Molecular detection of virulence factors among food and clinical Enterococcus faecalis strains in South Brazil

Abstract

The present report aimed to perform a molecular epidemiological survey by investigating the presence of virulence factors in E. faecalis isolated from different human clinical (n = 57) and food samples (n = 55) in Porto Alegre, Brazil, collected from 2006 to 2009. In addition, the ability to form biofilm in vitro on polystyrene and the β-haemolytic and gelatinase activities were determined. Clinical strains presented a higher prevalence of aggregation substance (agg), enterococcal surface protein (esp) and cytolysin (cylA) genes when compared with food isolates. The esp gene was found only in clinical strains. On the other hand, the gelatinase (gelE) and adherence factor (ace) genes had similar prevalence among the strains, showing the widespread occurrence of these virulence factors among food and clinical E. faecalis strains in South Brazil. More than three virulence factor genes were detected in 77.2% and 18.2% of clinical and food strains, respectively. Gelatinase and β-haemolysin activities were not associated with the presence of gelE and cylA genes. The ability to produce biofilm was detected in 100% of clinical and 94.6% of food isolates, and clinical strains were more able to form biofilm than the food isolates (Student’s t-test, p < 0.01). Results from the statistical analysis showed significant associations between strong biofilm formation and ace (p = 0.015) and gelE (p = 0.007) genes in clinical strains. In conclusion, our data indicate that E. faecalis strains isolated from clinical and food samples possess distinctive patterns of virulence factors, with a larger number of genes that encode virulence factors detected in clinical strains.

Evaluation antibacterial and antibiofilm activity of the antimicrobial peptide P34 against Staphylococcus aureus and Enterococcus faecalis

“…The hygienic condition of food handlers is also associated with the propagation of S. aureus biofilm producer (Gutiérrez et al 2012, Souza et al 2014, Di Ciccio et al 2015. Several authors have reported E. faecalis strains isolated from food samples with ability to form biofilms (Medeiros et al 2014, Jahan and Holley 2014, Fernandes et al 2015. Apparently, the biofilm formation by this bacterial species is influenced by several aspects, such as temperature, exposure to nutrients and sanitizers, and surface characteristics (Marinho et al 2013, Fernandes et al 2015.…”

“…These strains were genotypically characterized by Medeiros et al (2014) that found the presence of gelatinase (gelE) and cytolysin (cylA) genes. Such virulence factors and phenotypic characteristics of each strain may be associated with metabolic stimulation.…”

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

“…It has been more persistently recognized in E. faecalis isolates (9). Medeiros et al (23) reported the invariant incidence of the ace gene among clinical and dairy products of E. faecalis. They have been distinguished the higher fre- Cytolysin operon is carried through plasmid or bacterial chromosome.…”

History, Virulence Genes, Identification and Antimicrobial Resistance of Enterococcus faecalis Isolated from Diabetic Foot Patients

“…Medeiros et al, (2014) Lemsaddek et al, 2016), stated that the pathogenesis of foot ulceration is complicated, the death is excessive and ulcers are frequently occurred and lead to severe and chronic infections of the foot. Most DFIs have a poly-microbial etiology, enterococcal strains actuality portion of the multifaceted diabetic foot microbiota.…”