title: The redox potential interferes with the expression of laminin binding molecules in Bacteroides fragilis.
abstract: The Bacteroides fragilis ATCC strain was grown in a synthetic media with contrasting redox potential (Eh) levels [reduced (-60 mV) or oxidised (+100 mV)] and their adhesion capacity to extracellular matrix components was evaluated. The strain was capable of adhering to laminin, fibronectin, fibronectin + heparan sulphate and heparan sulphate. A stronger adherence to laminin after growing the strain under oxidising conditions was verified. Electron microscopy using ruthenium red showed a heterogeneous population under this condition. Dot-blotting analyses confirmed stronger laminin recognition by outer membrane proteins of cells cultured at a higher Eh. Using a laminin affinity column, several putative laminin binding proteins obtained from the cultures kept under oxidising (60 kDa, 36 kDa, 25 kDa and 15 kDa) and reducing (60 kDa) conditions could be detected. Our results show that the expression of B. fragilis surface components that recognise laminin are influenced by Eh variations.
authors.affiliation: Laboratório de Biologia de Anaeróbios, Departamento de Microbiologia Médica, IMPPG, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil. eliane_ferreirarj@yahoo.com
authors.forename: Eliane de Oliveira
authors.initials: Ede O
authors.lastname: Ferreira
authors.forename: Edwin Alexander
authors.initials: EA
authors.lastname: Yates
authors.forename: Morris
authors.initials: M
authors.lastname: Goldner
authors.forename: Rossiane Cláudia
authors.initials: RC
authors.lastname: Vommaro
authors.forename: Fernando Costa e
authors.initials: FC
authors.lastname: Silva Filho
authors.forename: Débora Barreiros
authors.initials: DB
authors.lastname: Petrópolis
authors.forename: Regina M C Pilotto
authors.initials: RM
authors.lastname: Domingues
mesh_terms: D000911:Antibodies, Monoclonal; D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D001441:Bacteroides fragilis / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure; D002352:Carrier Proteins / Q000378:metabolism*; D005109:Extracellular Matrix / Q000378:metabolism; D015151:Immunoblotting; D007797:Laminin / Q000378:metabolism*; D046529:Microscopy, Electron, Transmission; D010084:Oxidation-Reduction; D011135:Polysaccharides, Bacterial / Q000378:metabolism; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; D007797:Laminin; D011135:Polysaccharides, Bacterial