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Faecium
Kinds of Faecium Terms modified by Faecium Selected AbstractsEnhancement of Vancomycin Activity by Phenothiazines against Vancomycin-Resistant Enterococcus Faecium in vitroBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2010Mohammad Rahbar Minimum inhibitory concentrations (MIC) of the compounds were determined by agar dilution method, and synergy between phenothiazines and vancomycin was investigated using Checkerboard (microbroth dilution) technique. We found that all enterococci strains, regardless of their susceptibility to vancomycin, were inhibited by phenothiazines at concentrations varying from 8 to 256 ,g/ml, with thiethylperazine being the most potent inhibitory agent. Besides, all the phenothiazines showed partial synergy with vancomycin and could lessen MIC of vancomycin from 512 to 8 ,g/ml at their sub-inhibitory concentrations. The highest reduction in MIC was observed with chlorpromazine (32 times); however, thiethylperazine and promethazine stood next (24 times). Although resistance modification was observed at concentrations higher than those that phenothiazines reach in vivo, the potential offered by non-antibiotics justify further animal experiments as well as clinical trials to establish their clinical relevance. [source] Enterococcus faecalis with the gelatinase phenotype regulated by the fsr operon and with biofilm-forming capacity are common in the agricultural environmentENVIRONMENTAL MICROBIOLOGY, Issue 6 2009Lilia Macovei Summary The prevalence of gelatinase activity and biofilm formation among environmental enterococci was assessed. In total, 396 enterococcal isolates from swine and cattle faeces and house flies from a cattle farm were screened for gelatinase activity. The most prevalent phenotype on Todd,Hewitt agar with 1.5% skim milk was the weak protease (WP) (72.2% of isolates), followed by the strong protease (SP) 18.7%, and no protease (NP) (9.1%). The majority of WP isolates was represented by Enterococcus hirae (56.9%), followed by Enterococcus faecium (25.9%), Enterococcus casseliflavus (10.4%), Enterococcus gallinarum (5.2%) and Enterococcus saccharolyticus (1.7%). All WP isolates were negative for gelE (gelatinase) and sprE (serine protease) as well as the fsrABDC operon that regulates the two proteases, and only four isolates (7.0%) formed biofilms in vitro. All SP isolates were Enterococcus faecalis positive for the fsrABDC, gelE, sprE genes and the majority (91.2%) formed a biofilm. Diversity of NP isolates was relatively evenly distributed among E. hirae, E. faecium, E. casseliflavus, E. gallinarum, Enterococcus durans, E. saccharolyticus and Enterococcus mundtii. All NP isolates were negative for the fsr operon and only four E. hirae (11.1%) formed a biofilm. Of further interest was the loss of the gelatinase phenotype (18.9% of isolates) from SP isolates after 4 month storage at 4,8°C and several passages of subculture. Results of reverse transcription PCR analysis indicated that mRNA was produced for all the genes in the frs operon and sequencing of the gelE gene did not reveal any significant mutations. However, gelatinase was not detectable by Western blot analysis. Our study shows that E. faecalis with the complete fsr operon and the potential to form a biofilm are relatively common in the agricultural environment and may represent a source/reservoir of clinically relevant strains. In addition, many environmental enterococci, especially E. hirae, produce an unknown WP that can hydrolyse casein but does not contribute to biofilm formation. The stability of the gelatinase phenotype in E. faecalis and its regulation will require additional studies. [source] Structural organization of a complex family of palindromic repeats in EnterococciFEMS MICROBIOLOGY LETTERS, Issue 1 2009Eliana De Gregorio Abstract Enterococcus faecalis/faecium repeats (EFARs) are miniature insertion sequences spread in the genome of Enterococcus faecalis and Enterococcus faecium. Unit-length repeats measure 165,170 bp and contain two modules (B and T) capable of folding independently into stem-loop sequences, connected by a short, unstructured module J. The E. faecalis elements feature only one type of B, J and T modules. In contrast, the E. faecium elements result from the assembly of different types of B, J and T modules, and may vary in length because they carry multiple B modules. Most EFARs are located close (0,20 bp) to ORF stop codons, and are thus cotranscribed with upstream flanking genes. In both E. faecalis and E. faecium cells, EFAR transcripts accumulate in a strand-dependent fashion. Data suggest that T modules function as bidirectional transcriptional terminators, which provide a 3,-end to gene transcripts spanning B modules, while blocking antisense transcripts coming in from the opposite direction. [source] Increase of granzyme B-positive cells in ascitic fluid of patients with spontaneous bacterial peritonitisHEPATOLOGY RESEARCH, Issue 4 2008Alessandro Perrella Spontaneous bacterial peritonitis (SBP) occurs as a direct consequence of bacteria entering ascitic fluid (AF) from the intestinal lumen trough in several ways, including the hematogenous and mesenteric lymph nodes route. There are few studies on the cytokine profile of ascitic-derived mononuclear cells of patients with SBP, particularly on granzyme B (GZB). The aim of the present study was to verify whether patients with SBP have GZB-positive cells, whether they are increased in patients with aseptic ascites, and their trend after antibiotic treatment. We enrolled 36 consecutive patients (24 males and 12 females) with SBP on histologically-proven hepatitis C virus cirrhosis (group A) and 20 patients (11 males and nine females with ascites, but without evidences of SBP (group B). The diagnosis of SBP was made according to the following criteria: positive colture in AF or blood (at least two cultures) and neutrophils in AF (>250 mL polymorphonuclear leukocytes). For these patients we used ELISpot to assay GZB production on purified mononuclear cells in ascitesand peripheral blood, coupled with tumor necrosis factor-, tested using ELISA. A non-parametric statistical analysis was used