Effect of naturally isolated hydroquinone in disturbing the cell membrane integrity of Pseudomonas aeruginosa MTCC 741 and Staphylococcus aureus MTCC 740

ABSTRACT In this issue of Journal of Bacteriology, Price et al. show that the Pseudomonas aeruginosa-produced exopolysaccharide alginate protects Staphylococcus aureus by dampening the expression of P. aeruginosa virulence products that usually inhibit S. aureus respiration and cell membrane integrity when the two organisms compete in other environments (C. E. Price, D. G. Brown, D. H. Limoli, V. V. Phelan, and G. A. O’Toole, J Bacteriol 202:e00559-19, 2020, https://doi.org/10.1128/jb.00559-19). This is the first report that exogenously added alginate affects P. aeruginosa competition and provides a partial explanation for S. aureus and P. aeruginosa coinfections in cystic fibrosis.

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Altering the Proclivity towards Daptomycin Resistance in Methicillin-Resistant Staphylococcus aureus Using Combinations with Other Antibiotics

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00502-12 ◽

2012 ◽

Vol 56 (10) ◽

pp. 5046-5053 ◽

Cited By ~ 40

Author(s):

Andrew D. Berti ◽

Justine E. Wergin ◽

Gary G. Girdaukas ◽

Scott J. Hetzel ◽

George Sakoulas ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Cell Wall ◽

Cell Membrane ◽

Membrane Integrity ◽

Wall Thickening ◽

Methicillin Resistant ◽

Content Type ◽

Cell Membrane Integrity ◽

Cell Membrane Fluidity

ABSTRACTDaptomycin (DAP) is increasingly used as a part of combination therapy, particularly in complex methicillin-resistantStaphylococcus aureus(MRSA) infections. While multiple studies have reported the potential for synergy between DAP and adjunctive anti-infectives, few have examined the influence of adjunctive therapy on the emergence of DAP resistance. This study examined eight adjunctive antimicrobial combinations with DAPin vitroand the emergence of DAP resistance over time (up to 4 weeks) using clinical isolates of DAP-susceptible MRSA (MIC, 0.5 μg/ml) in which DAP resistance subsequently developed during patient therapy (MIC, 3 μg/ml). In addition to DAP susceptibility testing, selected strains were examined for phenotypic changes associated with DAP resistance, including changes to cell wall thickness (CWT) and cell membrane alterations. The addition of either oxacillin or clarithromycin in medium containing DAP significantly inhibited the development of DAP resistance through the entirety of the 4-week exposure (10- to 32-fold MIC reduction from that of DAP alone). Combinations with rifampin or fosfomycin were effective in delaying the emergence of DAP resistance through the end of week one only (week one MIC, 0.5 μg/ml; week four MIC, 24 μg/ml). Cell wall thickening was observed for all antibiotic combinations regardless of their effect on the DAP MIC (14 to 70% increase in CWT), while changes in cell membrane fluidity were variable and treatment dependent. DAP showed reduced activity against strains with DAP MICs of 1 to 12 μg/ml, but cell membrane integrity was still disrupted at concentrations achieved with doses greater than 10 mg/kg of body weight. The emergence of DAP resistance in MRSA is strongly influenced by the presence of subinhibitory concentrations of adjunctive antimicrobials. These data suggest that combining DAP with oxacillin or clarithromycin may delay the development of DAP resistance in cases requiring prolonged antibiotic therapy.

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Effect of Bacoside A on growth and biofilm formation by Staphylococcus aureus and Pseudomonas aeruginosa

Canadian Journal of Microbiology ◽

10.1139/cjm-2016-0365 ◽

2017 ◽

Vol 63 (2) ◽

pp. 169-178 ◽

Cited By ~ 11

Author(s):

Debaprasad Parai ◽

Ekramul Islam ◽

Jayati Mitra ◽

Samir Kumar Mukherjee

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Cell Membrane ◽

Extracellular Polymeric Substances ◽

Inhibitory Concentration ◽

Membrane Integrity ◽

Bacterial Biofilm ◽

Antibiofilm Activity ◽

Bacoside A ◽

Microscopic Studies

The goal of this study was to evaluate the antibiofilm and antimicrobial activities of Bacoside A, a formulation of phytochemicals from Bacopa monnieri, against Staphylococcus aureus and Pseudomonas aeruginosa, which are known to form biofilms as one of their virulence traits. The antimicrobial effects of Bacoside A were tested using the minimum inhibitory concentration and minimum bactericidal concentration assays. A cell membrane disruption assay was performed to find its possible target site. MTT assay, crystal violet assay, and microscopic studies were performed to assess the antibiofilm activity. Bacoside A showed antimicrobial activity against both test organisms in their planktonic and biofilm states. At a subminimum inhibitory concentration of 200 μg·mL−1, Bacoside A significantly removed ∼88%–93% of bacterial biofilm developed on microtiter plates. Biochemical and microscopic studies suggested that the eradication of biofilm might be due to the loss of extracellular polymeric substances and to a change in cell membrane integrity of the selected bacterial strains treated with Bacoside A. These results indicate that Bacoside A might be considered as an antimicrobial having the ability to disrupt biofilms. Thus, either alone or in combination with other therapeutics, Bacoside A could be useful to treat biofilm-related infections caused by opportunistic bacterial pathogens.

