Synergistic antibacterial activity of gold nanoparticles caused by apoptosis‐like death

Abstract

Aims: Metal nanoparticles are promising materials for the management of infectious diseases as known to have various antimicrobial activities in pathogenic micro-organisms. Among them, gold nanoparticles (AuNPs) are used in a wide range of fields such as photodynamic therapy, molecular diagnostics and drug delivery because of their unique physicochemical properties. However, little is known about the synergistic antibacterial activity and mechanism of AuNPs on pathogenic bacteria. Methods and Results: Combinations of AuNPs and cefotaxime and ciprofloxacin showed synergistic interaction against all Salmonella species, however the combination with kanamycin exhibited no interaction. We determined that AuNPs and in combinations with antibiotics exert its antibacterial effect through bacterial apoptosis-like death. AuNPs caused collapse of intracellular divalent cation homeostasis, and conventional antibiotics caused accumulation of reactive oxygen species, which induced apoptotic hallmarks such as membrane depolarization, caspase-like protein activation, cell filamentation and phosphatidylserine externalization.

Varied-shaped gold nanoparticles with nanogram killing efficiency as potential antimicrobial surface coatings for the medical devices

“…2 ). Interestingly, in previously published reports the mechanism of AuNP-mediated killing was independent of reactive oxygen species formation, which is in contrast to data acquired in this research 52 . Nevertheless, it should be noted that in both of the reports referenced spherical gold nanoparticles were used, in contrast to the non-spherical ones used in this research.…”

Phytosynthesis of colloidal nanosilver from Mentha longifolia and Mentha arvensis: Comparative morphological and optical characterization

“…ROS results in the proteolytic cleavage of plasma cell membranes and the killing of cells. Some scientific reports established the presence of elemental O as a very important factor to generate ROS that contributes toward the cytotoxic and photodynamic potential of nanoparticles (Fani et al, 2016; Lee & Lee, 2019).…”

The Demand for New Antibiotics: Antimicrobial Peptides, Nanoparticles, and Combinatorial Therapies as Future Strategies in Antibacterial Agent Design

“…They can be used in combinatorial treatments with currently used antibiotics for enhanced antimicrobial activity ( Shahverdi et al, 2007 ; Kora and Rastogi, 2013 ; Naqvi et al, 2013 ; Singh et al, 2013 ; Panácek et al, 2016 ; Lopez-Carrizales et al, 2018 ; Perveen et al, 2018 ; Vazquez-Muñoz et al, 2019 ). Nonetheless, some other MNPs such as gold ( El-Sheekh and El Kassas, 2014 ; Kalita et al, 2016 ; Al-Mawlawi and Obaid, 2019 ; Arya et al, 2019 ; Lee and Lee, 2019 ; Nishanthi et al, 2019 ; Yang et al, 2019 ), copper ( Khurana et al, 2016 ; Woźniak-Budych et al, 2017 ; Murugan, 2018 ; Selvaraj et al, 2019 ), and zinc ( Banoee et al, 2010 ; Bhande et al, 2013 ) have been used in combination with a variety of antibiotic families to enhance bactericidal efficacy.…”