Work

Blue Light Compromises Bacterial β‐Lactamases Activity to Overcome β‐Lactam Resistance

Year: 2024

Type: article

Abstract: ABSTRACT Objective In this study, we evaluated the effectiveness of antimicrobial blue light (aBL; 410 nm wavelength) against β‐lactamase‐carrying bacteria and the effect of aBL on the activity of β‐lactamases. Methods Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae strains carrying β‐lactamases as well as a purified β‐lactamase enzymes were studied. β‐lactamase activity was assessed using a chromogenic cephalosporin hydrolysis assay. Additionally, we evaluated the role of porphyrins in the photoreaction, as well as protein degradation by sodium dodecyl‐sulfate polyacrylamide gel electrophoresis (SDS‐PAGE). Finally, we investigated the bactericidal effect of combined aBL‐ceftazidime exposure against a metallo‐β‐lactamase expressing P. aeruginosa strain. Results Our study demonstrated that aBL effectively killed β‐lactamase‐producing bacteria and reduced β‐lactamase activity. After an aBL exposure of 1.52 J/cm2, a 50% reduction in enzymatic activity was observed in P. aeruginosa. Additionally, we found a 40% decrease in the photoreaction activity of porphyrins following an aBL exposure of 64.8 J/cm2. We also revealed that aBL reduced β‐lactamase activity via protein degradation (after 136.4 J/cm2). Additionally, aBL markedly improved the bactericidal effect of ceftazidime (by >4‐log10) in the metallo‐β‐lactamase P. aeruginosa strain. Conclusion Our results provide evidence that aBL compromises bacterial β‐lactamase activity, offering a potential approach to overcome β‐lactam resistance in bacteria.

Source: Lasers in Surgery and Medicine

DOI: 10.1002/lsm.23819