SC5005 dissipates the membrane potential to kill Staphylococcus aureus persisters without detectable resistance

Abstract

Objectives In the past few decades, multiple-antibiotic-resistant Staphylococcus aureus has emerged and quickly spread in hospitals and communities worldwide. Additionally, the formation of antibiotic-tolerant persisters and biofilms further reduces treatment efficacy. Previously, we identified a sorafenib derivative, SC5005, with bactericidal activity against MRSA in vitro and in vivo. Here, we sought to elucidate the resistance status, mode of action and anti-persister activity of this compound. Methods The propensity of S. aureus to develop SC5005 resistance was evaluated by assessment of spontaneous resistance and by multi-passage selection. The mode of action of SC5005 was investigated using macromolecular synthesis, LIVE/DEAD and ATPlite assays and DiOC2(3) staining. The effect of SC5005 on the mammalian cytoplasmic membrane was measured using haemolytic and lactate dehydrogenase (LDH) assays and flow cytometry. Results SC5005 depolarized and permeabilized the bacterial cytoplasmic membrane, leading to reduced ATP production. Because of this mode of action, no resistance of S. aureus to SC5005 was observed after constant exposure to sub-lethal concentrations for 200 passages. The membrane-perturbing activity of SC5005 was specific to bacteria, as no significant haemolysis or release of LDH from human HT-29 cells was detected. Additionally, compared with other bactericidal antibiotics, SC5005 exhibited superior activity in eradicating both planktonic and biofilm-embedded S. aureus persisters. Conclusions Because of its low propensity for resistance development and potent persister-eradicating activity, SC5005 is a promising lead compound for developing new therapies for biofilm-related infections caused by S. aureus.

Purine metabolism regulates Vibrio splendidus persistence associated with protein aggresome formation and intracellular tetracycline efflux

“…Also, the membrane potential and transmembrane proton pH gradient have an important compensation mechanism in the bacterial membrane ( Martins et al, 2009 ). We found that inhibition of purine metabolism was associated with a higher membrane potential as a result of dissipation of the transmembrane proton pH gradient, thus the concentration of tetracycline was reduced ( Figure 6 ), which was consistent with results from drug-resistance bacteria of E. coli and S. aureus ( Hards et al, 2018 ; Lu et al, 2021 ). In addition, pH can be altered by antibiotics by regulating H + /K + ions ( Hards et al, 2018 ; Lu et al, 2021 ).…”

“…We found that inhibition of purine metabolism was associated with a higher membrane potential as a result of dissipation of the transmembrane proton pH gradient, thus the concentration of tetracycline was reduced ( Figure 6 ), which was consistent with results from drug-resistance bacteria of E. coli and S. aureus ( Hards et al, 2018 ; Lu et al, 2021 ). In addition, pH can be altered by antibiotics by regulating H + /K + ions ( Hards et al, 2018 ; Lu et al, 2021 ). Similarly, the pH gradually decreased with the increase of the concentration of tetracycline or 6-MP in our study ( Figures 6C , D ).…”

“…Antibiotics tend to achieve a lower intracellular concentration in E. coli persistence cell, indicating either lower rate of drug uptake or higher rate of drug efflux, or a combination of both ( Alekshun and Levy, 2007 ; Pages et al, 2008 ; Pu et al, 2016 , 2017 ; Lu et al, 2021 ). The antibiotic accumulation of gram-negative bacteria is mainly affected by two factors of membrane permeability and efflux activity ( Pu et al, 2016 ).…”

Antibacterial Activity of Juglone Revealed in a Wound Model of Staphylococcus aureus Infection

“…Studies have shown that the fluorescence intensity of cell membrane decreased after ginger essential oil (GEO) treatment of bacterial cells, indicating that hyperpolarization of cell membrane leads to a decrease in cell metabolic activity. The study by Lu et al showed that the sorafenib derivative, SC5005, shows bactericidal activity against MRSA in vivo and in vitro by dissipating membrane potential and does not induce resistance in the strain [ 25 ]. Consistent with our findings, juglone significantly reduced the membrane potential of S. aureus , resulting in the hypertrophy of bacterial cells, which in turn damaged the integrity of the cell membrane.…”

Targeting the Achilles’ Heel of Multidrug-Resistant Staphylococcus aureus by the Endocannabinoid Anandamide

“…Membrane depolarization has been shown to affect the membrane distribution of cell division proteins [ 111 ], increase the susceptibility to antibiotics [ 73 ], and impede biofilm formation [ 112 ]. The LytSR regulatory system induces the transcription of the lrgAB operon in response to membrane depolarization [ 113 ], and the antiholin-like protein LrgA in turn inhibits autolysis [ 114 ].…”