Accessing real-time interaction between antimicrobial liposomes and live Staphylococcus epidermidis using surface...

Area of Science:

• Microbiology
• Biochemistry
• Medical Technology

Background:

• Staphylococcus epidermidis (SE) is a primary cause of healthcare-associated infections (HAIs) due to biofilm formation and antibiotic resistance.
• The antimicrobial mechanisms of cholesteryl linoleate (CL), a lipid with known activity against SE, are not well understood.
• Understanding SE-CL interactions is crucial for developing novel anti-infective strategies.

Purpose of the Study:

• To visualize and characterize the real-time interaction between cholesteryl linoleate (CL) and live Staphylococcus epidermidis (SE) cells.
• To investigate the binding kinetics and spatial distribution of CL on SE surfaces.
• To establish a novel microscopy protocol for studying antimicrobial-lipid interactions with live bacteria.

Main Methods:

• Development of a surface plasmon resonance microscopy (SPRm) protocol.
• Observation of live, stationary-phase SE cells interacting with CL formulated in phospholipid (CL-PL) liposomes.
• Buffer control experiments to ensure bacterial viability during SPRm analysis.

Main Results:

• Cholesteryl linoleate (CL) directly binds to the surface of Staphylococcus epidermidis (SE).
• CL-PL binding to SE is concentration-dependent and significantly stronger than phospholipid (PL) alone.
• Binding patterns are heterogeneous across SE cell surfaces, reflecting variations within the bacterial population.

Conclusions:

• Cholesteryl linoleate (CL) exhibits direct antimicrobial interaction with Staphylococcus epidermidis (SE).
• The developed SPRm method effectively visualizes real-time, heterogeneous antimicrobial binding to live bacteria.
• CL and similar lipids show promise for combating antibiotic-resistant SE and other HAIs pathogens.