Enterococcus faecalis Cell-Free Supernatant Inhibits Hyphal Morphogenesis and Biofilm Formation in Candida albicans

Abstract

Enterococcus faecalis and Candida albicans are two of the most significant opportunistic and intricate nosocomial pathogens. They reside overlapping niches as major constituents of the gastrointestinal (GI) and oral microbiome. This study was designed to investigate the interaction between these two opportunistic pathogens that could affect treatment strategies and influence the interkingdom signaling and sensing in the microbiome conceptions. E. faecalis was isolated from 150 samples collected from human urine, cattle raw milk, milk products and chicken intestine and identified by both the routine microbiological and molecular identification methods based on 16S rRNA gene. Isolates susceptibility to nine antimicrobials was analyzed using the disk-diffusion method and E. faecalis isolates showed multidrug resistance. Most of C. albicans isolates were able to form biofilm with different intensities. Cell-free supernatant (CFS) of E. faecalis was purified and tested against C. albicans and/or biofilm formation. It inhibited the growth of C. albicans and their filamentation with regards to biofilm formation in vitro. The data presented here demonstrated the potential antifungal activity of E. faecalis CFS and could explain the biological interaction between these two microbes in one hand and the possibility of using E. faecalis CFS as a biological product to control yeast infection in the other hand.

Candida albicans and Enterococcus faecalis biofilm frenemies: When the relationship sours

“…In this new study we describe changes in C. albicans growth, phenotype, virulence and transcriptome when co-cultured with E. faecalis in vitro . In agreement with previous in vitro and in vivo studies, our preliminary investigation showed an inhibition of C. albicans growth, hyphal morphogenesis and biofilm formation in dual-species biofilms [ 18 , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] ]. Subsequent RNASeq showed that E. faecalis rapidly and significantly alters C. albicans gene expression.…”

“…First, we investigated the general effect of E. faecalis on C. albicans hyphal morphogenesis, biofilm formation, growth, and expression of key genes related to biofilm formation, virulence and drug resistance. C. albicans SC5314, HBF and LBF were grown in mono-species biofilms or co-cultured with E. faecalis ER5/1 for 24 h. As reported by various studies [ 33 , 34 , 36 , 38 , 39 ], C. albicans hyphal morphogenesis was shown to be clearly inhibited in co-cultures, as shown in calcofluor stained images ( Fig. 1 a).…”

“…E. faecalis inhibition of C. albicans hyphal morphogenesis, biofilm formations and virulence are reported in various studies [ 33 , 34 , 36 , 38 , 39 ]. However, few investigated the mechanism of this interaction.…”

“…RNASeq has been extensively used to analyse how C. albicans responds under these circumstances, which has dramatically enhanced our understanding of the transcriptional profiles of C. albicans response to weak organic acids [ 29 ], growth media, oxidative and nitrosative stresses [ 30 ], Lactobacillus [ 31 ], Streptococcus gordonii [ 7 ], Pseudomonas aeruginosa quorum sensing molecules [ 32 ], amongst others. The interaction between C. albicans and E. faecalis , and more specifically the effect of E. faecalis and its supernatant on C. albicans morphogenesis, biofilm formation and virulence has been the subject of several investigations [ 18 , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] ]. It was proposed that E. faecalis secretes an anti-candidal protein [ 40 ], and that it is the EntV bacteriocin that is specifically linked to the observed C. albicans inhibition [ 34 ].…”

Promising Anti-Biofilm Agents and Phagocytes Enhancers for the Treatment of Candida albicans Biofilm–Associated Infections

“…Clove and cinnamon EOs (Sigma Aldrich, St. Louis, MO, USA) were diluted in 1% dimethyl sulfoxide (DMSO, Sigma) (Shahzad et al, 2014). The CFS of E. faecalis used in this study was purified using ammonium sulfate precipitation and dialysis from two strains in our previous study (Hassan et al, 2018). These strains were isolated from cheddar cheese (CFS1) and chicken intestine (CFS2) samples.…”