Molecular characterisation by infrared spectroscopy of Bordetella pertussis grown as biofilm

It is known that bacterial adhesion to tissues plays an important role in m icrobial infection and that organisms attached to a surface can express a c haracteristic phenotype. Although Bordetella pertussis, the etiological age nt of whooping cough, has adapted itself to colonise the human respiratory tracts, most of the studies of the expression of their virulence factors ha ve been obtained from bacteria cultivated as cell suspension in liquid medi a. In this work, we show that B. pertussis can grow attached to an abiotic surface and that this attachment stimulates the production of exopolymers ( slime) leading to the formation of biofilms. By using Fourier transform inf rared spectroscopy (FT-IR) analysis, we found that these biofilm-grown cell s are chemically different from the cells grown in both, liquid and solid m edia. Furthermore, we demonstrated that this slime is mainly composed of ca rbohydrates.