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Updated: Apr 17, 2026
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Using Multi-fluorinated Bile Acids and In Vivo Magnetic Resonance Imaging to Measure Bile Acid Transport
Published on: November 27, 2016
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Structural and functional implications of the interaction between macrolide antibiotics and bile acids
Simon Glanzer1, Sergio A Pulido, Sarah Tutz
1Institute of Chemistry, University of Graz (Austria).
Chemistry (Weinheim an Der Bergstrasse, Germany)
|February 7, 2015
Summary
Macrolide antibiotics bind directly to bile acid micelles, a key interaction in the biliary system. This binding does not hinder antibiotic efficacy and may even enhance azithromycin
Area of Science:
- Pharmacology
- Biochemistry
- Physical Chemistry
Background:
- Macrolide antibiotics are widely used but interact with the biliary system.
- Their molecular-level interactions with bile acids are not well understood.
- Macrolides influence drug excretion and are linked to biliary diseases.
Purpose of the Study:
- To elucidate the molecular details of macrolide-bile acid interactions.
- To determine the binding topology and factors influencing this interaction.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy.
- Solvent paramagnetic relaxation enhancements (PREs) for topological analysis.
Main Results:
- Macrolides directly bind to bile acid micelles.
- Binding occurs near the micelle surface, influenced by hydrophobicity.
- No preferred orientation was observed for macrolides or bile acids within micelles.
- Bile presence slightly increased azithromycin toxicity against ETEC.
Conclusions:
- Macrolides interact directly with bile acid aggregates.
- This interaction is governed by hydrophobicity and occurs at the micelle surface.
- Bile interaction does not impair macrolide antibacterial activity and may enhance it.
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