scholarly journals Isolation and Characterization of Bacteria Resistant to Metallic Copper Surfaces

2010 ◽  
Vol 76 (5) ◽  
pp. 1341-1348 ◽  
Author(s):  
Christophe Esp�rito Santo ◽  
Paula Vasconcelos Morais ◽  
Gregor Grass

ABSTRACT Metallic copper alloys have recently attracted attention as a new antimicrobial weapon for areas where surface hygiene is paramount. Currently it is not understood on a molecular level how metallic copper kills microbes, but previous studies have demonstrated that a wide variety of bacteria, including Escherichia coli, Staphylococcus aureus, and Clostridium difficile, are inactivated within minutes or a few hours of exposure. In this study, we show that bacteria isolated from copper alloy coins comprise strains that are especially resistant against the toxic properties exerted by dry metallic copper surfaces. The most resistant of 294 isolates were Gram-positive staphylococci and micrococci, Kocuria palustris, and Brachybacterium conglomeratum but also included the proteobacterial species Sphingomonas panni and Pseudomonas oleovorans. Cells of some of these bacterial strains survived on copper surfaces for 48 h or more. Remarkably, when these dry-surface-resistant strains were exposed to moist copper surfaces, resistance levels were close to those of control strains and MICs for copper ions were at or below control strain levels. This suggests that mechanisms conferring resistance against dry metallic copper surfaces in these newly isolated bacterial strains are different from well-characterized copper ion detoxification systems. Furthermore, staphylococci on coins did not exhibit increased levels of resistance to antibiotics, arguing against coselection with copper surface resistance traits.

2007 ◽  
Vol 74 (4) ◽  
pp. 977-986 ◽  
Author(s):  
Christophe Espírito Santo ◽  
Nadine Taudte ◽  
Dietrich H. Nies ◽  
Gregor Grass

ABSTRACT Bacterial contamination of touch surfaces poses a serious threat for public health. The use of bactericidal surface materials, such as copper and its alloys, might constitute a way to aid the use of antibiotics and disinfectants, thus minimizing the risk of emergence and spread of multiresistant germs. The survival of Escherichia coli on metallic copper surfaces has been studied previously; however, the mechanisms underlying bacterial inactivation on copper surfaces have not been elucidated. Data presented in this study suggest that bacteria are killed rapidly on dry copper surfaces. Several factors, such as copper ion toxicity, copper chelators, cold, osmotic stress, and reactive oxygen species, but not anaerobiosis, influenced killing rates. Strains deleted in copper detoxification systems were slightly more sensitive than was the wild type. Preadaptation to copper enhanced survival rates upon copper surface exposure. This study constitutes a first step toward understanding the reasons for metallic copper surface-mediated killing of bacteria.


2011 ◽  
Vol 183-185 ◽  
pp. 773-777 ◽  
Author(s):  
Jun Bo Pan ◽  
Min Zhao ◽  
Lei Lu ◽  
Mei Hui Du ◽  
Guo Fu Li ◽  
...  

Bacterial strains exhibiting laccase activity were isolated from the forest soil. A strain LC02 with syringaldazine oxidation ability was obtained using enrichment medium supplemented with copper ions. The isolated strain was identified as Bacillus amyloliquefaciens using physiological and biochemical tests as well as 16S rDNA sequence analysis. The characterization of spore laccase activity was investigated. The result showed that the optimum pH and temperature of the enzyme was 6.6 and 70°C, respectively. A great thermostability was observed for the spore laccase at 70°C. Laccase activity was strongly inhibited by 0.1 mmol/L NaN3, dithiothreitol and cysteine.


2010 ◽  
Vol 77 (2) ◽  
pp. 416-426 ◽  
Author(s):  
Davide Quaranta ◽  
Travis Krans ◽  
Christophe Espírito Santo ◽  
Christian G. Elowsky ◽  
Dylan W. Domaille ◽  
...  

ABSTRACTSurfaces made of copper or its alloys have strong antimicrobial properties against a wide variety of microorganisms. However, the molecular mode of action responsible for the antimicrobial efficacy of metallic copper is not known. Here, we show that dry copper surfaces inactivateCandida albicansandSaccharomyces cerevisiaewithin minutes in a process called contact-mediated killing. Cellular copper ion homeostasis systems influenced the kinetics of contact-mediated killing in both organisms. Deregulated copper ion uptake through a hyperactiveS. cerevisiaeCtr1p (ScCtr1p) copper uptake transporter inSaccharomycesresulted in faster inactivation of mutant cells than of wild-type cells. Similarly, lack of theC. albicansCrp1p (CaCrp1p) copper-efflux P-type ATPase or the metallothionein CaCup1p caused more-rapid killing ofCandidamutant cells than of wild-type cells.CandidaandSaccharomycestook up large quantities of copper ions as soon as they were in contact with copper surfaces, as indicated by inductively coupled plasma mass spectroscopy (ICP-MS) analysis and by the intracellular copper ion-reporting dye coppersensor-1. Exposure to metallic copper did not cause lethality through genotoxicity, deleterious action on a cell's genetic material, as indicated by a mutation assay withSaccharomyces. Instead, toxicity mediated by metallic copper surfaces targeted membranes in both yeast species. With the use of Live/Dead staining, onset of rapid and extensive cytoplasmic membrane damage was observed in cells from copper surfaces. Fluorescence microscopy using the indicator dye DiSBaC2(3) indicated that cell membranes were depolarized. Also, during contact-mediated killing, vacuoles first became enlarged and then disappeared from the cells. Lastly, in metallic copper-stressed yeasts, oxidative stress in the cytoplasm and in mitochondria was elevated.


