Query: NC_006368:3211998 Legionella pneumophila str. Paris, complete genome
Lineage: Legionella pneumophila; Legionella; Legionellaceae; Legionellales; Proteobacteria; Bacteria
General Information: This serogroup I strain is endemic in France. Causes Legionnaire's disease. This organism is a non-marine bacterium usually found growing inside other organisms such as protozoans in aquatic environments. They can also be found in soil, freshwater, and in biofilms. The first outbreak of Legionnaire's disease occurred in 1976 at an American Legion convention and the resulting pneumonia-like disease resulted in 34 deaths. The cause of the disease was traced to Legionella bacteria. Once the bacteria are brought into the lungs they make contact with alveolar macrophages and are internalized where they can cause severe respiratory distress. Internalization occurs through specialized vacuoles (replicative phagosomes) that allow the bacteria to grow and replicate prior to escape from the macrophage. Formation of the replicative phagosome, which requires reprogramming of the normal phagosome maturation pathway, requires a type IV secretion system called the Dot/Icm system. This type IV system is closely related to the conjugative system of plasmid ColIb-P9, and is involved in the secretion of numerous protein components that aid in formation of the replicative phagosome. Other virulence determinants include a set of multidrug transporters and other efflux pumps for toxic compounds that may allow the organism to persist in its habitat, a set of LPS phase variable genes that enhance immune evasion, and a type II secretion system for transport of hydrolases.
Subject: NC_011080:4703266 Salmonella enterica subsp. enterica serovar Newport str. SL254,
Lineage: Salmonella enterica; Salmonella; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria
General Information: The SL254 strain is an MDR strain from one of two distinct lineages of the Newport serovar. Salmonella enterica subsp. enterica serovar Newport is common worldwide. Outbreak investigations and targeted studies have identified dairy cattle as the main reservoir this serotype. Antimicrobial resistance (Newport MDR-AmpC) is particularly problematic in this serotype, and the prevalence of Newport MDR-AmpC isolates from humans in the United States has increased from 0% during 1996-1997 to 26% in 2001. MDR strains have been recorded as resistant to ampicillin, chloramphenicol, streptomycin, sulphonamides and tetracycline (ACSSuT) and many of these strains show intermediate or full resistance to third-generation cephalosporins, kanamycin, potentiated sulphonamides, and gentamicin. This group of Enterobactericiae have pathogenic characteristics and are one of the most common causes of enteric infections (food poisoning) worldwide. They were named after the scientist Dr. Daniel Salmon who isolated the first organism, Salmonella choleraesuis, from the intestine of a pig. The presence of several pathogenicity islands (PAIs) that encode various virulence factors allows Salmonella spp. to colonize and infect host organisms. There are two important PAIs, Salmonella pathogenicity island 1 and 2 (SPI-1 and SPI-2) that encode two different type III secretion systems for the delivery of effector molecules into the host cell that result in internalization of the bacteria which then leads to systemic spread.