Antimicrobial Fatty Acids and Bacterial Resistance Mechanisms

Antimicrobial fatty acids are medium- to long-chain carboxylic acids produced by hosts, commensals and dietary sources that inhibit bacterial pathogens through a range of mechanisms. By inserting into bacterial membranes they disrupt bilayer integrity, alter fluidity and permeability, and perturb essential processes such as energy generation and cell-wall synthesis. Certain fatty acids also serve as signalling molecules, binding to regulatory proteins and suppressing expression of virulence factors or biofilm formation. In response, bacteria have evolved diverse resistance strategies. Altering membrane lipid composition—shifting towards saturated or branched-chain fatty acids—reduces susceptibility to membrane-active lipids. Enzymatic modification or degradation of fatty acids, active efflux via transport pumps and induction of stress response regulons further enhance survival. These adaptive traits can cross-protect against conventional antibiotics, complicating the treatment of multidrug-resistant infections.

There is growing interest in harnessing antimicrobial fatty acids as therapeutic agents or antibiotic adjuvants. Applications span from topical and food-safety formulations to coatings for medical devices. Deeper understanding of how fatty acid structure interacts with bacterial resistance mechanisms and host defence pathways will be essential to guide the design of next-generation anti-infectives with broad-spectrum activity and low resistance potential.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Antimicrobial Fatty Acids and Bacterial Resistance Mechanisms publication trend

The graph below shows the total number of articles in antimicrobial fatty acids and bacterial resistance mechanisms across all publications each year (not limited to Nature Index journals).

Technical terms

Free fatty acids (FFAs): Unesterified carboxylic acids that insert into bacterial membranes and exert antimicrobial effects.

Critical micelle concentration (CMC): The lowest concentration at which amphiphilic molecules self-assemble into micelles in solution.

Krafft temperature: The temperature above which ionic surfactants become soluble enough to form micelles.

Lipid II: A peptidoglycan precursor in bacterial cell-wall synthesis targeted by antibiotics and synergistic lipids.

Adjuvant: A compound that, when combined with an antibiotic, enhances its antimicrobial activity.

Membrane fluidity: The viscosity of the lipid bilayer affecting protein mobility and membrane function.

Virulence factors: Pathogen-derived molecules that promote host colonisation, immune evasion and tissue damage.

Efflux pumps: Transport proteins that expel toxic compounds, including antimicrobial lipids, from bacterial cells.

References

1. Anti-infective activities of long-chain fatty acids against foodborne pathogens. FEMS Microbiology Reviews (2023).
2. Influence of critical micelle concentration of choline-based long chain fatty acid soaps on their antibacterial activity against Methicillin resistant Staphylococcus aureus. Journal of Colloid and Interface Science (2024).
3. Antibiotic-induced accumulation of lipid II synergizes with antimicrobial fatty acids to eradicate bacterial populations. eLife (2023).
4. Antibacterial fatty acids: An update of possible mechanisms of action and implications in the development of the next-generation of antibacterial agents. Progress in Lipid Research (2021).