to assess significant differences and correlations. We found positive culture in all of the patients with SBP (80% Escherichia coli; 20% Enterococcus faecium). Furthermore, the patients in group A had a higher number of GZB spot-forming colonies than the patients in group B (P < 0.001). GZB-positive cells were lower in the peripheral blood than those found in the AF of patients with SBP, while no differences were found between blood and AF in group B. Furthermore, after antibiotic treatment, GZB was reduced in the patients with SBP (P < 0.05). In conclusion, GZB may be an important mediator of the immune response towards bacteria in AF and could be used as a diagnostic tool. [source] The acute-phase response impairs host defence against Enterococcus faecium peritonitisIMMUNOLOGY, Issue 1pt2 2009Masja Leendertse Summary Enterococcus faecium is an emerging pathogen that causes infections in hospitalized patients with various co-morbid diseases. These underlying diseases are often associated with an acute-phase response that renders patients vulnerable to nosocomial infections. To study the influence of the acute-phase response induced by sterile tissue injury on host defence against E. faecium, mice were injected subcutaneously with either turpentine or casein 1 day before intraperitoneal infection with E. faecium. Control mice were subcutaneously injected with saline or sodium bicarbonate, respectively. Turpentine and casein induced an acute-phase response as reflected by increases in the plasma concentrations of interleukin-6, serum amyloid P and C3. A pre-existent acute-phase response in mice was associated with a strongly reduced capacity to clear E. faecium, resulting in prolonged bacteraemia for several days. The inflammatory response to E. faecium was impaired in mice with an acute-phase response, as shown by reduced capacity to mount a neutrophilic leucocytosis in peripheral blood and by decreased local cytokine concentrations. These data indicate that the acute-phase response impairs host defence against E. faecium, suggesting that this condition may contribute to the increased vulnerability of critically ill patients to enterococcal infections. [source] Technological characterization of the natural lactic acid bacteria of artisanal Turkish White Pickled cheeseINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2008ELIF DAGDEMIR The aim of this study was to characterize the lactic acid bacteria (LAB) isolated from White Pickled cheeses produced with traditional methods; and to improve the quality of cheesemaking with a selection of bacterial cultures from artisanal White cheeses. LAB were isolated and identified from 30 White Pickled cheese samples collected from various cities in Turkey. Also, the numbers of several microbial groups (total aerobic mesophilic bacteria, LAB, enterococci, coliforms, moulds and yeasts) of cheese samples were enumerated. Lactobacilli, lactococci and enterococci were the most abundant microbial groups. The numbers of Enterococcus and Lactobacillus isolates were higher than those of the other LAB. Enterococcus faecalis (24.43%), Enterococcus faecium (17.61%) and Lactobacillus fermentum (19.88%) isolates were the most frequently isolated species. Lactococcus strains showed the highest acidifying activity, followed by Enterococcus and Lactobacillus strains. Proteolytic activity of Enterococcus faecalis strains was higher than that of the other enterococci species, except Enterococcus avium strains. Within lactobacilli strains, the highest mean proteolytic activity was that of Lactobacillus bifermentans, Lactobacillus brevis and Lactobacillus casei strains. [source] ORIGINAL ARTICLE: Effect of Lactobacillus fermentum and Enterococcus faecium strains on internal milieu, antioxidant status and body weight of broiler chickensJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010M. Capcarova Summary The aim of the present study was to evaluate the functional efficiency of two probiotic strains Lactobacillus fermentum CCM 7158 and Enterococcus faecium M 74 given to the drinking water on internal milieu, antioxidant status and body weight of broiler chickens. The experiment was conducted on hybrid Hybro (n = 180). The feeding period lasted 42 days. Experimental chickens of E1 group received a probiotic preparation in drinking water with concentration of 1 × 109 colony forming units (CFU) of L. fermentum CCM 7158 in 1 g of nutrient medium and experimental chickens of E2 group concentration of 2 × 109 CFU of E. faecium M 74 in 1 g of nutrient medium. The control group of animals received water without any additives. Triglycerides content in serum mainly with L. fermentum strain against the control group was decreased. Calcium content in both experimental groups and significantly in E. faecium group was increased. Antioxidant status in both probiotic groups was significantly increased. The content of bilirubin in group with E. faecium M 74 was significantly increased. In conclusion, addition of a microbial feed additive (L. fermentum and E. faecium) increased serum calcium and iron level, decreased triglycerides content in blood and slightly increased body weight of broiler chickens. [source] Frequent occurrence of multidrug-resistant CC17 Enterococcus faecium among clinical isolates in SwedenJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2010H. Billström Abstract Aims:, To screen for the globally spread cluster of Enterococcus faecium, clonal complex 17 (CC17) and characterize the genetic profile of Swedish clinical Ent. faecium isolates. Methods:, A total of 203 consecutive isolates collected from 2004 to 2007 from patients with bacteraemia in Sweden. All isolates were genotyped using multiple-locus variable-number tandem repeat analysis (MLVA) and 20 isolates representing different MLVA types (MT) were chosen for multilocus sequence typing (MLST). Minimal inhibitory concentrations against clinically relevant antibiotics were determined with agar dilution. Presence of the virulence genes esp and hyl was investigated using PCR. Results:, A total of 65% (n = 109) of all isolates belonged to MT-1, and the second most common MLVA type was MT-159 (13%, n = 21). MLST analysis confirmed the presence of CC17 