IN, CV and AG conceived of the study, and participated in its GDC-973 design and coordination and helped to draft the manuscript. All authors read and approved the final manuscript.”
“Background Bacterial adhesive proteins, proteinaceous adhesins, are frequently the Idasanutlin most critical factor at the onset of a bacterial infection [1–3]. The identification and characterization of such adhesins at the molecular level is therefore crucial for the detailed understanding of bacterial pathogenesis, for the design of vaccines and for the development of novel antibacterial drugs [4,

5]. Although some bacterial adhesins have successfully been produced on a large scale and described in detail (for examples the reader is referred to recent reviews and original publications [1–3]), this type of molecules are often difficult to express by conventional techniques or they possess a complicated structure [6]. This has in many cases hampered further characterization of bacterial adhesins and various surface display techniques and alternative expression methods have been developed for the analysis of adhesive polypeptides. However, commonly used surface display techniques suffer from the drawback that they rely on the attachment of the gene product of interest to the surface of the carrier, for example the phage [7], the see more bacterium [8, 9], or the ribosome [10],

which may compromise correct folding of the polypeptide of interest. Reports on high-level extracellular secretion of heterologous proteins in Gram-negative bacteria are scarce and these expression techniques are currently a field of active research [11, 12]. The adhesion of the important and highly versatile human pathogenic bacterium Staphylococcus aureus to host surfaces is mediated by a RVX-208 range of adhesins, some of which are very well characterized [13]. The majority of S. aureus adhesins belong to the group of microbial surface components recognizing adhesive matrix molecules, MSCRAMMs [3, 14], whereas others represent secretable expanded repertoire adhesive molecules [15]. Some of the known S. aureus adhesins have been identified

by phage display based on staphylococcal genomic libraries, a technique also used for identification of secreted proteins of the bacterium [16–19]. Bacterial surface display and ribosome display have been exploited for the mapping of S. aureus epitopes recognized by human antibodies and for the identification of peptide motifs that mediate entry into eukaryotic cells [20–22]. Nevertheless, on the basis of genomics and proteomics data, a number of surface proteins and approximately 1000 proteins of unknown function in the proteome of S. aureus remain to be characterized [13, 23] and among these also lie putative novel adhesins. We recently described an efficient technique for the secretion of foreign proteins into the growth medium of a secretion-competent derivative of the Escherichia coli K12-strain called MKS12 [24].