Citation for published version: Pullinger, GD, Paulin, SM, Charleston, B, Watson, PR, Bowen, AJ, Dziva, F, Morgan, E, Villarreal-Ramos, B, Wallis, TS & Stevens, MP 2007, 'Systemic translocation of Salmonella enterica serovar Dublin in cattle occurs predominantly via efferent lymphatics in a cell-free niche and requires type III secretion system I (T3SS-1) but not T3SS-2' Infection and Immunity,...

Gram-negative bacteria secrete proteins using a type III secretion system (T3SS), which functions as a needle-like molecular machine. The many proteins involved in T3SS construction are tightly regulated due to its role in pathogenesis and motility. Here, starting with the 35 kb Salmonella pathogenicity island 1 (SPI-1), we eliminated internal regulation and simplified the genetics by removing ...

Translocating proteins across the double membrane of Gram-negative bacteria, type III secretion systems (T3SS) occur in two evolutionarily related forms: injectisomes, delivering virulence factors into host cells, and the flagellar system, secreting the polymeric filament used for motility. While both systems share related elements of a cytoplasmic sorting platform that facilitates the hierarch...

Pseudomonas syringae translocates virulence effector proteins into plant cells via a type III secretion system (T3SS) encoded by hrp (for hypersensitive response and pathogenicity) genes. Three genes coregulated with the Hrp T3SS system in P. syringae pv. tomato DC3000 have predicted lytic transglycosylase domains: PSPTO1378 (here designated hrpH), PSPTO2678 (hopP1), and PSPTO852 (hopAJ1). hrpH...

Acquisition of a single copy, large virulence plasmid, pINV, led to the emergence of Shigella spp. from Escherichia coli. The plasmid encodes a Type III secretion system (T3SS) on a 30 kb pathogenicity island (PAI), and is maintained in a bacterial population through a series of toxin:antitoxin (TA) systems which mediate post-segregational killing (PSK). The T3SS imposes a significant cost on t...

Microarray analysis of Pseudomonas aeruginosa mRNA transcripts expressed in vivo during animal infection has not been previously used to investigate potential virulence factors needed in this setting. We compared mRNA expression in bacterial cells recovered from the gastrointestinal (GI) tracts of P. aeruginosa-colonized mice to that of P. aeruginosa in the drinking water used to colonize the m...

Herein we describe a pathogenic role for the Pseudomonas aeruginosa type three secretion system (T3SS) needle tip complex protein, PcrV, in causing lung endothelial injury. We first established a model in which P. aeruginosa wild type strain PA103 caused pneumonia-induced sepsis and distal organ dysfunction. Interestingly, a PA103 derivative strain lacking its two known secreted effectors, ExoU...

The prevailing paradigm of Salmonella enteropathogenesis based on monolayers asserts that Salmonella pathogenicity island-1 Type Three Secretion System (SPI-1 T3SS) is required for bacterial invasion into intestinal epithelium. However, little is known about the role of SPI-1 in mediating gastrointestinal disease in humans. Recently, SPI-1 deficient nontyphoidal Salmonella strains were isolated...

A steep oxygen gradient within the mucus of the cystic fibrosis (CF) lung combined with the biofilm mode of bacterial growth forces respiratory pathogens to adapt to varying oxygen availability. This study presents the novel finding that the Pseudomonas aeruginosa response to limiting oxygen stress includes induction of its type III secretion system (T3SS), which subsequently contributes toward...