during the entire study period. The number of isolates resistant to gentamicin and vancomycin, as well as the presence of hyl, increased significantly during the investigation period. Conclusions:, The present study demonstrates that nosocomial infections caused by Ent. faecium CC17 are commonly occurring in Sweden. Significance and Impact of the Study:, This is the first report of CC17 Ent. faecium in Sweden. The increase of antibiotic resistance and virulence indicates that these strains are further adapting to the hospital environment. [source] Characterization of enterococci populations collected from a subsurface flow constructed wetlandJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2010A.K. Graves Abstract Aims:, The aim of this study was to identify and characterize the population of Enterococcus sp. in domestic wastewater as it flows through a constructed wetland. Methods and Results:, Four hundred and eighty-four Enterococcus isolates were collected from the inlet, various sites within and from the outlet of a plastic lined constructed wetland in College Station, TX. The wetland treated septic tank effluent that passed sequentially through two 1·89 m3 septic tanks and a 1·89 m3 pump tank allowing 48 l doses at a 24 l min,1 rate. The Enterococcus isolates were identified to species using the commercial Biolog system. The 484 Enterococcus isolates were comprised of ten different species, including Enterococcus faecalis (30·6%), Enterococcus pseudoavium (24·0%), Enterococcus casseliflavus (12·8%), Enterococcus faecium (11·2%), Enterococcus mundtii (7·9%), Enterococcus gallinarum (6·2%), Enterococcus dispar (3·7%), Enterococcus hirae (2·1%), Enterococcus durans and Enterococcus flavescens both 0·8%. Of the 88 isolates collected from the inlet, only 9·1% of the isolates were identified as Ent. faecalis and Ent. pseudoavium (36·4%) was identified as the predominant species. Whereas of the 74 isolates collected from the outlet, the predominant species were identified as Ent. faecalis (29·7%). Species identification varied among sites within the wetland, but often Ent. faecalis was the predominant species. Conclusions:, Our data suggest that while Ent. faecalis is the predominant species of Enterococcus found in domestic wastewater, the populations may shift during treatment as the wastewater flows through the constructed wetland. Significance and Impact of the Study:, We found that shifts in Enterococcus species composition occurred during domestic wastewater treatment. This has implications for the identification of faecal pollution based on the presence of specific bacterial types associated with domestic wastewater. [source] Application of microbial source tracking methods in a Gulf of Mexico field settingJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2009A. Korajkic Abstract Aims:, Microbial water quality and possible human sources of faecal pollution were assessed in a Florida estuary that serves shellfishing and recreational activities. Methods and Results:, Indicator organisms (IO), including faecal coliforms, Escherichia coli and enterococci, were quantified from marine and river waters, sediments and oysters. Florida recreational water standards were infrequently exceeded (6,10% of samples); however, shellfishing standards were more frequently exceeded (28%). IO concentrations in oysters and overlaying waters were significantly correlated, but oyster and sediment IO concentrations were uncorrelated. The human-associated esp gene of Enterococcus faecium was detected in marine and fresh waters at sites with suspected human sewage contamination. Lagrangian drifters, used to determine the pathways of bacterial transport and deposition, suggested that sediment deposition from the Ochlockonee River contributes to frequent detection of esp at a Gulf of Mexico beach. Conclusions:, These data indicate that human faecal pollution affects water quality in Wakulla County and that local topography and hydrology play a role in bacterial transport and deposition. Significance and Impact of the Study:, A combination of IO enumeration, microbial source tracking methods and regional hydrological study can reliably inform regulatory agencies of IO sources, improving risk assessment and pollution mitigation in impaired waters. [source] Prevalence, species distribution and antimicrobial resistance of enterococci isolated from dogs and cats in the United StatesJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2009C.R. Jackson Abstract Aims:, The contribution of dogs and cats as reservoirs of antimicrobial resistant enterococci remains largely undefined. This is increasingly important considering the possibility of transfer of bacteria from companion animals to the human host. In this study, dogs and cats from veterinary clinics were screened for the presence of enterococci. Methods and Results:, A total of 420 enterococci were isolated from nasal, teeth, rectal, belly and hindquarters sites of 155 dogs and 121 cats from three clinics in Athens, GA. Eighty per cent (124 out of 155) of the dogs and 60% (72 out of 121) of the cats were positive for enterococci. From the total number of dog samples (n = 275), 32% (n = 87) were from hindquarter, 31% (n = 86) were rectal, and 29% (n = 79) were from the belly area. The majority of isolates originated from rectal samples (53 out of 145; 37%) from cats. The predominant species identified was Enterococcus faecalis (105 out of 155; 68%) from dogs and E. hirae (63 out of 121; 52%) from cats. Significantly more E. faecalis were isolated from rectal samples than any other enterococcal species (P < 0·05) for both dogs and cats suggesting site specific colonization of enterococcal species. The highest levels of resistance were to ciprofloxacin in E. faecium (9 out of 10; 90%), chloramphenicol resistance in E. faecalis (17 out of 20; 85%) and gentamicin resistance in E. faecalis (19 out of 24; 79%) from dog samples and nitrofurantoin resistance in E. faecium (15 out of 19; 79%) from cats. Multi-drug resistance (MDR) (resistance ,2 antimicrobials) was observed to as few as two and as many as eight antimicrobials regardless of class. Conclusion:, This study demonstrated that dogs and cats are commonly