title: Inhibition by EGTA of the formation of a biofilm by clinical strains of Staphylococcus aureus.
abstract: The effect of EGTA on the adhesion and on the formation of a biofilm by two reference and eight clinical strains of Staphylococcus aureus was studied. All the clinical strains were isolated from patients from Kinshasa. Spa typing confirmed that these clinical strains were distinct. The Biofilm Ring Test (BFRT®) showed that EGTA (100 µM-10 mM) inhibited the adhesion of the four clinical methicillin-resistant (MRSA) strains and the crystal violet staining method that it inhibited the formation of a biofilm by all the strains. Divalent cations abolished the effect of EGTA on the formation of a biofilm, specially in the clinical MRSA strains. EGTA had no effect on established biofilms. Only concentrations of EGTA higher than 10 mM were toxic to eukaryotic cells. Our results establish the effectiveness and the safety of lock solutions with EGTA to prevent the formation in vitro of biofilms by S. aureus.
authors.affiliation: Laboratoire de Chimie Biologique et Médicale et de Microbiologie Pharmaceutique, Faculté de Pharmacie, Université Libre de Bruxelles, Brussels, Belgium; Laboratoire de Microbiologie Expérimentale et Pharmaceutique, Faculté des Sciences Pharmaceutiques, Université de Kinshasa, Kinshasa, Democratic Republic of Congo.
authors.forename: J M
authors.initials: JM
authors.lastname: Liesse Iyamba
authors.forename: M
authors.initials: M
authors.lastname: Seil
authors.forename: C
authors.initials: C
authors.lastname: Nagant
authors.forename: S
authors.initials: S
authors.lastname: Dulanto
authors.forename: A
authors.initials: A
authors.lastname: Deplano
authors.forename: C
authors.initials: C
authors.lastname: El Khattabi
authors.forename: N B
authors.initials: NB
authors.lastname: Takaisi Kikuni
authors.forename: J P
authors.initials: JP
authors.lastname: Dehaye
mesh_terms: D001422:Bacterial Adhesion / Q000187:drug effects; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D002118:Calcium / Q000494:pharmacology; D002413:Cations, Divalent; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004269:DNA, Bacterial / Q000235:genetics*; D004305:Dose-Response Relationship, Drug; D004533:Egtazic Acid / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D015870:Gene Expression; D006801:Humans; D008264:Macrophages / Q000166:cytology / Q000187:drug effects; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D013203:Staphylococcal Infections / Q000382:microbiology
chemical_list: D001425:Bacterial Outer Membrane Proteins; D002413:Cations, Divalent; D004269:DNA, Bacterial; D008345:Manganese; D004533:Egtazic Acid; D008274:Magnesium; D002118:Calcium
keywords: Biofilm Ring test®; Crystal violet; MTT test; Staphylococcus aureus biofilm; spa typing