Abstract: Methods of the present invention comprise photoinactivation of catalase in combination with low-concentration peroxide solutions and/or ROS generating agents to provide antibacterial effects.

Abstract: Methods of the present invention comprise photoinactivation of catalase in combination with low-concentration peroxide solutions and/or ROS generating agents to provide antibacterial effects.

Abstract: Methods of the present invention comprise photoinactivation of catalase in combination with low-concentration peroxide solutions and/or ROS generating agents to provide antibacterial effects.

Abstract: Methods of the present invention comprise photoinactivation of catalase in combination with low-concentration peroxide solutions and/or ROS generating agents to provide antibacterial effects.

Abstract: Methods of the present invention comprise photoinactivation of catalase in combination with low-concentration peroxide solutions and/or ROS generating agents to provide antibacterial effects.

Abstract: Methods of the present invention comprise photoinactivation of catalase in combination with low-concentration peroxide solutions and/or ROS generating agents to provide antibacterial effects.

Abstract: Methicillin-resistant Staphylococcus aureus (MRSA) possesses array of strategies to evade antibiotics through mutational inactivation, hiding inside host immune cells or concealing inside the biofilm in a sessile form. We report a drug-free approach to eradicate MRSA through blue-light bleaching of staphyloxanthin (STX), an anti-oxidative carotenoid residing inside the cell membrane of S. aureus. The photobleaching process, uncovered through a transient absorption imaging study and quantitated by mass spectrometry, decomposes STX and sensitizes MRSA to reactive oxygen species attack. Consequently, photobleaching using low-level blue light exhibits high-level synergy when combined with low-concentration of hydrogen peroxide. Antimicrobial effectiveness of this synergistic therapy is validated in MRSA culture, MRSA-infected macrophage cells, biofilm, and a mouse wound infection model. Collectively, these findings highlight broad applications of STX photobleaching for MRSA-infected diseases.

Abstract: Methods of the present invention comprise photoinactivation of catalase in combination with low-concentration peroxide solutions and/or ROS generating agents to provide antibacterial effects.

Abstract: Confronted with the rapid evolution and dissemination of antibiotic resistance, there is an urgent need to develop alternative treatment strategies for drug-resistant S. aureus, especially for methicillin-resistant S. aureus (MRSA). We report a photonic approach to eradicate MRSA through blue-light photolysis of staphyloxanthin (STX), an anti-oxidative carotenoid acting as the constituent lipid of the functional membrane microdomains of S. aureus. Our transient absorption imaging study and mass spectrometry unveil the photolysis process of STX. After effective STX photolysis by pulsed laser, cell membranes are found severely disorganized and malfunctioned to defense antibiotics, as unveiled by membrane permeabilization, membrane fluidification, and detachment of membrane protein, PBP2a.

Abstract: Methicillin-resistant Staphylococcus aureus (MRSA) possesses array of strategies to evade antibiotics through mutational inactivation, hiding inside host immune cells or concealing inside the biofilm in a sessile form. We report a drug-free approach to eradicate MRSA through blue-light bleaching of staphyloxanthin (STX), an anti-oxidative carotenoid residing inside the cell membrane of S. aureus. The photobleaching process, uncovered through a transient absorption imaging study and quantitated by mass spectrometry, decomposes STX and sensitizes MRSA to reactive oxygen species attack. Consequently, photobleaching using low-level blue light exhibits high-level synergy when combined with low-concentration of hydrogen peroxide. Antimicrobial effectiveness of this synergistic therapy is validated in MRSA culture, MRSA-infected macrophage cells, biofilm, and a mouse wound infection model. Collectively, these findings highlight broad applications of STX photobleaching for MRSA-infected diseases.