colonized with antimicrobial resistant enterococci. Significance and Impact of the Study:, Dogs and cats may act as reservoirs of antimicrobial resistance genes that can be transferred from pets to people. [source] Preliminary characterization of lactic acid bacteria isolated from Zlatar cheeseJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2007K. Veljovic Abstract Aims:, Isolation, characterization and identification of lactic acid bacteria (LAB) from artisanal Zlatar cheese during the ripening process and selection of strains with good technological characteristics. Methods and Results:, Characterization of LAB was performed based on morphological, physiological and biochemical assays, as well as, by determining proteolytic activity and plasmid profile. rep-polymerase chain reaction (PCR) analysis and 16S rDNA sequencing were used for the identification of LAB. PCR analysis was performed with specific primers for detection of the gene encoding nisin production. Strains Lactobacillus paracasei subsp. paracasei, Lactobacillus plantarum, Lactobacillus brevis, Lactococcus lactis subsp. lactis, Enterococcus faecium and Enterococcus faecalis were the main groups present in the Zlatar cheese during ripening. Conclusions:, Temporal changes in the species were observed during the Zlatar cheese ripening. Mesophilic lactobacilli are predominant microflora in Zlatar cheese. Significance and Impact of the Study:, In this study we determined that Zlatar cheese up to 30 days old could be used as a source of strains for the preparation of potential starter cultures in the process of industrial cheese production. As the Serbian food market is adjusting to European Union regulations, the standardization of Zlatar cheese production by using starter culture(s) based on autochtonous well-characterized LAB will enable the industrial production of this popular cheese in the future. [source] Purification and characterization of two bacteriocins produced by lactic acid bacteria isolated from Mongolian airagJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2006B. Batdorj Abstract Aims:, The aim of this study was to isolate and identify bacteriocin-producing lactic acid bacteria (LAB) issued from Mongolian airag (traditional fermented mare's milk), and to purify and characterize bacteriocins produced by these LAB. Methods and Results:, Identification of the bacteria (Enterococcus durans) was carried out on the basis of its morphological, biochemical characteristics and carbohydrate fermentation profile and by API50CH kit and 16S rDNA analyses. The pH-neutral cell-free supernatant of this bacterium inhibited the growth of several Lactobacillus spp. and food-borne pathogens including Escherichia coli, Staphylococcus aureus and Listeria innocua. The antimicrobial agent (enterocin A5-11) was heat stable and was not sensitive to acid and alkaline conditions (pH 2,10), but was sensitive to several proteolytic enzymes. Its inhibitory activity was completely eliminated after treatment with proteinase K and , -chymotrypsin. The activity was however not completely inactivated by other proteases including trypsin and pepsin. Three-step purification procedure with high recovery yields was developed to separate two bacteriocins. The applied procedure allowed the recovery of 16% and 64% of enterocins A5-11A and A5-11B, respectively, present in the culture supernatant with purity higher than 99%. SDS-PAGE analyses revealed that enterocin A5-11 has a molecular mass of 5000 Da and mass spectrometry analyses demonstrates molecular masses of 5206 and 5218 Da for fractions A and B, respectively. Amino acid analyses of both enterocins indicated significant quantitative difference in their contents in threonine, alanine, isoleucine and leucine. Their N -termini were blocked hampering straightforward Edman degradation. Conclusions:, Bacteriocins A5-11A and B from Ent. durans belong to the class II of bacteriocins. Significance and Impact of the Study:, Judging from molecular masses, amino acid composition and spectrum of activities, bacteriocins A5-11A and B from Ent. durans show high degree of similarity with enterocins L50A and L50B isolated from Enterococcus faecium (Cintas et al. 1998, 2000) and with enterocin I produced by Ent. faecium 6T1a, a strain originally isolated from a Spanish-style green olive fermentation (Floriano et al. 1998). [source] Genetic characterization of vancomycin-resistant enterococci isolates from wild rabbitsJOURNAL OF BASIC MICROBIOLOGY, Issue 5 2009Nicholas Figueiredo Abstract The presence of van A-containing E. faecium isolates was demonstrated in three of 77 faecal samples (3.9%) of wild rabbits recovered in Portugal. Enterococcal strains with intrinsic vancomycin resistance (van C-1 or van C-2/3 gene) were found in five (6.5%) and three (3.9%) faecal samples, respectively. The mechanisms of resistance for other antibiotics were studied in these vancomycin-resistant isolates. All van A strains showed resistance for tetracycline [with the presence of tet (L) gene, associated or not with tet (M) gene] and for erythromycin [with the presence of the erm (B) gene]. Two isolates were resistant to ciprofloxacin and one to ampicillin. Two van C-1 strains and one van C-2/3 strain were tetracycline resistant [containing the tet (M) gene associated with tet (L) gene] and erythromycin resistant [with erm (B) gene]. Two van C-1 and two van C-2/3 strains were also ciprofloxacin resistant and one van C-1 strain was, additionally, resistant to quinupristin-dalfopristin. The two remaining isolates (van C-1, van C-2/3) did not show resistance for any additional antibiotic. The intestinal tract of wild rabbits could be a reservoir of van A-containing enterococci. