Genetic Diversity among Enterococcus faecalis

Abstract

Enterococcus faecalis, a ubiquitous member of mammalian gastrointestinal flora, is a leading cause of nosocomial infections and a growing public health concern. The enterococci responsible for these infections are often resistant to multiple antibiotics and have become notorious for their ability to acquire and disseminate antibiotic resistances. In the current study, we examined genetic relationships among 106 strains of E. faecalis isolated over the past 100 years, including strains identified for their diversity and used historically for serotyping, strains that have been adapted for laboratory use, and isolates from previously described E. faecalis infection outbreaks. This collection also includes isolates first characterized as having novel plasmids, virulence traits, antibiotic resistances, and pathogenicity island (PAI) components. We evaluated variation in factors contributing to pathogenicity, including toxin production, antibiotic resistance, polymorphism in the capsule (cps) operon, pathogenicity island (PAI) gene content, and other accessory factors. This information was correlated with multi-locus sequence typing (MLST) data, which was used to define genetic lineages. Our findings show that virulence and antibiotic resistance traits can be found within many diverse lineages of E. faecalis. However, lineages have emerged that have caused infection outbreaks globally, in which several new antibiotic resistances have entered the species, and in which virulence traits have converged. Comparing genomic hybridization profiles, using a microarray, of strains identified by MLST as spanning the diversity of the species, allowed us to identify the core E. faecalis genome as consisting of an estimated 2057 unique genes.

Estudo da ação antibacteriana do extrato hidroalcoólico de própolis vermelha sobre Enterococcus faecalis

“…Para a avaliação antimicrobiana, foi utilizado o meio de cultura Ágar Brain Heart Infusion (BHI-ágar) 35 . Utilizou-se como controle positivo a solução de hipoclorito de sódio a 2,5% e, como controle negativo, a água destilada estéril.…”

Determination of Virulence Factors in Clinical Multidrug Resistance Enterococci Isolates at Southeast of Iran

“…Glycopeptide resistance is encoded by the van operon and can be partitioned into several types, of which the most broadly reported are tralize synergistic properties (the combined β-lactam or glycopeptide and an aminoglycoside) and leading to failure treatment in threatening enterococcal infections (7). Therefore, enterococci are noteworthy because of multiple drug resistance, nosocomial infections, and particularly being capable of transferring antibiotic resistant genes to other microbes (8).…”

Bacterial contamination of public telephones in the downtown area of Sarajevo

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