title: In vitro effect of temperature on the conformational structure and collagen binding of SdrF, a Staphylococcus epidermidis adhesin.
abstract: Staphylococcus epidermidis is the leading etiologic agent of device-related infections. S. epidermidis is able to bind, by means of the adhesins of its cell wall, the host matrix proteins filming the artificial surfaces. Thence, bacteria cling to biomaterials and infection develops. The effect of temperature on integrity, structure, and biological activity of the collagen-binding adhesin (SdrF) of S. epidermidis has been here investigated. By cloning in E. coli XL1-Blue, a recombinant of the SdrF binding domain B (rSdrFB), carrying an N-terminal polyhistidine, was obtained. Purification was by HiTrap(TM) Chelating HP columns. Assessment of purity, molecular weight, and integrity was by SDS-PAGE. The rSdrFB-collagen binding was investigated by ELISA. A full three-dimensional reconstruction of rSdrFB was achieved by small-angle X-ray scattering (SAXS). At 25 °C, rSdrFB bound to type I collagen in a dose-dependent, saturable manner, with a Kd of 2.48 × 10(-7) M. When temperature increased from 25 to 37 °C, a strong conformational change occurred, together with the abolition of the rSdrFB-collagen binding. The rSdrFB integrity was not affected by temperature variation. SdrFB-collagen binding is switched on/off depending on the temperature. Implications with the infection pathogenesis are enlightened.
authors: Department of Molecular Medicine, Center for Tissue Engineering (CIT), INSTM UdR of Pavia, University of Pavia, Viale Taramelli 3/b, 27100, Pavia, Italy.
authors: Antonella
authors: A
authors: Di Poto
authors: Massimiliano
authors: M
authors: Papi
authors: Sheetal
authors: S
authors: Trivedi
authors: Alessandro
authors: A
authors: Maiorana
authors: Paola
authors: P
authors: Gavazzo
authors: Massimo
authors: M
authors: Vassalli
authors: Franklin D
authors: FD
authors: Lowy
authors: Marco
authors: M
authors: De Spirito
authors: Lucio
authors: L
authors: Montanaro
authors: Marcello
authors: M
authors: Imbriani
authors: Carla Renata
authors: CR
authors: Arciola
authors: Livia
authors: L
authors: Visai
mesh_terms: D018829:Adhesins, Bacterial / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D003094:Collagen / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008970:Molecular Weight; D011485:Protein Binding / Q000528:radiation effects; D011487:Protein Conformation / Q000528:radiation effects*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D053838:Scattering, Small Angle; D013212:Staphylococcus epidermidis / Q000737:chemistry* / Q000235:genetics; D013696:Temperature
chemical_list: D018829:Adhesins, Bacterial; D011994:Recombinant Proteins; D003094:Collagen