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New ecosystems are being actively mined for new bioactive compounds. Because of the large amount of unexplored biodiversity, bacteria from marine environments are especially promising. Further, host-associated microbes are of special interest because of their low toxicity and compatibility with host health. Here, we identified and characterized biosynthetic gene clusters encoding antimicrobial compounds in host-associated enterococci recovered from fecal samples of wild marine animals remote from human-affected ecosystems. Putative biosynthetic gene clusters in the genomes of 22 Enterococcus strains of marine origin were predicted using antiSMASH5 and Bagel4 bioinformatic software. At least one gene cluster encoding a putative bioactive compound precursor was identified in each genome. Collectively, 73 putative antimicrobial compounds were identified, including 61 bacteriocins (83.56%), 10 terpenes (13.70%), and 2 (2.74%) related to putative nonribosomal peptides (NRPs). Two of the species studied, Enterococcus avium and Enterococcus mundtti, are rare causes of human disease and were found to lack any known pathogenic determinants but yet possessed bacteriocin biosynthetic genes, suggesting possible additional utility as probiotics. Wild marine animal-associated enterococci from human-remote ecosystems provide a potentially rich source for new antimicrobial compounds of therapeutic and industrial value and potential probiotic application.

Background and Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most frequent causes of healthcare-associated and community-acquired infections and with its advancement, vancomycin became the main therapeutic option. However, its indiscriminate 2 use favored the emergence of MRSA with reduced susceptibility to vancomycin, commonly associated with vancomycin treatment failure, persistent bacteremia, prolonged hospitalization and adverse clinical outcome. This study evaluated the occurrence of MRSA with reduced vancomycin susceptibility and determined some molecular characteristics in comparison with vancomycin-susceptible MRSA (VS-MRSA). Methods: Determination of antimicrobial susceptibility profile, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for vancomycin, vancomycin-tolerance, SCCmec and agr typing were performed in a total of 177 MRSA. Thereafter, they were screened for hVISA by BHIA-3V and BHIA-6V and confirmed with population analysis profile - area under the curve method (PAPAUC). Results: VT-MRSA and hVISA phenotypes were found in 13.6% and 5.1% of clinical isolates of MRSA, respectively, and the presence of hVISA was statistically significant among VT-MRSA isolates (p Justificación y objetivos: Staphylococcus aureus resistente a la meticilina (MRSA) es una de las causas más frecuentes de infecciones relacionadas con la asistencia sanitaria y comunitarias, y con su avance, a la vancomicina se ha convertido en la principal opción terapéutica. Sin embargo, su uso indiscriminado favoreció el surgimiento de MRSA con reducida susceptibilidad a la vancomicina, comúnmente asociados con fallas en el tratamiento, bacteriemia persistente, hospitalización prolongada y resultados clínicos adversos. Este estudio evaluó la ocurrencia de MRSA con reducida susceptibilidad a la vancomicina y determinó algunas características moleculares en comparación con MRSA susceptible a la vancomicina (VS-MRSA). Métodos: Determinación del perfil de susceptibilidad a los antimicrobianos, la concentración inhibitoria mínima (CIM) y la concentración bactericida mínima (CBM) para vancomicina, tolerancia a la vancomicina, tipificación del SCCmec y agr se realizaron en un total de 177 MRSA. Resultados: Los fenotipos VT-MRSA y hVISA se encontraron en el 13,6% y el 5,1% de los aislados clínicos de MRSA, respectivamente, y la presencia de hVISA fue estadísticamente significativa entre los aislados de VT-MRSA (p Justificativa e Objetivos: Staphylococcus aureus resistente à meticilina (MRSA) é uma das causas mais frequentes de infecções relacionadas à assistência à saúde e comunitárias, e com seu avanço, a vancomicina tornou-se a principal opção terapêutica. Entretanto, o seu uso indiscriminado favoreceu o surgimento de MRSA com reduzida suscetibilidade à vancomicina, comumente associados com falhas no tratamento, bacteremia persistente, hospitalização prolongada e desfechos clínicos adversos. Este estudo avaliou a ocorrência de MRSA com reduzida suscetibilidade à vancomicina e determinou algumas características moleculares em comparação com MRSA suscetível à vancomicina (VS-MRSA). Métodos: Determinação do perfil de suscetibilidade aos antimicrobianos, a concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM) para vancomicina, tolerância à vancomicina, tipagem do SCCmec e agr foram realizadas em um total de 177 MRSA. Posteriormente, foram triados para hVISA por BHIA-3V e BHIA-6V e confirmados com a Análise do Perfil Populacional - Área Abaixo da Curva (PAP-AUC). Resultados: Os fenótipos VT-MRSA e hVISA foram encontrados em 13,6% e 5,1% dos isolados clínicos de MRSA, respectivamente, e a presença de hVISA foi estatisticamente significativa entre os isolados de VT-MRSA (p