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Isolation and identification of mixed linked , -glucan degrading bacteria in the intestine of broiler chickens and partial characterization of respective 1,3-1,4- , -glucanase activitiesJOURNAL OF BASIC MICROBIOLOGY, Issue 3 2006Lutz Beckmann Media with 1,3-1,4- , -glucans as selective markers were used for isolation of non-starch-polysaccharide (NSP) degrading bacteria from the intestinal tract of broiler chicken. Formerly unknown 1,3-1,4- , endoglucanase activities in various bacterial species were identified in this study. E. faecium , Streptococcus , Bacteroides and Clostridium strains seem to be responsible for degradation of mixed linked , -glucans in the small intestine and in the hind gut of chickens. Strict anaerobic bacteria (Bacteroides ovatus , B. uniformis , presumably B. capillosus and Clostridium perfringens ) as well as an unidentified bacterium with 98% 16S rDNA homology to an uncultered chicken cecum bacterium were isolated. Additionally, Streptococcus bovis with 1,3-1,4- , -endoglucanase activity was also detected. Different 1,3-1,4- , -endoglucanase activity profiles were observed in SDS/PAGE zymograms. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] HIGH PREVALENCE OF EXTENDED-SPECTRUM ,-LACTAMASES ESCHERICHIA COLI AND VANCOMYCIN-RESISTANT ENTEROCOCCI ISOLATES FROM CHICKEN PRODUCTS.JOURNAL OF FOOD SAFETY, Issue 1 2010A PROBLEM OF PUBLIC HEALTH ABSTRACT Twenty-nine chicken products were acquired from different supermarkets in Portugal during September to December 2007 and were analyzed for extended-spectrum ,-lactamases (ESBL) Escherichia coli and vancomycin-resistant enterococci (VRE). Cefotaxime-resistant E. coli isolates were recovered in 27 of 29 chicken samples representing 93% of the analyzed samples. The highest percentages of resistance (more than 50% of the isolates) were detected for ampicillin, nalidixic acid and tetracycline. VRE isolates were detected in 17 of 29 samples of chicken origin (59%) and were identified as Enterococcus durans (n = 15) and E. faecium (n = 2) with the highest percentages of resistance being detected for erythromycin, tetracycline, ampicillin and ciprofloxacin. Seven E. durans and the two E. faecium isolates recovered from chicken wings, gizzard and skin show gelatinase activity. The high rate of colonization of chicken products by these bacteria supports other studies suggesting that the food chain could be a source of ESBL and VRE colonization in humans representing a public health problem. PRACTICAL APPLICATIONS The data indicate that chicken products may be contaminated with a high prevalence of extended-spectrum ,-lactamases Escherichia coli and vancomycin-resistant enterococci (VRE). It is important to mention that the isolates present a diversity of phenotypes of antimicrobial resistance, and half of the VRE isolates show also gelatinase activity, indicating that these animals may be a reservoir of bacteria showing virulence and increased resistance to antimicrobial agents, raising special concerns about their transmission to humans through the food chain. [source] Removal of Cadmium and Lead from Aqueous Solution by,Enterococcus faecium,StrainsJOURNAL OF FOOD SCIENCE, Issue 1 2010A. Topcu ABSTRACT:, Foods may be contaminated with heavy metals, which, even in small quantities, possess detrimental effects on human health. The aim of the present study was to investigate the uptake of cadmium or lead from an aqueous medium frequently found in foods, by 2,Enterococcus faecium,strains (E. faecium,EF031 and,E. faecium,M74). Also, the effects of the bacterial viability, incubation (contact) time, and pH on the binding capacities and binding stability were assessed. The results showed that both of the strains efficiently removed cadmium and lead. While EF031 removed 77.3% to 98.1% of cadmium and 66.9% to 98.9% of lead, M74 removed 53.5% to 91% of cadmium and 42.9% to 93.1% of lead throughout a 48 h incubation period at pH 5. It was found that, at 1 h, EF031 and M74 strains removed cadmium and lead, which was more than 60% of total removed cadmium and lead throughout the whole incubation period of 48 h. It suggests that the uptake of cadmium and lead by EF031 and M74 strains is a rapid process. The binding of both heavy metals increased with increasing pH of an aqueous medium and was the highest at pH 5. Also, the complexes formed between both heavy metals and bacterial cells were found to be stable. These findings indicate that,E. faecium,strains used in the study are able to bind the 2 heavy metals and may be used in the production of fermented functional foods, which will be healthy via its detoxification properties. [source] Safety and Functional Aspects of Preselected Enterococci for Probiotic Use in Iberian Dry-Fermented SausagesJOURNAL OF FOOD SCIENCE, Issue 7 2009Santiago Ruiz-Moyano ABSTRACT:, The purpose of this study was to investigate enterococci for potential probiotic use in Iberian dry-fermented sausages. A total of 15 strains isolated from Iberian dry-fermented sausages, human feces, and pig feces were evaluated for their safety and functional characteristics including biogenic amine (BA) production, antibiotic susceptibility, hemolysis, virulence determinants, cell adhesion, and antimicrobial activity against foodborne pathogens. The strain,Enterococcus faecium,SE906 was able to establish itself on the intestinal epithelium, inhibiting such pathogenic bacteria as,Listeria monocytogenes in vitro. This strain was also considered safe to be used for its low aminogenic potential, and its antibiotic resistance pattern and virulence determinants, being identified as a potential probiotic meat starter culture suitable for manufacture of dry-fermented Iberian sausages. [source] Clonal groups of high-level gentamicin-resistant Enterococcus faecium isolated from municipal wastewater and clinical samples in Tehran, IranLETTERS IN APPLIED MICROBIOLOGY, Issue 2 2009M. Saifi Abstract Aims:, Clonality among high-level gentamicin-resistant Enterococcus faecium (HLGR-EF) isolates obtained from clinical and sewage treatment plants (STP) were investigated using PhePlate system (PhP), ribotyping and pulsed-field gel electrophoresis (PFGE). Methods and Results:, During 1 year study (September 2005,2006), a total of 106 HLGR-EF isolates were collected from clinical (n = 48) and STP (n = 58) samples in Tehran, Iran. Biochemical fingerprinting of these isolates using the PhP showed the presence of 21 PhP types (diversity index, Di = 0·97) among the clinical and 21 PhP types (Di = 0·91) among the STP isolates. Representative isolates of each PhP type (n = 42) were further characterized by the ribotyping method. Sixteen ribotypes were identified among the isolates with five types shared between the clinical and STP isolates. PFGE recognized 24 clonal types among these isolates with three pulsotypes shared between the clinical and STP isolates. Combination of the two techniques (PFGE and ribotyping) resulted in 24 (Di = 0·96) and 16 (Di = 0·93) types among the strains isolated from clinical and STP samples, respectively. Conclusions:, We concluded that the combination of PhP typing, ribotyping and PFGE could be extremely discriminatory when examining HLGR-EF isolates. Significance and Impact of the Study:, The emergence of highly diverse HLGR-EF population in Iran is of serious concern especially because of their multi-resistances. [source] Isolation and characterization of lactic acid bacteria from dochi (fermented black beans), a traditional fermented food in TaiwanLETTERS IN APPLIED MICROBIOLOGY, Issue 2 2006Y.