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Isolation of Lipoprotein Particles from Chicken Egg Yolk for the Study of Bacterial Pathogen Fatty Acid Incorporation into Membrane Phospholipids
Published on: May 15, 2019
Saturated fatty acids enhance daptomycin activity in a Fak-dependent manner in enterococci
Sudan Maharjan1, Troy A Getty1, Quiana Dickens1
1Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA.
Microbiology (Reading, England)
|August 6, 2026
Summary
Adding saturated fatty acids like myristic and palmitic acid enhances daptomycin antibiotic effectiveness against resistant enterococci. This strategy improves bacterial susceptibility by altering membrane composition.
Area of Science:
- Microbiology
- Molecular Biology
- Drug Discovery
Background:
- Antibiotic resistance in Gram-positive bacteria, including enterococci, presents a significant clinical challenge.
- Daptomycin is a crucial lipopeptide antibiotic for treating infections caused by drug-resistant Gram-positive pathogens.
- Emerging daptomycin resistance and tolerance in clinical settings necessitate strategies to restore antibiotic efficacy.
Purpose of the Study:
- To investigate the potential of exogenous saturated fatty acids to enhance daptomycin activity against enterococcal strains.
- To elucidate the mechanisms by which fatty acids modulate bacterial membrane properties and daptomycin susceptibility.
Main Methods:
- Treatment of enterococcal strains with daptomycin in combination with saturated fatty acids (myristic acid, palmitic acid).
- Assessment of bacterial susceptibility to daptomycin using various microbiological assays.
- Analysis of bacterial membrane properties, including fluidity, permeability, and depolarization.
- Genetic manipulation of enterococcal strains to assess the role of fatty acid incorporation into phospholipids.
Main Results:
- Myristic and palmitic acids significantly increased daptomycin susceptibility in enterococci, including a daptomycin-resistant isolate.
- These effects were specific to enterococci, with no observed impact on *Staphylococcus aureus* susceptibility.
- Fatty acid treatment reduced membrane fluidity and caused depolarization, but did not alter membrane permeability.
- The potentiation effect was dependent on the ability of the bacteria to incorporate exogenous fatty acids into their phospholipids.
Conclusions:
- Specific saturated fatty acids can restore daptomycin susceptibility in resistant enterococci by altering membrane lipid composition and organization.
- Fatty acid incorporation into phospholipids is essential for this observed potentiation effect.
- This approach offers a potential strategy to combat daptomycin resistance in enterococcal infections by modulating bacterial membrane homeostasis.
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