Rapid identification of vancomycin-resistant enterococci (VRE) can assist in choosing the appropriate treatment and preventing VRE spread. The performance of chromIDTM VRE agar was evaluated using 184 clinical isolates of Enterococcus spp. and reference strains. The test had a sensitivity of 95.52% but a low specificity of 30%.

Background and Objective: The buffalo milk consumption and derivatives have increased significantly in the last year due to the healthy food demand. Enterococci play a beneficial role during the maturation of some cheese and sausages; they have been used as probiotics in humans and animals. On the other hand, they are indicators of fecal contamination and are frequently associated with foodborne illnesses by biogenic amines. The aim of this study was to evaluate the presence of virulence profiles in enterococci strains isolated from raw buffalo’s milk samples. Materials and Methods: Seventy-nine enterococci species were selected which previously identified by conventional biochemical methods. The strains were submitted to genotypic identification using genus-specific and species-specific primers. Strains were tested for the presence of virulence genes (agg , ace , gelE ) by PCR, their ability to form biofilms and to produce the enzyme gelatinase by phenotypic methods. The optical density (OD) of bacterial biofilms was quantified in a spectrophotometer. Results: The phenotypic and genotypic identification were similar in more than 96% of the strains. The frequency of ace (96 vs. 10.34%) and gelE (96 vs. 17.24%) genes were higher in E. faecalis than in E. faecium, while the agg gene was detected only in E. faecalis strains (26%). The in vitro biofilm ability was observed in both strains; however, it was superior among E. faecalis (90%) than in E. faecium (24.1%). The presence of gelE and the activity of gelatinase were not fully concordant. Conclusion: It was concluded that the presences of enterococci harboring virulent factors in raw buffalo’s milk suggest a situation of risk for the community, since enterococci are opportunist pathogens. The ability to form biofilm is important for food safety and the protection of public health. In this sense, the present study sought to collaborate with the status quo of scientific knowledge to improve safety and quality of the food for human consumption.

Enterococcus faecalis do not only inhabit the intestines of many animals, but also food and the environment. These microorganisms have intrinsic ability which enables them to persist in different environments. The aims of our study were (i) to carry out a comparative analysis of tetracycline resistance and virulence factor genes of Enterococcus faecalis isolates from food, poultry and clinical samples and (ii) to determine the genetic relationships of these factors among these isolates. A total of 182 E. faecalis were studied; 70, 52, and 60 strains were isolated from clinical samples, broiler cloacal swabs and food, respectively. Enterococcus faecalis isolates were submitted to research genes for virulence factors tet (L), tet (M), (bop ABCD, ace and agg) by PCR and grouped into clusters according to their genotype. The prevalence among all the genes studied could be considered high, ranging from 61.5 to 99.4% of the virulence factors of genes and 19.2 to 70.3% of the antimicrobial resistance genes, tet (L) and tet (M), respectively, where it was possible to obtain different genetic profiles. The enterococci isolated from food, humans and broiler cloacal swabs showed high genetic diversity, although some strains seemed to be closely related. The 182 isolates formed twelve different clusters independent of the origin of the samples or the diets used in the feeding of broilers, with the similarity index value ranging from 0.16 to 1.0, similarity coefficient, 0.70. In conclusion, enterococci isolated from food, humans and broiler cloacal swabs are genetically different. In addition, the analysis of virulence factors genes and tet genes by PCR proved to be an effective methodology for determining the microbial diversity of Enterococcus faecalis isolates of different environmental sources.