-S. Chen Abstract Aims:, To isolate, characterize and identify lactic acid bacteria (LAB) in dochi (fermented black beans), a traditional fermented food in Taiwan. Methods and Results:, A total of 30 samples were collected from three different dochi producers and analysed after different periods of storage. Fifty-two cultures of LAB were isolated from dochi samples and the isolates were divided into classes by phenotype and then into groups by restriction fragment length polymorphism analysis and sequencing of 16S ribosomal DNA. Phenotypic and biochemical characteristics identified six different bacterial groups (A,F) and showed that the majority of the isolates were homofermentative LAB. Enterococcus faecium was the most abundant of the dochi -isolated LAB. All isolated LAB were able to grow in MRS broth containing 6% NaCl, but only Enterococcus, Pediococcus and Tetragenococcus species could grow in MRS broth containing 10% NaCl. Furthermore, antibacterial activities of isolates were determined, and four isolates showed inhibitory activities against the indicator strain Lactobacillus sakei JCM 1157T. Conclusions:, These results suggest that Ent. faecium is the main LAB present during the fermentation of dochi. Significance and Impact of the Study:, This is the first report describing the distribution and varieties of LAB that exist in the dochi fermentation process. [source] Identification and characterization of enterococci from bryndza cheeseLETTERS IN APPLIED MICROBIOLOGY, Issue 6 2006D. Jurkovi Abstract Aims:, To identify enterococci isolated from sheep milk cheese , bryndza, and to compare differences in the composition of enterococcal microflora affected by the season, and to evaluate the potential presence of vancomycin resistance and virulence determinants. Methods and Results:, Bacterial strains were isolated during analysis of bryndza cheese and identified on the genus and species level by phenotypic methods and with commercial biochemical sets. The identification of the species, Enterococcus faecium, Ent. durans and Ent. faecalis, was confirmed by PCR using species-specific primers for ddl genes. PCR was also used for assessment of presence of vanA and vanB genes and virulence determinants gelE, agg and cytolysin genes namely: cylLL, cylLS, cylM, cylB and cylA. Among 308 Enterococcus sp. strains, 177 isolates were proved to be Ent. faecium, 59 to be Ent. durans and 41 to be Ent. faecalis. Vancomycin resistance genes vanA and vanB were not detected. Agar plate testing confirmed their absence. Gene gelE, however, was found in 20 Ent. faecalis isolates, but only 13 of them showed gelatinase-positive phenotype. Seven isolates had five cytolysin genes, but none of the isolates exhibited a positive haemolytic phenotype. Four isolates possessed the agg gene. The prevalence of Ent. faecium species was highest in samples from the winter season harvest. Conclusions:,Ent. faecium is the dominant enterococcal species in bryndza cheese and the most prevalent in the winter season product. None of the Enterococcus sp. strains was proved to have vanA or vanB genes and the vancomycin resistance. Significance and Impact of the Study:, To our knowledge, this is the first report of enterococcal microflora in bryndza cheese and its evaluation for the presence of vanA and vanB genes as well as virulence determinants. [source] Screening of some plants from Northern Argentina for their antimicrobial activityLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2001Salvat Aims: Screening of antimicrobial activity in 25 plant species from Northern Argentina. Methods and Results: Inhibition of microbial growth was measured by a microplate assay with an oxidation,reduction indicator (Alamar Blue). Test organisms were: Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus and Enterococcus faecium. Weak inhibitory activities (MIC=0·5 mg dry matter ml,1) were found in methanolic extracts of Rivina humilis, Crateva tapia, Funastrum claucum and Schinopsis balansae. Stronger bacteriostatic power was detected in Vassobia breviflora (MIC=0·25 mg ml,1 against Staphylococcus aureus, and 0·5 mg ml,1 against Enterococcus faecium). This activity was purified five-fold by extraction with dichloromethane, and it was found equally effective against susceptible or antibiotic-resistant strains of Staph. aureus. In addition, the purified extract was synergistic with gentamicin, and it was bactericidal at 24 h, with a concentration of 0·25 mg ml,1. Conclusions: There is a significant antimicrobial activity in Vassobia breviflora. Significance and Impact of the Study: Further studies will be required to disclose the potential importance of these findings. [source] A six amino acid deletion, partially overlapping the VanSB G2 ATP-binding motif, leads to constitutive glycopeptide resistance in VanB-type Enterococcus faeciumMOLECULAR MICROBIOLOGY, Issue 3 2003Florence Depardieu Summary Enterococcus faecium clinical isolate BM4524, resistant to vancomycin and susceptible to teicoplanin, harboured a chromosomal vanB cluster, including the vanSB / vanRB two-component system regulatory genes. Enterococcus faecium strain BM4525, isolated two weeks later from the same patient, was resistant to high levels of both glycopeptides. The ddl gene of BM4525 had a 2 bp insertion leading to an impaired d -alanine: d -alanine ligase. Sequencing of the vanB operon in BM4525 also revealed an 18 bp deletion in the vanSB gene designated vanSB, . The resulting six amino acid deletion partially overlapped the G2 ATP-binding domain of the VanS B, histidine kinase leading to constitutive expression of the resistance genes. Sequence analysis indicated that the deletion occurred between two tandemly arranged heptanucleotide direct repeats, separated by 11 base-pairs. The VanS B , VanS B, and VanR B proteins were overproduced in Escherichia coli and purified. In vitro autophosphorylation of the VanS B and VanS B, histidine kinases and phosphotransfer to the VanR B response regulator did not differ significantly. However, VanS B, was deficient in VanR B phosphatase activity leading to accumulation of phosphorylated VanR B . Increased glycopeptide resistance in E. faecium BM4525 was therefore a result of the lack of production of d -alanyl- d -alanine ending pentapeptide and to constitutive synthesis of d -alanyl- d -lactate terminating peptidoglycan precursors, following loss of d -alanine: d -alanine ligase and of VanS B phosphatase activity respectively. We suggest that the heptanucleotide direct repeat in vanSB may favour the appearance of high level constitutively expressed vancomycin resistance through a ,slippage' type of genetic rearrangement in VanB-type strains. [source] Clinical isolates of Enterococcus faecium exhibit strain-specific collagen binding mediated by Acm, a new member of the MSCRAMM familyMOLECULAR MICROBIOLOGY, Issue 6 2003Sreedhar R. Nallapareddy Summary A collagen-binding adhesin of Enterococcus faecium, Acm, was identified. Acm shows 62% similarity to the Staphylococcus aureus collagen adhesin Cna over the entire protein and is more similar to Cna (60% and 75% similarity with Cna A and B domains respectively) than to the Enterococcus faecalis collagen-binding adhesin, Ace, which shares homology with Acm only in the A domain. Despite the detection of acm in 32 out of 32 E. faecium isolates, only 11 of these (all clinical isolates, including four vancomycin-resistant endocarditis isolates and seven other isolates) exhibited binding to collagen type I (CI). Although acm from three CI-binding vancomycin-resistant E. faecium clinical isolates showed 100% identity, analysis of acm genes and their promoter regions from six non-CI-binding strains identified deletions or mutations that introduced stop codons and/or IS elements within the gene or the promoter region in five out of six strains, suggesting that the presence of an intact functional acm gene is necessary for binding of E. faecium strains to CI. Recombinant Acm A domain showed specific and concentration-dependent binding to collagen, and this protein competed with E. faecium binding to immobilized CI. Consistent with the adherence phenotype and sequence data, probing with Acm-specific IgGs purified from anti-recombinant Acm A polyclonal rabbit serum confirmed the surface expression of Acm in three out of three collagen-binding clinical isolates of E. faecium tested, but in none of the strains with a non-functional pseudo acm gene. Introduction of a functional acm gene into two non-CI-binding natural acm mutant strains conferred a CI-binding phenotype, further confirming that native Acm is sufficient for the binding of E. faecium to CI. These results demonstrate that acm, which encodes a potential virulence factor, is functional only in certain infection-derived clinical isolates of E. faecium, and suggest that Acm is the primary adhesin responsible for the ability of E. faecium to bind collagen. [source] Axe,Txe, a broad-spectrum proteic toxin,antitoxin system specified by a multidrug-resistant, clinical isolate of Enterococcus faeciumMOLECULAR MICROBIOLOGY, Issue 5 2003Ruth Grady Summary Enterococcal species of bacteria are now acknowledged as leading causes of bacteraemia and other serious nosocomial infections. However, surprisingly little is known about the molecular mechanisms that promote the segregational stability of antibiotic resistance and other plasmids in these bacteria. Plasmid pRUM (24 873 bp) is a multidrug resistance plasmid identified in a clinical isolate of Enterococcus faecium. A novel proteic-based toxin,antitoxin cassette identified on pRUM was demonstrated to be a functional segregational stability module in both its native host and evolutionarily diverse bacterial species. Induced expression of the toxin protein (Txe) of this system resulted in growth inhibition in Escherichia coli. The toxic effect of Txe was alleviated by co-expression of the antitoxin protein, Axe. Homologues of the axe and txe genes are present in the genomes of a diversity of Eubacteria. These homologues (yefM,yoeB) present in the E. coli chromosome function as a toxin,antitoxin mechanism, although the Axe and YefM antitoxin components demonstrate specificity for their cognate toxin proteins in vivo. Axe,Txe is one of the first functional proteic toxin,antitoxin systems to be accurately described for Gram-positive bacteria. [source] Virulence, phenotype and genotype characteristics of endodontic Enterococcus spp.MOLECULAR ORAL MICROBIOLOGY, Issue 1 2005C. M. Sedgley Background/aims:, Enterococci have been implicated in persistent root canal infections but their role in the infection process remains unclear. This study investigated the virulence, phenotype and genotype of 33 endodontic enterococcal isolates. Methods:, Phenotypic tests were conducted for antibiotic resistance, clumping response to pheromone, and production of gelatinase, hemolysin and bacteriocin. Genotype analysis involved polymerase chain reaction amplification of virulence determinants encoding aggregation substances asa and asa373, cytolysin activator cylA, gelatinase gelE, gelatinase-negative phenotype ef1841/fsrC, adherence factors esp and ace, and endocarditis antigen efaA. Physical DNA characterization involved pulsed-field gel electrophoresis of genomic DNA, and plasmid analysis. Results:, Potential virulence traits expressed included production of gelatinase by Enterococcus faecalis (n = 23), and response to pheromones in E. faecalis culture filtrate (n = 16). Fourteen strains produced bacteriocin. Five