Proteomic characterization of vanA-containing Enterococcus recovered from Seagulls at the Berlengas Natural Reserve, W Portugal (original) (raw)
Related papers
Letters in Applied Microbiology, 2010
Aims: To analyse the occurrence of faecal carriage of vancomycin-resistant enterococci (VRE) in Buteo buteo and to study the associated resistance and virulence genes.Methods and Results: The presence of VRE was investigated in 33 faecal samples of B. buteo. Samples were seeded in Slanetz–Bartley agar plates supplemented with vancomycin for VRE recovery. Genes encoding antimicrobial resistance and virulence were studied by polymerase chain reaction. Vancomycin-resistant Enterococcus faecium isolates were characterized by multilocus sequence typing. VRE with an acquired mechanism of resistance (vanA genotype) were detected in 9% of samples analysed (Ent. faecium and Enterococcus durans). In addition, 27% of samples contained VRE with an intrinsic mechanism of resistance (Enterococcus gallinarum, vanC1). All vanA-containing isolates showed resistance to tetracycline and erythromycin and harboured the tet(M) and/or tet(L) genes, in addition to the ermB gene. The vat(E) and/or vat(D), cat(A) and aph(3′)-IIIa genes were identified in quinupristin–dalfopristin-, chloramphenicol-, and kanamycin-resistant vanA-containing strains, respectively. The sequence types ST273 and ST5 were identified in two vanA-positive Ent. faecium isolates, and the presence of hyl, gelE, cylA, cylL and cylM virulence genes and gelatinase activity were identified in Ent. faecium ST5 strain.Conclusions: The intestinal tract of B. buteo could be a reservoir of vanA-positive enterococci.Significance and Impact of the Study: First study focused to define the occurrence of vanA-containing Enterococcus strains in B. buteo.
2021
With Enterococcus species in the leading cause of nosocomial infections and resistance to an array of antibiotics, this study focused to determine the frequency and distribution of vancomycin-resistant Enterococci, the presence of virulence genes and to determine the relative nucleotide sequence relatedness among isolates using 16S rRNA sequence. A random sampling of 120 fecal samples of cattle, poultry, and piggery, and human clinical isolates was analyzed. Standard bacteriological methods were employed in the isolation and characterization of isolates and the disk diffusion method was used in determining their antibiotic resistance profiles. Results showed Enterococcus species in cattle at 100%, followed by clinical isolates at 80%. Vancomycin resistance was observed at high rates in Enterococcus species from human clinical isolates and cattle isolates at 90% and 80% respectively. Multiple antibiotic-resistant isolates yielded twelve resistance profiles and 16S rDNA sequences identified E. faecalis, E. durans, E. mundtii, and Enterococcus sp. Isolates from cattle samples were the most probable source of clinical isolates at 78% homology of conserved regions with the clinical isolates. Virulence determinant genes Asa1 was recorded at66.6%, Cyl at 16.6% and GelE at 8.3% among the isolates. This study established farm animals as possible reservoirs of VRE isolates to man. Hence, healthy and professional practices among animal farmers with antibiotic usage, as well as hygienic and preventive measures among hospital workers are here recommended.
Diagnostic Microbiology and Infectious Disease, 2001
Enterococcus species isolated from poultry sources were characterized for their resistance to antibiotics, plasmid content, presence of van genes and their diversity by randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). The results showed that all isolates were multi-resistance to the antibiotics tested. Ampicillin (15/70) followed by chloramphenicol (37/70) were the most active antibiotics tested against the Enterococcus spp. isolates, while the overall resistant rates against the other antibiotics were between 64.3% to 100%. All vancomycin-resistant E. faecalis, E. durans, E. hirae and E. faecium isolates tested by the disk diffusion assay were positive in PCR detection for presence of vanA gene. All E. casseliflavus isolates were positive for vanC2/C3 gene. However, none of the Enterococcus spp. isolates were positive for vanB and vanC1 genes. Plasmids ranging in sizes between 1.1 to ca. 35.8 MDa were detected in 38/70 of the Enterococcus isolates. When the genetic relationship among all isolates of the individual species were tested by RAPD-PCR, genetic differences detected suggested a high genetic polymorphisms of isolates in each individual species. Our results indicates that further epidemiological studies are necessary to elucidate the role of food animals as reservoir of VRE and the public health significance of infections caused by Enterococcus spp.