Introduction: Exposure to subinhibitory concentrations (SICs) of antimicrobials may alter the bacterial transcriptome. Methods: Here, we evaluated the expression of nine virulence-related genes in vancomycin-resistant enterococci (VRE) urinary tract infection isolates grown at SICs of vancomycin. Results: A Subinhibitory concentrations of vancomycin interferes with gene modulation, but does not affect the phenotype of a VRE strain in vitro. Conclusions: Subinhibitory concentrations of vancomycin may regulate the expression of virulence factors in vivo or contribute to the selection of vancomycin-resistant strains.

Introduction: Enterococci have become the third major leading cause of nosocomial bacteraemia, an infection which is significantly associated with the risk of developing infective endocarditis. Linezolid provides high rates of clinical cure and microbiologic success in complicated infections due to Enterococcus spp. However, several instances of emergence of resistance during linezolid treatment have been reported. The aim of this study was evaluate the activity of tigecycline against Linezolid-Intermediate (LIE) and Linezolid-Resistant Enterococcus faecalis (LRE) by the time-kill assay. Methods: Five isolates of LRE and two isolates of LIE were used in this study. MICs were determined by broth dilution following the CLSI (2014) guidelines. Time-kill assay was employed to access the in vitro response profile of tigecycline. Results: All seven of the isolates presented MIC of 0.125μg/mL. Tigecycline activity was individually evaluated and in three of the five isolates of LRE it presented bactericidal. Against the other isolates, tigecycline showed bacteriostatic activity. The tigecycline activity was measured according to CLSI criteria. Conclusions: Tigecycline presented both bacteriostatic and bactericidal activity against tested isolates, result not yet described in previous studies. Time and concentrations above MIC were key factors to achieving bactericidal effect. MIC and the tested concentration below it resulted in bacteriostatical effect to enterococci, corroborating previous data.

Infections caused by Streptococcus pneumoniae are a worrisome public health problem worldwide. Young children and elderly are the main age group affected and the highest burden of the disease are among developing countries. Pneumococcal infections cause 11% of the total of infant deaths, representing the leading cause of child death currently preventable by vaccination. Epidemiologic information about pneumococci in Brazil is somehow restrict, but available data reinforce the worrisome occurrence of pneumococcal diseases, which are commonly treated empirically. Limitations in the diagnostic methods, along with the severity of disease contribute to this behavior. Thus, surveillance studies are crucial to define the prevalence of resistant strains both globally or in a particular region, as these strains may compromise empirical therapeutical choices. However, although different clones of PNSP are internationally distributed, and considering diseases other than meningitis, the prevalence to penicillin is quite low, making this old, safe, and inexpensive drug an attractive first choice to treat pneumococcal infections. The widespread use of conjugate vaccines among children, influencing the circulation of resistant clones and the distribution of serotypes reinforces the need of surveillance studies to define prevalence of resistance., Infections caused by Streptococcus pneumoniae are a worrisome public health problem worldwide. Young children and the elderly are the main age groups affected and the highest burden of the disease is found in developing countries. Pneumococcal infections cause 11% of the total infant deaths, representing the leading cause of child death currently preventable by vaccination. Epidemiologic information about pneumococci in Brazil is somehow restricted, but available data reinforce the worrisome occurrence of pneumococcal diseases, which are commonly treated empirically. Limitations in the diagnostic methods, along with the severity of disease contribute to this behavior. Thus, surveillance studies are crucial to define the prevalence of resistant strains both globally and in a particular region, as these strains may compromise empirical therapeutic choices. However, although different clones of penicillin non-susceptible pneumococci are internationally distributed, and considering diseases other than meningitis, the prevalence of resistance to penicillin is quite low, making this old, safe, and inexpensive drug an attractive first choice to treat pneumococcal infections. The widespread use of conjugate vaccines among children, influencing the circulation of resistant clones and the distribution of serotypes reinforces the need of surveillance studies to define the prevalence of resistance.

