Microbial growth on medical and technical devices is a big health issue, particularly when microo... more Microbial growth on medical and technical devices is a big health issue, particularly when microorganisms aggregate to form biofilms. Moreover, the occurrence of antibiotic-resistant bacteria in the clinical environment is dramatically growing, making treatment of bacterial infections very challenging. In search of an alternative, we studied a novel antimicrobial surface coating based on micro galvanic elements formed by silver and ruthenium with surface catalytic properties.
The antimicrobial coating efficiently inhibited the growth of the nosocomial pathogens Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium as demonstrated by the growth inhibition on agar surface and in biofilms of antibiotic resistant clinical E. faecalis, E. faecium, and S. aureus isolates. It also strongly reduced the growth of Legionella in a drinking water pipeline and of Escherichia coli in urine. We postulate a mode of action of the antimicrobial material, which is independent of the release of silver ions. Thus, the novel antimicrobial coating could represent an alternative to combat microbial growth avoiding the toxic side effects of high levels of silver ions on eukaryotic cells.
Wastewater contains large amounts of pharmaceuticals, pathogens, and antimicrobial resistance det... more Wastewater contains large amounts of pharmaceuticals, pathogens, and antimicrobial resistance determinants. Only a little is known about the dissemination of resistance determinants and changes in soil microbial communities affected by wastewater irrigation. Community DNAs from Mezquital Valley soils under irrigation with untreated wastewater for 0 to 100 years were analyzed by quantitative real-time PCR for the presence of sul genes, encoding resistance to sulfonamides. Amplicon sequencing of bacterial 16S rRNA genes from community DNAs from soils irrigated for 0, 8, 10, 85, and 100 years was performed and revealed a 14% increase of the relative abundance of Proteobacteria in rainy season soils and a 26.7% increase in dry season soils for soils irrigated for 100 years with wastewater. In particular, Gammaproteobacteria, including potential pathogens, such as Pseudomonas, Stenotrophomonas, and Acinetobacter spp., were found in wastewater-irrigated fields. 16S rRNA gene sequencing of...
Horizontal gene transfer (HGT) is an important means to obtain and maintain plasticity of microbi... more Horizontal gene transfer (HGT) is an important means to obtain and maintain plasticity of microbial genomes. Basically, bacteria apply three different modes to horizontally exchange genetic material: (1) conjugative transfer mediated by mobile genetic elements (MGE), (2) DNA uptake via transformation, and (3) transduction. The three modes rely on different prerequisites of the participating cells: conjugative transfer depends on close cell to cell contact between a donor and a recipient cell and is mediated through multi-protein complexes, denominated type IV secretion systems (T4SS), and DNA transformation does not rely on cell–cell contact but is the uptake of free DNA from the environment by a competent bacterial cell. In some bacteria it is also mediated by a T4SS. The third mechanism depends on the presence of a bacteriophage, which can transfer genomic DNA from one host cell to another. Experimental evidence exists that all three modes occur in planktonic cultures and recent data have also been provided for the occurrence of all three ways in biofilms. Regulation of these HGT events and their consequences for the acting microbes and the biofilms they live in are discussed in this chapter. Additionally, we focus on modern techniques to visualize and to quantify HGT in planktonic and biofilm modes.
Environmental Deterioration and Human Health-Natural and anthropogenic determinants, 2014
Antibiotic-resistant pathogenic bacteria pose a high threat to human health, but the environmenta... more Antibiotic-resistant pathogenic bacteria pose a high threat to human health, but the environmental reservoirs of resistance genes are poorly understood. The origins of antibiotic resistance in the environment are relevant to human health because of the increasing importance of zoonotic diseases as well as the requirement for predicting emerging resistant pathogens. Only little is known about the antibiotic resistomes of the great majority of environmental bacteria, although there have been calls for a greater understanding of the environmental reservoirs of antibiotic resistance. The data on antibiotic resistance before the antibiotic era and in soil show how far away we are from a complete picture about the ecology of antibiotic resistance genes (ARGs). Most of the natural antibiotic producers reside in soil, but soil is a particularly challenging habitat due to its chemical and physical heterogeneity. The prevalence and diversity of ARGs in the environment led to hypotheses about the native roles of resistance genes in natural microbial communities.
Journal of Liquid Chromatography & Related Technologies, Jan 1, 2010
We present a video-densitometric quantification method for the triazine herbicides atraton, terbu... more We present a video-densitometric quantification method for the triazine herbicides atraton, terbumeton, simazine, atrazine, and terbutylazine. Triazine herbicides were separated on silica gel using methyl-t-butyl ether, cyclohexane (1+ 1, v/v) as mobile phase. The ...
Microbial growth on medical and technical devices is a big health issue, particularly when microo... more Microbial growth on medical and technical devices is a big health issue, particularly when microorganisms aggregate to form biofilms. Moreover, the occurrence of antibiotic-resistant bacteria in the clinical environment is dramatically growing, making treatment of bacterial infections very challenging. In search of an alternative, we studied a novel antimicrobial surface coating based on micro galvanic elements formed by silver and ruthenium with surface catalytic properties.
