New Insights into the Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus Host Interaction Mechanisms

• Published in: PloS one Vol. 11; no. 7; p. e0159159
• Main Authors: Sánchez-Díaz, Ana María, Romero-Hernández, Beatriz, Conde-Moreno, Elisa, Kwak, Young-Keun, Zamora, Javier, Colque-Navarro, Patricia, Möllby, Roland, Ruiz-Garbajosa, Patricia, Cantón, Rafael, García-Bermejo, Laura, Del Campo, Rosa
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 27-07-2016; Public Library of Science (PLoS)
• Subjects: Analysis; Antibiotics; Bacteremia; Bacteria; Biofilms; Biology and Life Sciences; Caco-2 Cells; Causes of; Cloning; Collagen (type I); Collagen (type IV); Colorectal cancer; Colorectal carcinoma; Destabilization; Development and progression; Endocarditis; Enterococcus; Enterococcus faecium; Enterococcus faecium - physiology; Health aspects; Hospitals; Host-bacteria relationships; Host-Pathogen Interactions; Humans; Infections; Intestine; Life sciences; Measurement techniques; Medicin och hälsovetenskap; Medicine and Health Sciences; Nosocomial infection; Opportunist infection; Pathogens; Permeability; Physiological aspects; Polystyrene; Polystyrene resins; Proteins; Reclassification; Research and Analysis Methods; Streptococcus; Streptococcus bovis; Streptococcus gallolyticus; Streptococcus gallolyticus - physiology; Streptococcus infections; Translocation; Transplants & implants; Vegetation establishment; United States > US; Sweden; Spain
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0159159

Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) were classically clustered into the Lancefield Group D streptococci and despite their taxonomic reclassification still share a similar genetic content and environment. Both species are considered as opportunistic pathogens. E. faecium is often associated with nosocomial bacteraemia, and S. gallolyticus is sporadically found in endocarditis of colorectal cancer patients. In both cases, the source of infection is commonly endogenous with a translocation process that launches through the intestinal barrier. To get new insights into the pathological processes preceding infection development of both organisms, we used an in vitro model with Caco-2 cells to study and compare the adhesion, invasion and translocation inherent abilities of 6 E. faecium and 4 S. gallolyticus well-characterized isolates. Additionally, biofilm formation on polystyrene, collagen I and IV was also explored. Overall results showed that E. faecium translocated more efficiently than S. gallolyticus, inducing a destabilization of the intestinal monolayer. Isolates Efm106, Efm121 and Efm113 (p < .001 compared to Ef222) exhibited the higher translocation ability and were able to adhere 2-3 times higher than S. gallolyticus isolates. Both species preferred the collagen IV coated surfaces to form biofilm but the S. gallolyticus structures were more compact (p = .01). These results may support a relationship between biofilm formation and vegetation establishment in S. gallolyticus endocarditis, whereas the high translocation ability of E. faecium high-risk clones might partially explain the increasing number of bacteraemia.