TITLE:
Virulence Factors and Biofilm Formation in Vancomycin Resistant Enterococcus faecalis and Enterococcus faecium Isolates in Brazil
AUTHORS:
Bárbara de Azevedo Ramos, Marília Manta Manta, Sivoneide Maria da Silva, Rafael Artur Queiroz Cavalcanti de Sá, Natália Lira de Souza, Henrique Douglas Melo Coutinho, Márcia Vanusa da Silva, Túlio Diego da Silva, Maria Tereza dos Santos Correia, Maria Betânia Melo de Oliveira
KEYWORDS:
Biofilm, Cellular Hydrophobicity, Gram-Positive, Hospital Environment, Virulence Genes
JOURNAL NAME:
Advances in Microbiology,
Vol.13 No.6,
June
20,
2023
ABSTRACT: In this work, we evaluated biofilm formation of Vancomycin Resistant of E. faecalis and E. faecium (VRE) in different culture media and adhesion substrate, as well as cellular hydrophobicity and presence of virulence genes. For this, 35 isolates were collected from a public hospital in Recife, Pernambuco, Brazil and identified by the Matrix-Assisted Laser Desorption Ionization - Time-of-flight - Mass Spectrometry (MALDI-TOF-MS) technique. Biofilm formation was analyzed by the Crystal Violet (CV) method and fluorescence microscopy, cellular hydrophobicity by hydrocarbon interaction and the presence of gelE, esp and asa1 genes by Polymerase Chain Reaction (PCR). 12 isolates were identified as E. faecalis and 23 as E. faecium. Most were obtained in Coronary Units (40.0%) and Intensive Care Unit (31.4%). E. faecium isolates were more resistant to the antibiotics tested than E. faecalis; however, E. faecalis stood out as a biofilm producer. Regarding the presence and gene frequency, it was observed that gelE (54.3%) and esp (54.3%) were the most prevalent, followed by asa1 (22.9%). When comparing the gene frequency, it was observed that gelE and esp were predominant (48.6% for both species), while asa1 was more frequent in E. faecalis (20.0%). The data presented here are worrying, because they reveal the virulence potential of isolates VRE, which contributes to the dissemination and persistence of these pathogens in the hospital environment.