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N-acetyl Cysteine Coated Gallium Particles Demonstrate High Potency against Pseudomonas aeruginosa PAO1

Pathogens ◽

10.3390/pathogens8030120 ◽

2019 ◽

Vol 8 (3) ◽

pp. 120 ◽

Cited By ~ 1

Author(s):

Young ◽

Ozcan ◽

Lee ◽

Maxwell ◽

Andl ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Cell Membrane ◽

Inductively Coupled Plasma ◽

Bacterial Resistance ◽

Membrane Integrity ◽

The United States ◽

Therapeutic Window ◽

Pseudomonas Aeruginosa Pao1 ◽

Cell Membrane Integrity ◽

Acetyl Cysteine

Nosocomial infections pose serious health concerns with over 2 million reported annually in the United States. Many of these infections are associated with bacterial resistance to antibiotics and hence, alternative treatments are critically needed. The objective of this study was to assess the antimicrobial efficacy of a gallium (Ga)-based particle coated with N-Acetyl Cysteine (Ga-NAC) against Pseudomonas aeruginosa PAO1. Our studies showed the Minimum Inhibitory Concentration (MIC) of PAO1 treated with Ga-NAC was 1 µg/mL. Cytotoxicity of Ga-NAC against multiple cell lines was determined with no cytotoxicity observed up to concentrations of 2000 µg/mL (metal concentration), indicating a high therapeutic window. To elucidate potential antibacterial modes of action, Inductively Coupled Plasma—Mass Spectrometry (ICP-MS), infrared spectroscopy, and atomic force microscopy (AFM) were used. The results suggest improved Ga3+ interaction with PAO1 through Ga-NAC particles. No significant change in cell membrane chemistry or roughening was detected. As cell membrane integrity remained intact, the antimicrobial mode of action was linked to cellular internalization of Ga and subsequent iron metabolic disruption. Furthermore, Ga-NAC inhibited and disrupted biofilms seen with crystal violet assay and microscopy. Our findings suggest the Ga-NAC particle can potentially be used as an alternative to antibiotics for treatment of Pseudomonas aeruginosa infections.

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Anthracycline Shunt Metabolites From Philippine Marine Sediment-Derived Streptomyces Destroy Cell Membrane Integrity of Multidrug-Resistant Staphylococcus aureus

Frontiers in Microbiology ◽

10.3389/fmicb.2020.00743 ◽

2020 ◽

Vol 11 ◽

Cited By ~ 1

Author(s):

Melissa June V. Paderog ◽

Angelica Faith L. Suarez ◽

Edna M. Sabido ◽

Zhen Jie Low ◽

Jonel P. Saludes ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Cell Membrane ◽

Marine Sediment ◽

Membrane Integrity ◽

Multidrug Resistant ◽

Cell Membrane Integrity

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Contractile Reserve, Microvascular Integrity and Cell Membrane Integrity for Predicting Contractile Recovery After Recanalization in Acute Myocardial Infarction

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(97)84062-4 ◽

1998 ◽

Vol 31 (2) ◽

pp. 81A-82A

Author(s):

J Kwan

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Cell Membrane ◽

Membrane Integrity ◽

Contractile Reserve ◽

Cell Membrane Integrity ◽

Contractile Recovery

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Quercetin in attenuation of ischemic/reperfusion injury: A review

Current Molecular Pharmacology ◽

10.2174/1874467213666201217122544 ◽

2020 ◽

Vol 13 ◽

Author(s):

Milad Ashrafizadeh ◽

Saeed Samarghandian ◽

Kiavash Hushmandi ◽

Amirhossein Zabolian ◽

Md Shahinozzaman ◽

...

Keyword(s):

Cell Death ◽

Cell Membrane ◽

Blood Supply ◽

Apoptotic Cell ◽

Ischemia Reperfusion ◽

Membrane Integrity ◽

Therapeutic Effects ◽

Molecular Pathways ◽

Cell Membrane Integrity ◽

Cell Membrane Disruption

Background: Ischemia/reperfusion (I/R) injury is a serious pathologic event that occurs due to restriction in blood supply to an organ, followed by hypoxia. This condition leads to enhanced levels of pro-inflammatory cytokines such as IL-6 and TNF-, and stimulation of oxidative stress via enhancing reactive oxygen species (ROS) levels. Upon reperfusion, blood supply increases, but it deteriorates condition, and leads to generation of ROS, cell membrane disruption and finally, cell death. Plant derived-natural compounds are well-known due to their excellent antioxidant and anti-inflammatory activities. Quercetin is a flavonoid exclusively found in different vegetables, herbs, and fruits. This naturally occurring compound possesses different pharmacological activities making it appropriate option in disease therapy. Quercetin can also demonstrate therapeutic effects via affecting molecular pathways such as NF-B, PI3K/Akt and so on. Methods: In the present review, we demonstrate that quercetin administration is beneficial in ameliorating I/R injury via reducing ROS levels, inhibition of inflammation, and affecting molecular pathways such as TLR4/NF-B, MAPK and so on. Results and conclusion: Quercetin can improve cell membrane integrity via decreasing lipid peroxidation. Apoptotic cell death is inhibited by quercetin via down-regulation of Bax, and caspases, and upregulation of Bcl-2. Quercetin is able to modulate autophagy (inhibition/induction) in decreasing I/R injury. Nanoparticles have been applied for delivery of quercetin, enhancing its bioavailability and efficacy in alleviation of I/R injury. Noteworthy, clinical trials have also confirmed the capability of quercetin in reducing I/R injury.

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