The antimicrobial coating efficiently inhibited the growth of the nosocomial pathogens Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium as demonstrated by the growth inhibition on agar surface and in biofilms of antibiotic resistant clinical E. faecalis, E. faecium, and S. aureus isolates. It also strongly reduced the growth of Legionella in a drinking water pipeline and of Escherichia coli in urine. We postulate a mode of action of the antimicrobial material, which is independent of the release of silver ions. Thus, the novel antimicrobial coating could represent an alternative to combat microbial growth avoiding the toxic side effects of high levels of silver ions on eukaryotic cells.
Wastewater contains large amounts of pharmaceuticals, pathogens, and antimicrobial resistance det... more Wastewater contains large amounts of pharmaceuticals, pathogens, and antimicrobial resistance determinants. Only a little is known about the dissemination of resistance determinants and changes in soil microbial communities affected by wastewater irrigation. Community DNAs from Mezquital Valley soils under irrigation with untreated wastewater for 0 to 100 years were analyzed by quantitative real-time PCR for the presence of sul genes, encoding resistance to sulfonamides. Amplicon sequencing of bacterial 16S rRNA genes from community DNAs from soils irrigated for 0, 8, 10, 85, and 100 years was performed and revealed a 14% increase of the relative abundance of Proteobacteria in rainy season soils and a 26.7% increase in dry season soils for soils irrigated for 100 years with wastewater. In particular, Gammaproteobacteria, including potential pathogens, such as Pseudomonas, Stenotrophomonas, and Acinetobacter spp., were found in wastewater-irrigated fields. 16S rRNA gene sequencing of...
Horizontal gene transfer (HGT) is an important means to obtain and maintain plasticity of microbi... more Horizontal gene transfer (HGT) is an important means to obtain and maintain plasticity of microbial genomes. Basically, bacteria apply three different modes to horizontally exchange genetic material: (1) conjugative transfer mediated by mobile genetic elements (MGE), (2) DNA uptake via transformation, and (3) transduction. The three modes rely on different prerequisites of the participating cells: conjugative transfer depends on close cell to cell contact between a donor and a recipient cell and is mediated through multi-protein complexes, denominated type IV secretion systems (T4SS), and DNA transformation does not rely on cell–cell contact but is the uptake of free DNA from the environment by a competent bacterial cell. In some bacteria it is also mediated by a T4SS. The third mechanism depends on the presence of a bacteriophage, which can transfer genomic DNA from one host cell to another. Experimental evidence exists that all three modes occur in planktonic cultures and recent data have also been provided for the occurrence of all three ways in biofilms. Regulation of these HGT events and their consequences for the acting microbes and the biofilms they live in are discussed in this chapter. Additionally, we focus on modern techniques to visualize and to quantify HGT in planktonic and biofilm modes.
Environmental Deterioration and Human Health-Natural and anthropogenic determinants, 2014
Antibiotic-resistant pathogenic bacteria pose a high threat to human health, but the environmenta... more Antibiotic-resistant pathogenic bacteria pose a high threat to human health, but the environmental reservoirs of resistance genes are poorly understood. The origins of antibiotic resistance in the environment are relevant to human health because of the increasing importance of zoonotic diseases as well as the requirement for predicting emerging resistant pathogens. Only little is known about the antibiotic resistomes of the great majority of environmental bacteria, although there have been calls for a greater understanding of the environmental reservoirs of antibiotic resistance. The data on antibiotic resistance before the antibiotic era and in soil show how far away we are from a complete picture about the ecology of antibiotic resistance genes (ARGs). Most of the natural antibiotic producers reside in soil, but soil is a particularly challenging habitat due to its chemical and physical heterogeneity. The prevalence and diversity of ARGs in the environment led to hypotheses about the native roles of resistance genes in natural microbial communities.
Journal of Liquid Chromatography & Related Technologies, Jan 1, 2010
We present a video-densitometric quantification method for the triazine herbicides atraton, terbu... more We present a video-densitometric quantification method for the triazine herbicides atraton, terbumeton, simazine, atrazine, and terbutylazine. Triazine herbicides were separated on silica gel using methyl-t-butyl ether, cyclohexane (1+ 1, v/v) as mobile phase. The ...
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The antimicrobial coating efficiently inhibited the growth of the nosocomial pathogens Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium as demonstrated by the growth inhibition on agar surface and in biofilms of antibiotic resistant clinical E. faecalis, E. faecium, and S. aureus isolates. It also strongly reduced the growth of Legionella in a drinking water pipeline and of Escherichia coli in urine. We postulate a mode of action of the antimicrobial material, which is independent of the release of silver ions. Thus, the novel antimicrobial coating could represent an alternative to combat microbial growth avoiding the toxic side effects of high levels of silver ions on eukaryotic cells.
The antimicrobial coating efficiently inhibited the growth of the nosocomial pathogens Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium as demonstrated by the growth inhibition on agar surface and in biofilms of antibiotic resistant clinical E. faecalis, E. faecium, and S. aureus isolates. It also strongly reduced the growth of Legionella in a drinking water pipeline and of Escherichia coli in urine. We postulate a mode of action of the antimicrobial material, which is independent of the release of silver ions. Thus, the novel antimicrobial coating could represent an alternative to combat microbial growth avoiding the toxic side effects of high levels of silver ions on eukaryotic cells.