects*
chemical_list: D003687:Dehydroepiandrosterone; D008274:Magnesium; D002118:Calcium
keywords: Calcium; Cation ion; Conformational change; Magnesium; Steroidal ring conformation; trans-Dehydroandrosterone