PubMed 53. Pfaffl MW: A new mathematical model for relative quantification in real-time RT-PCR. Nucleic Acids Res 2001, 29:e45.PubMedCrossRef Authors’ contributions RFT and ECM performed and designed experiments, and interpreted data. TFK designed experiments and interpreted the data. PWOT designed experiments, analyzed data and co-wrote the manuscript. JCC conceived the study, designed the experiments, interpreted the data and co-wrote the manuscript. All authors read and approved the final manuscript.”
“Background

Gram-negative proteobacteria deploy various types of protein secretion systems for exporting selected sets of proteins to the cell surface, the extracellular space or into host cells [1, 2]. Type III Secretion Systems (T3SS) are directly related to pathogenicity ATR inhibitor or to symbiosis with higher organisms and constitute essential mediators of the interactions between gram-negative bacterial cells

and eukaryotic ones [3–8] as the T3SS efficiently translocates bacterial proteins (effectors) directly into the host cell cytoplasm when fully developed. The T3SS apparatus comprises three distinct parts: a) the basal body, which forms a cylindrical base that penetrates the two bacterial membranes and the periplasmic space; b) the extracellular part with the needle or the pilus as its main feature which is formed through the polymerization of specialized protein subunits that are T3SS substrates themselves; and c) the cytoplasmic VE-822 datasheet part, which forms the export gate for

secretion control. This apparatus is built by specific core proteins encoded by a conserved subset of genes tightly organized in gene clusters with counterparts in the bacterial flagellum [6, 7]. Phylogenetic analyses of click here the core T3SS proteins revealed that the T3S systems evolved into seven distinct families that spread between bacteria by horizontal gene transfer. (1) The Ysc-T3SS family, named after the archetypal Yersinia system, is present in α-, β-, γ-, and δ- proteobacteria. At least in α-proteobacteria the system confers resistance to phagocytosis and triggers macrophage apoptosis. (2) The Ssa-Esc-T3SS family is named after the archetypal T3SS of enteropathogenic and enterohemorrhagic E.coli. (3) The Inv-Mxi-Spa-T3SS family named after the Inv-Spa system of Salmonella enterica and the Inv-Mxi T3S system of Shigella spp. The family members trigger bacterial uptake by nonphagocytic cells.(4) The Hrc-Hrp1- and (5) the Hrc-Hrp2-T3SS families are present in plant pathogenic bacteria of the genus Pseudomonas, SN-38 Erwinia, Ralstonia and Xanthomonas. The two families are differentiated on the basis of their genetic loci organization and regulatory systems. (6) The Rhizobiales-T3SS family (hereafter referred to as Rhc-T3SS) is dedicated to the intimate endosymbiosis serving nitrogen fixation in the roots of leguminous plants. (7) Finally the Chlamydiales-T3SS is present only in these strictly intracellular nonproteobacteria pathogens [8, 9].