Adhesive Surface Proteins ofErysipelothrix rhusiopathiaeBind to Polystyrene, Fibronectin, and Type I and IV Collagens

Abstract

Erysipelothrix rhusiopathiae is a gram-positive bacterium that causes erysipelas in animals and erysipeloid in humans. We found two adhesive surface proteins of E. rhusiopathiae and determined the nucleotide sequences of the genes, which were colocalized and designated rspA and rspB. The two genes were present in all of the serovars of E. rhusiopathiae strains examined. The deduced RspA and RspB proteins contain the C-terminal anchoring motif, LPXTG, which is preceded by repeats of consensus amino acid sequences. The consensus sequences are composed of 78 to 92 amino acids and repeat 16 and 3 times in RspA and RspB, respectively. Adhesive surface proteins of other gram-positive bacteria, including Listeria monocytogenes adhesin-like protein, Streptococcus pyogenes protein F2 and F2-like protein, Streptococcus dysgalactiae FnBB, and Staphylococcus aureus Cna, share the same consensus repeats. Furthermore, the N-terminal regions of RspA and RspB showed characteristics of the collagen-binding domain that was described for Cna. RspA and RspB were expressed in Escherichia coli as histidine-tagged fusion proteins and purified. The recombinant proteins showed a high degree of capacity to bind to polystyrene and inhibited the binding of E. rhusiopathiae onto the abiotic surface in a dose dependent manner. In a solid-phase binding assay, both of the recombinant proteins bound to fibronectin, type I and IV collagens, indicating broad spectrum of their binding ability. It was suggested that both RspA and RspB were exposed on the cell surface of E. rhusiopathiae, as were the bacterial cells agglutinated by the anti-RspA immunoglobulin G (IgG) and anti-RspB IgG. RspA and RspB were present both in surface-antigen extracts and the culture supernatants of E. rhusiopathiae Fujisawa-SmR (serovar 1a) and SE-9 (serovar 2). The recombinant RspA, but not RspB, elicited protection in mice against experimental challenge. These results suggest that RspA and RspB participate in initiation of biofilm formation through their binding abilities to abiotic and biotic surfaces.

CloningSerratia entomophilaAntifeeding Genes—a Putative Defective Prophage Active against the Grass GrubCostelytra zealandica

“…Protein repeat motifs have been identified in many virulence-related proteins of gram-positive bacteria, where they have been found to function as ligands to various host receptors or to have specific affinity for cellular components (36,41). Although the role of the Afp13 repeat structure has yet to be elucidated, it is not believed to be a virulence factor by itself.…”

Binding of Lymphoid Chemokines to Collagen IV That Accumulates in the Basal Lamina of High Endothelial Venules: Its Implications in Lymphocyte Trafficking

“…In addition, the fact that CCL5 has two BBXB motifs that bind to GAGs (30) but fail to bind Col IV indicates that electrostatic interactions alone are not sufficient for chemokines to bind Col IV. Given that Col IV can interact with a variety of structurally different proteins, including ECM components (31,32), growth factors (33,34), proteinases (35,36), and bacterial proteins (37,38), multiple mechanisms are probably used to bind these molecules. Detailed structural analyses will be needed to understand the precise mechanisms underlying the selective binding by Col IV of lymphoid chemokines.…”

Complete Genome Sequence ofRickettsia typhiand Comparison with Sequences of Other Rickettsiae

“…Although no function of the Sca proteins was demonstrated, it was suggested that some autotransporters have adhesion or protease activities and could play a role in rickettsial virulence (38,69). A characteristic of bacterial adhesins that bind to eukaryotic extracellular matrix proteins is the presence of amino acid repeats (57). A 50-residue repeat occurs six times within the carboxy-terminal portion of the Sca2 passenger domain, suggesting that this protein may be involved in binding of R. typhi to host cells.…”