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Updated: Jun 12, 2026
08:15
Membrane Remodeling of Giant Vesicles in Response to Localized Calcium Ion Gradients
Published on: July 16, 2018
[Study on the mechanism of Ca2+-buffering by sodium glycodeoxycholate micelles]
Hu-He Chen1, Fang-Ting Yu, Zhan-Lan Yang
1College of Chemistry and Molecular Engineering, State Key Laboratory of Rare Earth Material Chemistry and Application, Peking University, Beijing 100871, China.
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|May 26, 2010
Summary
Sodium glycodeoxycholate (NaGDC) micelles effectively buffer calcium ions (Ca2+). Increasing NaGDC concentration enhances this Ca2+ buffering capability, forming larger micellar structures.
Area of Science:
- Biochemistry
- Colloid Science
Context:
- Bile salt micelles play a role in biological systems.
- Understanding calcium ion interactions with bile salts is crucial.
Purpose:
- To investigate the Ca2+-buffering capability of sodium glycodeoxycholate (NaGDC) micelles.
- To elucidate the mechanism of Ca2+ buffering by NaGDC.
Summary:
- NaGDC, a major bile salt, was studied for its Ca2+-buffering properties using turbidity titration, QELS, TEM, and FTIR.
- Above the critical micelle concentration (CMC), NaGDC micelles buffer Ca2+ precipitation, with buffering capacity increasing with NaGDC concentration.
- At concentrations above CMC, Ca2+ bridges connect NaGDC micelles, forming larger fibriform micelles, and specific Na(n)Ca(m)(GDC)(n+2m) complexes precipitate at fixed Ca2+/Na+ ratios.
Impact:
- Provides insights into the interaction between bile salts and calcium ions.
- Contributes to understanding the physiological role of bile salts in calcium homeostasis.
- The findings may have implications for conditions involving bile salt and calcium metabolism.
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