Share Email Print

Proceedings Paper • new

Photo-disassembly of membrane microdomains revives a broad spectrum of antibiotics against MRSA persisters (Conference Presentation)

Paper Abstract

The prevalence of antibiotic resistance and the presence of bacterial persisters increasingly challenge the successful treatment of Staphylococcus aureus infections, and thus poses a great threat to the global health. Here, we present a photonic approach to revive a broad spectrum of antibiotics for eradication of MRSA persisters via photo-disassembly of functional membrane microdomains. Membrane microdomains on MRSA cells are enriched in staphyloxanthin-derived lipids as constituent lipids with co-localized and oligomerized multimeric protein complexes including PBP2a to execute various cellular processes and cell virulence. We demonstrated that the membrane-bound staphyloxinthin is prone to photobleaching by blue light due to triplet-triplet annihilation and thus compromises the membrane integrity. Using high-intensity 460 nm pulsed laser (wide-field illumination, dosage far below human safety limit), we achieved strikingly high staphyloxanthin bleaching efficiency and depth when compared to low-level light sources (quantified by resonance Raman spectroscopy). More importantly, such efficient and selective photolysis of constituent lipids leads to catastrophic disassembly of membrane microdomains, yielding highly compromised cell membrane with nanometer-scale pores created and PBP2a unanchored from cell membrane or dispersed (proved and quantified by immunofluorescence, fluorescence assay, confocal, super-resolution imaging, and Western blotting). The disruption renders MRSA persisters highly traumatized, thus no longer in dormant state (verified by stimulated Raman scattering microscopy). Consequently, cells with compromised membrane are found highly susceptible to a broad spectrum of antibiotics: beta-lactam antibiotics, such as penicillin and cephalosporins, due to PBP2a disassembly; antibiotics that inhibit intracellular activities enabled by effective diffusion via nanometer-scale pores, such as quinolones, aminoglycosides and sulfonamides. These synergistic therapies are validated both in vitro and in clinically relative models including biofilm and mice skin infection model. Collective, our findings unveil the underlying mechanism of photo-disassembly of MRSA membrane microdomains and highlight this photonic approach as a novel platform to revive a broad spectrum of conventional antibiotics and guide the development of new antibiotics for treatment of MRSA infections.

Paper Details

Date Published: 4 March 2019
Proc. SPIE 10863, Photonic Diagnosis and Treatment of Infections and Inflammatory Diseases II, 108630V (4 March 2019); doi: 10.1117/12.2509497
Show Author Affiliations
Jie Hui, Boston Univ. (United States)
Pu-Ting Dong, Boston Univ. (United States)
Junjie Li, Boston Univ. (United States)
Lijia Liang, Boston Univ. (United States)
Cheng Zong, Boston Univ. (United States)
Ji-Xin Cheng, Boston Univ. (United States)

Published in SPIE Proceedings Vol. 10863:
Photonic Diagnosis and Treatment of Infections and Inflammatory Diseases II
Tianhong Dai; Jürgen Popp; Mei X. Wu M.D., Editor(s)

© SPIE. Terms of Use
Back to Top