The redox potential interferes with the expression of laminin binding molecules in Bacteroides fragilis.
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.
Ferreira
Eliane de Oliveira
Ede O
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
Yates
Edwin Alexander
EA
Goldner
Morris
M
Vommaro
Rossiane Cláudia
RC
Silva Filho
Fernando Costa e
FC
Petrópolis
Débora Barreiros
DB
Domingues
Regina M C Pilotto
RM
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
D000911:Antibodies, Monoclonal; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; D007797:Laminin; D011135:Polysaccharides, Bacterial