2002 ◽  
Vol 68 (9) ◽  
pp. 4390-4398 ◽  
Author(s):  
S. A. F. T. van Hijum ◽  
G. H. van Geel-Schutten ◽  
H. Rahaoui ◽  
M. J. E. C. van der Maarel ◽  
L. Dijkhuizen

ABSTRACT Fructosyltransferase (FTF) enzymes produce fructose polymers (fructans) from sucrose. Here, we report the isolation and characterization of an FTF-encoding gene from Lactobacillus reuteri strain 121. A C-terminally truncated version of the ftf gene was successfully expressed in Escherichia coli. When incubated with sucrose, the purified recombinant FTF enzyme produced large amounts of fructo-oligosaccharides (FOS) with β-(2→1)-linked fructosyl units, plus a high-molecular-weight fructan polymer (>107) with β-(2→1) linkages (an inulin). FOS, but not inulin, was found in supernatants of L. reuteri strain 121 cultures grown on medium containing sucrose. Bacterial inulin production has been reported for only Streptococcus mutans strains. FOS production has been reported for a few bacterial strains. This paper reports the first-time isolation and molecular characterization of (i) a Lactobacillus ftf gene, (ii) an inulosucrase associated with a generally regarded as safe bacterium, (iii) an FTF enzyme synthesizing both a high molecular weight inulin and FOS, and (iv) an FTF protein containing a cell wall-anchoring LPXTG motif. The biological relevance and potential health benefits of an inulosucrase associated with an L. reuteri strain remain to be established.


2013 ◽  
Vol 33 (2) ◽  
pp. 295-303 ◽  
Author(s):  
Cintia Anabela Mazzucotelli ◽  
Alejandra Graciela Ponce ◽  
Catalina Elena Kotlar ◽  
María del Rosario Moreira

Nutrients ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1684 ◽  
Author(s):  
Larissa Celiberto ◽  
Roseli Pinto ◽  
Elizeu Rossi ◽  
Bruce Vallance ◽  
Daniela Cavallini

Modulation of the gut microbiota through the use of probiotics has been widely used to treat or prevent several intestinal diseases. However, inconsistent results have compromised the efficacy of this approach, especially in severe conditions such as inflammatory bowel disease (IBD). The purpose of our study was to develop a personalized probiotic strategy and assess its efficacy in a murine model of intestinal inflammation. Commensal bacterial strains were isolated from the feces of healthy mice and then administered back to the host as a personalized treatment in dextran sodium sulfate (DSS)-induced colitis. Colonic tissues were collected for histological analysis and to investigate inflammatory markers such as Il-1β, Il-6, TGF-β, and Il-10, and the enzyme myeloperoxidase as a neutrophil marker. The group that received the personalized probiotic showed reduced susceptibility to DSS-colitis as compared to a commercial probiotic. This protection was characterized by a lower disease activity index and reduced histopathological damage in the colon. Moreover, the personalized probiotic was more effective in modulating the host immune response, leading to decreased Il-1β and Il-6 and increased TGF-β and Il-10 expression. In conclusion, our study suggests that personalized probiotics may possess an advantage over commercial probiotics in treating dysbiotic-related conditions, possibly because they are derived directly from the host’s own microbiota.


2018 ◽  
Vol 6 (2) ◽  
pp. 500-508
Author(s):  
Julie Ann A. Arcales ◽  
Garner Algo L.Alolod

Isolation and characterization of bacteria in food products are important to determine and distinguish the beneficial or harmful effects of microbiota in certain samples. Lactic acid bacteria in food products had long been associated to good factors as food preservatives and with added fermentation metabolites. This study isolated and characterized lactic acid bacteria from burong bangus. The culture and purification process of bacteria isolation resulted to 4 strains of lactic acid bacteria namely Enterococcus faecalis, Tetragenococcus muriaticus, Lactobacillus delbrueckii subp. delbrueckii and Carnobacterium divergens. High enzymatic activity were observed with E. faecalis particularly on lipase and protease assay. While C. divergens have no enzymatic activity against lipase, protease, amylase and cellulase. The antimicrobial property of L. delbrueckii is only susceptible to amoxicillin unlike the other three bacteria isolates. No antagonistic activity were observed with the four bacterial strains against Bacillus subtilis, Staphylococcus aureus and Escherichia coli. The result of this study showed promising benefits to the industry especially in developing countries like the Philippines because population are not yet so aware of this organisms and the benefits that can be derived through their consumption.


Antibiotics ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 506
Author(s):  
Paula Maria Moreira Martins ◽  
Ting Gong ◽  
Alessandra A. de Souza ◽  
Thomas K. Wood

Due to their reduced metabolism, persister cells can survive most antimicrobial treatments, which usually rely on corrupting active biochemical pathways. Therefore, molecules that kill bacterial persisters should function in a metabolism-independent manner. Some anti-persister compounds have been found previously, such as the DNA-crosslinkers mitomycin C and cisplatin, but more effective and lower cost alternatives are needed. Copper alloys have been used since ancient times due to their antimicrobial properties, and they are still used in agriculture to control plant bacterial diseases. By stopping transcription with rifampicin and by treating with ampicillin to remove non-persister cells, we created a population that consists solely of Escherichia coli persister cells. Using this population of persister cells, we demonstrate that cupric compounds kill E. coli persister cells. Hence, copper ions may be used in controlling the spread of important bacterial strains that withstand treatment with conventional antimicrobials by forming persister cells.


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