Although normally regarded harmless commensals, enterococci may cause a range of different infections in humans, including urinary tract infections, sepsis, and endocarditis. The acquisition of vancomycin resistance by enterococci (VRE) has seriously affected the treatment and infection control of these organisms. VRE are frequently resistant to all antibiotics that are effective treatment for vancomycin-susceptible enterococci, which leaves clinicians treating VRE infections with limited therapeutic options. With VRE emerging as a global threat to public health, we aimed to isolate, identify enterococci species from tilapia and their resistance to van-mediated glycopeptide (vanA and vanC) as well as the presence of enterococcal surface protein (esp) using conventional and molecular methods. The cultural, biochemical (Vitek 2 system) and polymerase chain reaction results revealed eight Enterococcus isolates from the 80 fish samples (10%) to be further identified as E. faecalis (6/8, 75%) and E gallinarum (2/8, 25%). Intraperitoneal injection of healthy Nile tilapia with the eight Enterococcus isolates caused significant morbidity (70%) within 3 days and 100% mortality at 6 days post-injection with general signs of septicemia. All of the eight Enterococcus isolates were found to be resistant to tetracycline. The 6/6 E. faecalis isolates were susceptible for penicillin, nitrofurantoin, gentamicin, and streptomycin. On the other hand 5/6 were susceptible for ampicillin, vancomycin, chloramphenicol, and ciprofloxacin. The two isolates of E. gallinarum were sensitive to rifampicin and ciprofloxacin and resistant to vancomycin, chloramphenicol, and erythromycin. Molecular characterization proved that they all presented the prototypic vanC element. On the whole, one of the two vancomycin resistance gene was present in 3/8 of the enterococci isolates, while the esp virulence gene was present in 1/8 of the enterococci isolates. The results in this study emphasize the potential role that aquatic environments are correlated to proximity to anthropogenic activities in determining the antimicrobial resistance patterns of Enterococcus spp. recovered from fish in the river Nile in Giza, Elmounib, Egypt as a continuation of our larger study on the reservoirs of antibiotic resistance in the environment.
Journal of clinical microbiology, 1993
DNA probes specific for genes encoding rRNA and the glycopeptide resistance gene vanA were used to investigate a cluster of vancomycin-resistant (MICs, > 512 mg/liter) Enterococcus faecalis and Enterococcus faecium isolated from separate patients in a renal unit in a London hospital. When digested with BamHI, 12 of 13 vancomycin-resistant E. faecalis isolates exhibited a common restriction fragment length polymorphism pattern of rRNA genes (ribotype). A vanA probe hybridized with chromosomal DNA in these 12 isolates. The other isolate of vancomycin-resistant E. faecalis had a different ribotype and the vanA gene was located on plasmid DNA. These data suggest that cross-infection with a single strain of vancomycin-resistant E. faecalis occurred in most instances. In contrast, 23 vancomycin-resistant E. faecium isolates showed greater heterogeneity, comprising 8 ribotypes, suggesting that multiple strains were present in the unit. Twenty-one of these 23 isolates harbored a 24-MDa p...
Revista do Instituto de Medicina Tropical de São Paulo, 2008
Little is known about vancomycin-resistant enterococci in China. Thirteen pulsed-field gel electrophoresisconfirmed heterogeneous VanA-type vancomycin-resistant Enterococcus faecium (VRE) isolates were obtained from five Chinese hospitals from 2001 to 2005. The isolates were typed by multilocus sequence typing into nine different sequence types (STs), including five new STs (ST18, ST25, ST78, ST203, ST320, ST321, ST322, ST323, and ST335). Vancomycin resistance in each isolate was encoded on conjugative plasmids; two of the plasmids, pZB18 (67 kbp) and pZB22 (200 kbp), were highly conjugative and were able to transfer at high frequencies of around 10 ؊4 and 10 ؊7 per donor cell in broth mating, respectively. None of the plasmids identified in these isolates carried traA, which is usually conserved in the pMG1-like highly conjugative plasmid for E. faecium, implying that pZB18 and pZB22 were novel types of a highly conjugative plasmid in enterococci. Thirteen Tn1546-like elements encoding VanA-type VRE on the conjugative plasmids were classified into six types (types I to VI), and most of them contained both IS1216V and IS1542 insertions. The isolates carrying the type II element were predominant. The six type elements were different from that of a VanA-type Enterococcus faecalis strain isolated from Chinese chicken meat. The results suggested that the disseminations of VRE in these areas were by Tn1546-like elements being acquired by the conjugative plasmids and transferred among E. faecium strains.
