In search of Brucella abortus type IV secretion substrates: screening and identification of four proteins translocated into host cells through VirB system

摘要: Type IV secretion systems (T4SS) are specialized protein complexes used by many bacterial pathogens for the delivery of effector molecules that subvert varied host cellular processes. Brucella spp. facultative intracellular capable survival and replication inside mammalian cells. T4SS (VirB) is essential to lysosome fusion create an organelle permissive replication. One possible role VirB translocate proteins modulate functions biogenesis replicative organelle. We hypothesized with eukaryotic domains or protein-protein interaction domains, among others, would be good candidates modulation cell functions. To identify these candidates, we performed in silico screen looking distinctive features. Translocation 84 potential substrates was assayed using adenylate cyclase reporter. By this approach, identified six delivered cytoplasm upon infection macrophage-like cells could determine four them, encoded genes BAB1_1043, BAB1_2005, BAB1_1275 BAB2_0123, require a functional their delivery. confirmed VirB-mediated translocation one immunofluorescence confocal microscopy, found N-terminal 25 amino acids required its into