strains were resistant to tetracycline and one to gentamicin, whereas all were susceptible to ampicillin, benzylpenicillin, chloramphenicol, erythromycin, fusidic acid, kanamycin, rifampin, streptomycin and vancomycin. Polymerase chain reaction products encoding efaA, ace, and asa were detected in all isolates; esp was detected in 20 isolates, cylA in six isolates, but asa373 was never detected. The gelatinase gene (gelE) was detected in all isolates of E. faecalis (n = 31) but not in Enterococcus faecium (n = 2); a 23.9 kb deletion sequence corresponding to the gelatinase-negative phenotype was detected in six of the eight E. faecalis isolates that did not produce gelatinase. Pulsed-field gel electrophoresis and plasmid analyses revealed genetic polymorphism with clonal types evident. Plasmid DNA was detected in 25 strains, with up to four plasmids per strain and a similar (5.1 kb) plasmid occurring in 16 isolates. Conclusions:, Phenotypic and genotypic evidence of potential virulence factors were identified in endodontic Enterococcus spp., specifically production of gelatinase and response to pheromones. [source] Isolation of vancomycin-resistant enterococci from pigs in JapanANIMAL SCIENCE JOURNAL, Issue 6 2003Yuri SAKAI ABSTRACT Forty vancomycin-resistant enterococci (VRE) were isolated from feces of pigs in one pig farm. Two strains were further elucidated and these were biochemically identified as Enterococcus faecium possessing the vanB gene. These isolates showed high resistance to vancomycin and nine other antibiotics. This is the first report of VRE contamination in pigs in Japan. [source] Probiotic applications for rainbow trout (Oncorhynchus mykiss Walbaum) II.AQUACULTURE NUTRITION, Issue 5 2010Effects on growth performance, feed utilization, intestinal microbiota, related health criteria postantibiotic treatment Abstract The effect of dietary probiotics (Bacillus subtilis, Bacillus licheniformis and Enterococcus faecium) was assessed on rainbow trout (Oncorhynchus mykiss Walbaum) previously treated with oxolinic acid. After feeding on supplemented diets for 10 weeks growth performance, feed utilization, gastrointestinal colonization and health status were assessed. B. subtilis + B. licheniformis fed fish displayed a significant improvement of feed conversation ration (FCR), specific growth rate (SGR) and protein efficiency ratio (PER). High levels of probiotic species were observed in the posterior gastrointestinal tract as transient digesta associated populations and potentially resident mucosal populations. Levels of Bacillus spp. reached log 3.74 CFU g,1 on the mucosal epithelium and log 7.41 CFU g,1 in the digesta of fish fed diets supplemented with B. subtilis and B. licheniformis. Enterococci levels reached log 2.84 CFU g,1 on the mucosa and log 7.78 CFU g,1 in the digesta of fish fed E. faecium supplemented diets. Feeding trout the Bacillus probionts alone or synergistically with E. faecium resulted in elevated leucocyte levels. The results of the current study demonstrate a potential role of probiotics for stabilizing/reinforcing the gastrointestinal microbiota after antibiotic treatment. This could reinvigorate the intestinal defensive barrier mechanism and provide protection against secondary potential pathogens. [source] Probiotic applications for rainbow trout (Oncorhynchus mykiss Walbaum) I. Effects on growth performance, feed utilization, intestinal microbiota and related health criteriaAQUACULTURE NUTRITION, Issue 5 2010D.L. MERRIFIELD Abstract The effect of dietary probiotics (Bacillus subtilis, Bacillus licheniformis and Enterococcus faecium) used singularly and synergistically on the growth performance, intestinal microbiota and health status of rainbow trout (Oncorhynchus mykiss Walbaum) were assessed after 10 weeks feeding on supplemented diets. No significant improvements of weight gain or specific growth rate were observed in the probiotic fed groups. However, a significant improvement of feed conversion ratio was observed in the group fed E. faecium. High levels of probiotic species were observed in the posterior gastrointestinal tract as transient digesta-associated populations and potentially resident mucosal populations. Bacillus subtilis and B. licheniformis levels accounted for 36% of the total culturable microbial population adhered to the mucosa and 62% in the digesta. E. faecium levels accounted for 45% of the mucosal population and 89% of the population in the digesta. An increase of serum lysozyme activity was observed in the fish fed diets containing the Bacillus probionts and elevated leukocyte levels were observed in fish fed diets containing Bacillus + E. faecium synergistically. The results of the current study demonstrate potential for B. subtilis, B. licheniformis and E. faecium to improve feed utilization, modulate intestinal microbiota and the health status of rainbow trout. [source] Haematologic and immunologic parameters of bullfrogs, Lithobates catesbeianus, fed probioticsAQUACULTURE RESEARCH, Issue 7 2010Danielle de Carla Dias Abstract The effects of two probiotics (P1,Lactobacillus acidophilus, Bifidobacterium bifidum and Enterococcus faecium and P2,Bacillus subtilis) supplemented to commercial feed (40% crude protein) on the haematological and immunological parameters of the bullfrog Lithobates catesbeianus were studied. Two doses of each probiotic (5 and 10 g kg,1 of food) were added to the diets and fed to frogs, totalling five treatments over 112 days. Haematological analyses consisted of total and differential leucocyte counts, erythrocyte and thrombocyte counts, haematocrit, haemoglobin levels and RBC indices (mean corpuscular volume, mean corpuscular haemoglobin , and mean corpuscular haemoglobin concentration) and the immunological parameters included phagocytic capacity and phagocytic index of peritoneal phagocytes. The results showed that the probiotics did not significantly influence any of the haematological parameters measured. However, immunological assays showed that the probiotics had an immunostimulating effect. The greatest effects were seen with probiotic P1 fed at a dose of 10 g kg,1 of diet and probiotic P2 fed at 5 g kg,1 of diet. [source] | |||||||||||||||||||