[Molecular analysis of vancomycin-resistant enterococci isolated from clinical samples]
Mikrobiyoloji Bulteni, 2006
Geographic spread of vancomycin-resistant enterococci (VRE) clones in cities, countries, or even continents has been identified by molecular techniques. This study aimed at characterizing virulent genes and determining genetic relatedness of 45 VRE isolates from Trinidad and Tobago using molecular tools, including polymerase chain reaction, pulsed-field gel electrophoresis (PFGE), and Random Amplification Polymorphic DNA (RAPD). The majority (84%) of the isolates were Enterococcus faecium possessing vanA gene while the rest (16%) were Enterococcus faecalis possessing vanB. The esp gene was found in all 45 VRE isolates while hyl genes were found only in E. faecium species. The E. faecium species expressed five distinct PFGE patterns. The predominant clones with similar or common patterns belonged to clones one and three, and each had 11 (29%) of the VRE isolates. Plasmid content was identified in representative isolates from each clonal group. By contrast, the E. faecalis species had one PFGE pattern suggesting the presence of an occult and limited clonal spread. The emergence of VRE in the country seems to be related to intra/interhospital dissemination of an epidemic clone carrying the vanA element. Therefore, infection control measures will be warranted to prevent any potential outbreak and spread of VRE in the country.
Journal of Microbiology and Infectious Diseases, 2013
Objective: Enterococci are important nosocomial agents and due to their potential antimicrobial resistance they have a significant role in the dissemination of resistance genes. Currently, these species are described as healthcare concern. The aim of this study was to determine vanA and vanB genes in vancomycin resistant enterococci (VRE) strains isolated from the various clinical samples in the hospitals in Iran. Methods: Susceptibility of 235 strains to vancomycin was screened as minimum inhibitory concentration (MIC) by Etest. The genes encoding modifying vancomycin precursor's dipeptide termini named as vanA and vanB genes were targeted by Taq Man real time PCR assay in vancomycin resistant and vancomycin intermediate resistant Enterococcus faecalis and Enterococcus faecium strains. Results: A total of 235 enterococci were isolated from the clinical specimens. One hundred and ninety three (82.1%) of them were defined as E. faecalis, 33 (14.0%) E. faecium, 1/235 (0.4%) E. avium, 1/235 (0.4%) E. raffinosus and 7/235 (3.0%) E. galinarium. The prevalence of vancomycin resistance was 13.6% (32/235) consisting of 18/235 (7.7%) E. faecalis and 6.0% (14/235) E. faecium. Among the 32 VRE strains, a total of 36 vanA and vanB genes were detected (some isolates had both vanA and vanB genes). These resistance genes were not detected in 5 out of 32 (15.6%) isolates. Conclusion: E. faecalis was more common in clinical samples and vanA (58.3%) gene was the predominant gene among the VRE isolates. The current study showed that Taq Man real time PCR assay is the useful, precise and rapid detection of vancomycin resistance genes.
Avicenna Journal of Clinical Microbiology and Infection, 2014
Background: In recent decades, bacterial antibiotic resistance (especially in enterococci) has become a significant problem for human and veterinary medicine. One of the most important antibiotic resistances in enterococci, vancomycin resistance, is encoded by van gene family. Objectives: The aim of this study was to investigate antibiotic resistance to vancomycin in enterococci and the genes responsible for this resistance. Materials and Methods: Two-hundred and thirty enterococcal isolates from pigs (207 isolates), chickens (15 isolates) and humans (eight isolates) were phenotypically and genotypically tested for resistance to vancomycin by minimum inhibitory concentration (MIC) and polymerase chain reaction (PCR). The van genes were confirmed by gene sequencing. Results: Of the total isolates, 19% were phenotypically resistant to vancomycin, while nearly 15% contained either vanC1 or vanC2 gene. One resistant E. casseliflavus isolate with pig origin (MIC > 8 μg/mL) contained both vanC1 and vanC2 genes. Furthermore, one vanC1 was found in a sensitive E. faecalis isolate of pig origin (MIC ≤ 4 μg/mL) and one vanC2 in a resistant E. faecium isolate of chicken origin (MIC > 32 μg/mL). These genes were not accompanied by other van genes. Other detected genes were vanA in 11 E. faecium isolates of chicken origin (MIC > 32 μg/mL). No vanB genes were found. Gene sequencing results showed 100% identity with GenBank reference genes. Conclusions: The current report is the first report on the detection of vanC1 and vanC2 genes in one enterococcal species with pig origin. This report is important as it proves the horizontal transfer of various vanC genes to one species possibly due to the compatibility class of plasmids. Furthermore, detection of vanC genes in E. faecalis and E. faecium isolates is important as it suggests that resistance to vancomycin in non-motile enterococci can be encoded by several mechanisms.