title: The giant extracellular matrix-binding protein of Staphylococcus epidermidis mediates biofilm accumulation and attachment to fibronectin.
abstract: Virulence of nosocomial pathogen Staphylococcus epidermidis is essentially related to formation of adherent biofilms, assembled by bacterial attachment to an artificial surface and subsequent production of a matrix that mediates interbacterial adhesion. Growing evidence supports the idea that proteins are functionally involved in S. epidermidis biofilm accumulation. We found that in S. epidermidis 1585v overexpression of a 460 kDa truncated isoform of the extracellular matrix-binding protein (Embp) is necessary for biofilm formation. Embp is a giant fibronectin-binding protein harbouring 59 Found In Various Architectures (FIVAR) and 38 protein G-related albumin-binding (GA) domains. Studies using defined Embp-positive and -negative S. epidermidis strains proved that Embp is sufficient and necessary for biofilm formation. Further data showed that the FIVAR domains of Embp mediate binding of S. epidermidis to solid-phase attached fibronectin, constituting the first step of biofilm formation on conditioned surfaces. The binding site in fibronectin was assigned to the fibronectin domain type III12. Embp-mediated biofilm formation also protected S. epidermidis from phagocytosis by macrophages. Thus, Embp is a multifunctional cell surface protein that mediates attachment to host extracellular matrix, biofilm accumulation and escape from phagocytosis, and therefore is well suited for promoting implant-associated infections.
authors: Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
authors: Martin
authors: M
authors: Christner
authors: Gefion C
authors: GC
authors: Franke
authors: Nina N
authors: NN
authors: Schommer
authors: Ulrike
authors: U
authors: Wendt
authors: Kim
authors: K
authors: Wegert
authors: Philip
authors: P
authors: Pehle
authors: Gesche
authors: G
authors: Kroll
authors: Christian
authors: C
authors: Schulze
authors: Friedrich
authors: F
authors: Buck
authors: Dietrich
authors: D
authors: Mack
authors: Martin
authors: M
authors: Aepfelbacher
authors: Holger
authors: H
authors: Rohde
mesh_terms: D020816:Amino Acid Motifs; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D018441:Biofilms / Q000254:growth & development*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism*; D017353:Gene Deletion; D006801:Humans; D008264:Macrophages / Q000276:immunology / Q000382:microbiology; D010587:Phagocytosis; D011485:Protein Binding; D025941:Protein Interaction Mapping; D013212:Staphylococcus epidermidis / Q000276:immunology / Q000378:metabolism / Q000472:pathogenicity / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; C469919:Embp32 protein, Staphylococcus epidermidis; D005353:Fibronectins