Here we report the presence and expression levels of the vanC1 and vanC2/3 genes in vancomycin-susceptible strains of Enterococcus faecalis. The vanC1 and vanC2/3 genes were located in the plasmid DNA and on the chromosome, respectively. Specific mRNA of the vanC1 gene was detected in one of these strains. Additionally, analysis of the vanC gene sequences showed that these genes are related to the vanC genes of Enterococcus gallinarum and Enterococcus casseliflavus. The presence of vanC genes is useful for the identification of E. gallinarum and E. casseliflavus. Moreover, this is the first report of vanC mRNA in E. faecalis.

O objetivo do presente trabalho foi determinar a frequência das espécies de enterococos das águas do arroio Dilúvio, em Porto Alegre, RS, bem como avaliar o perfil susceptibilidade frente a antimicrobianos de importância clínica e veterinária. No período de março a dezembro de 2009, foram coletadas amostras de águas do arroio em cinco pontos distintos, as quais foram submetidas à avaliação microbiológica. Trezentos e quarenta e oito enterococos foram isolados das amostras de água coletadas nos cinco pontos ao longo do curso do arroio Dilúvio e identificados em nível de espécie por provas bioquímicas e PCR. A espécie E. faecium (68,67%) foi a mais frequente, seguida de E. faecalis (16,09%), E. casseliflavus (12,07%), E. hirae (2,58%) e E.gallinarum (0,57%). Nos pontos 1 e 3 não houve diferença significativa entre as espécies. Os resultados dos testes de susceptibilidade aos antimicrobianos pelo método de difusão em disco revelaram que a maioria das bactérias era resistente a eritromicina (81,07%), nitrofurantoína (37,26%), norfloxacina (34,82%), ciprofloxacina (32,55%), cloranfenicol (4,73), tetraciclina (2,23%) e vancomicina (0,28%). Foi observada uma diferença significativa nos Pontos 4 e 5 quanto ao número médio de enterococos resistentes aos antibióticos testados (P= 0,0174).Todos os isolados foram sensíveis a ampicilina e a gentamicina. Espécies multirresistentes aos antimicrobianos foram observadas. Os resultados do presente estudo demonstram que as águas do arroio Dilúvio podem ser uma fonte de disseminação e persistência de enterococos resistentes e de seus genes de resistência aos antimicrobianos para os seres humanos e meio ambiente, representando riscos à população. The aim of this study was to determine the frequency enterococci species from Dilúvio stream, in Porto Alegre RS, and the antimicrobial susceptibility profiles of the isolates to antibiotics of human and veterinary importance. From March to December 2009, water samples were collected from the stream into five distinct points. Three hundred and forty eight enterococci were isolated from water samples collected at five points along the course of the creek flood and identified to the species level through their phenotypic profiles and PCR. The most frequent specie was E. faecium (68.67%), followed by E. faecalis (16.09%), E. casseliflavus (12.07%), E. hirae (2.58%) and E.gallinarum (0.57%). Points 1 and 3 showed no significant differences between the species. The antimicrobial susceptibility tests revealed that isolateswereresistant to erythromycin (81.07%), nitrofurantoin (37.26%), norfloxacin (34.82%), ciprofloxacin (32.55%), chloramphenicol (4.73), tetracycline (2.23%) and vancomycin (0.28%). There was a significant differences in the prevalence of antibiotic-resistant enterococci in the Points 4 and 5 (P