The product of the qacC gene of Staphylococcus epidermidis CH mediates resistance to β-lactam antibiotics in Gram-positive and Gram-negative bacteria

Fuentes, Derie E.; Navarro, C.; Tantaleán, Juan C.; Araya, Manuel A.; Saavedra, Claudia P.; Pérez, Jose; Calderón, Iván L.; Youderian, Phil A.; Mora, Gabriela; Vásquez, Claudio C.

doi:10.1016/j.resmic.2005.01.002

Cited by 35 publications

(23 citation statements)

References 15 publications

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“…S. epidermidis CH is resistant to high levels of tellurite, as well as to the salts of many other heavy metals. The minimal inhibitory concentration of tellurite for this microbe is 0.5 mM (150 µg/ml), 100-fold greater than that for the model eubacterium E. coli (1.5 µg/ml) [29]. To understand the biochemical basis for this resistance, we prepared cell-free extracts from S. epidermidis CH, and found that these extracts have an activity that catalyzes the reduction of K 2 TeO 3 , dependent on the presence of NADH (Fig.…”

Section: Resultsmentioning

confidence: 74%

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Catalases Are NAD(P)H-Dependent Tellurite Reductases

et al. 2006

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Reactive oxygen species damage intracellular targets and are implicated in cancer, genetic disease, mutagenesis, and aging. Catalases are among the key enzymatic defenses against one of the most physiologically abundant reactive oxygen species, hydrogen peroxide. The well-studied, heme-dependent catalases accelerate the rate of the dismutation of peroxide to molecular oxygen and water with near kinetic perfection. Many catalases also bind the cofactors NADPH and NADH tenaciously, but, surprisingly, NAD(P)H is not required for their dismutase activity. Although NAD(P)H protects bovine catalase against oxidative damage by its peroxide substrate, the catalytic role of the nicotinamide cofactor in the function of this enzyme has remained a biochemical mystery to date. Anions formed by heavy metal oxides are among the most highly reactive, natural oxidizing agents. Here, we show that a natural isolate of Staphylococcus epidermidis resistant to tellurite detoxifies this anion thanks to a novel activity of its catalase, and that a subset of both bacterial and mammalian catalases carry out the NAD(P)H-dependent reduction of soluble tellurite ion (TeO3 2−) to the less toxic, insoluble metal, tellurium (Te°), in vitro. An Escherichia coli mutant defective in the KatG catalase/peroxidase is sensitive to tellurite, and expression of the S. epidermidis catalase gene in a heterologous E. coli host confers increased resistance to tellurite as well as to hydrogen peroxide in vivo, arguing that S. epidermidis catalase provides a physiological line of defense against both of these strong oxidizing agents. Kinetic studies reveal that bovine catalase reduces tellurite with a low Michaelis-Menten constant, a result suggesting that tellurite is among the natural substrates of this enzyme. The reduction of tellurite by bovine catalase occurs at the expense of producing the highly reactive superoxide radical.

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Section: Resultsmentioning

confidence: 74%

“…S. epidermidis CH cells were grown in LB medium containing erythromycin (50 µg/ml) at 37°C as described [29]. Cells were collected by centrifugation at 4,500× g for 10 min, washed, and suspended in PBG buffer (20 mM potassium phosphate pH 7.0, 1 mM 2-mercaptoethanol, 5% glycerol) at a ratio of 2 ml PBG buffer/g of cell paste.…”

Section: Methodsmentioning

confidence: 99%

Catalases Are NAD(P)H-Dependent Tellurite Reductases

et al. 2006

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“…Furthermore, for qacC it was shown that it confers resistance to a number of b-lactam antibiotics (Fuentes et al 2005). Cross-resistance between biocides and antibiotics could also be caused by cell wall modifications, reducing its permeability (European Commission 2009;Fraise 2011).…”

Section: Role Of Qaacs In the Selection Of Antibiotic Resistancementioning

confidence: 99%

Quaternary ammonium compounds in soil: implications for antibiotic resistance development

Mulder

Siemens

Sentek

et al. 2017

Rev Environ Sci Biotechnol

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Quaternary ammonium compounds (QACs) are surface-active, antimicrobial, high production volume (HPV) chemicals with a broad application in agriculture. This review provides a comprehensive overview of (1) predicted and measured concentrations of QACs in soils including their analysis, (2) sequestration mechanisms in soils based on their physicochemical properties and chemical structure, and (3) implications of concentrations and fate of QACs in soils for the proliferation of antibiotic resistance in the environment. Predicted environmental concentrations (PEC) for QACs that are applied to soils with manure are in the order of 3.5 mg kg -1 . Based on literature data, the median PEC of QAC in sewage sludge amended soils is 25 lg kg -1 . The positively charged QACs are mainly sorbed to clay minerals. We propose that QACs might be sequestered in the interlayer regions of layered silicates in clayrich soils, reducing their acute toxicity, while increasing their persistence. The release of sequestered QACs from soil can still potentially maintain concentration levels that are sufficient to develop antibiotic resistance in the environment.

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“…QacC confers resistance to a range of monovalent cationic antimicrobials, such as Qacs and various dyes ( table 2 ). Surprisingly, it has also been reported that QacC confers resistance to ␤ -lactam antibiotics, which prevent bacterial cell wall synthesis [Fuentes et al, 2005]. Since the efflux of ␤ -lactams by QacC would effectively increase the concentration of these antibiotics at their target site, direct evidence for QacC-mediated transport of ␤ -lactams is required before it is concluded that the observed resistance is efflux related.…”

Section: Qaccmentioning

confidence: 99%

Active Export Proteins Mediating Drug Resistance in Staphylococci

2007

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Drug resistance mediated by integral membrane transporters is an important mode of cellular resistance to cytotoxic agents across all classes of living organisms. Gram-positive bacteria, such as staphylococcal species, are not encapsulated by a selective outer membrane permeability barrier. Therefore, these organisms often employ integral membrane drug transport systems to maintain cellular concentrations of antimicrobials at subtoxic levels. Staphylococcal species, including the opportunistic human pathogen Staphylococcus aureus, encode a multitude of drug exporters, encompassing transporters from each of the five currently recognized families of bacterial drug resistance transporters. A number of these transporters are chromosomally encoded and allow the host cell to realize clinically significant levels of drug resistance after minor mutations to regulatory regions. Others are plasmid-encoded and can be easily passed between staphylococcal strains and species, or acquired from other Gram-positive genera. In combination, staphylococcal drug transporters potentiate resistance to a vast array of antimicrobial compounds, including macrolide, quinolone, tetracycline and streptogramin antibiotics, as well as a broad range of biocides, such as quaternary ammonium compounds, biguanidines and diamidines. An understanding of the genetic and molecular properties of drug transporters will lead to effective treatments of staphylococcal infections. Here we provide a detailed review of the active drug transporters of the staphylococci.

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The product of the qacC gene of Staphylococcus epidermidis CH mediates resistance to β-lactam antibiotics in Gram-positive and Gram-negative bacteria

Cited by 35 publications

References 15 publications

Catalases Are NAD(P)H-Dependent Tellurite Reductases

Catalases Are NAD(P)H-Dependent Tellurite Reductases

Quaternary ammonium compounds in soil: implications for antibiotic resistance development

Active Export Proteins Mediating Drug Resistance in Staphylococci

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