Query: NC_020207:2240115 Enterococcus faecium NRRL B-2354, complete genome
Lineage: Enterococcus faecium; Enterococcus; Enterococcaceae; Lactobacillales; Firmicutes; Bacteria
General Information: This genera consists of organisms typically found in the intestines of mammals, although through fecal contamination they can appear in sewage, soil, and water. They cause a number of infections that are becoming increasingly a problem due to the number of antibiotic resistance mechanisms these organisms have picked up. Both Enterococcus faecalis and Enterococcus faecium cause similar diseases in humans, and are mainly distinguished by their metabolic capabilities. This opportunistic pathogen causes a range of infections similar to those observed with Enterococcus faecalis, including urinary tract infections, bacteremia (bacteria in the blood), and infective endocarditis (inflammation of the membrane surrounding the heart). Hospital-acquired infections from this organism are on the rise due to the emergence of antiobiotic resistance strains and has led to the rise of vancomycin-resistant Staphylococcus aureus strains due to the horizontal transfer of Enterococcus antibiotic resistance genes. Little is known about the virulence mechanisms in this organism, but the genome does encode an esp gene for the surface adhesin. Vancomycin resistant isolates are more typically Enterococcus faecium than Enterococcus faecalis.
Subject: NC_005945:5202176 Bacillus anthracis str. Sterne, complete genome
Lineage: Bacillus anthracis; Bacillus; Bacillaceae; Bacillales; Firmicutes; Bacteria
General Information: This strain carries the anthrax toxin plasmid pXO1 but not the capsule plasmid pXO2 and is therefore avirulent but toxigenic. It is the counterpart to the Pasteur strain that carries pXO2 but not pXO1. This strain is often used for vaccine development. Under starvation conditions this group of bacteria initiate a pathway that leads to endospore formation, a process that is thoroughly studied and is a model system for prokaryotic development and differentiation. Spores are highly resistant to heat, cold, dessication, radiation, and disinfectants, and enable the organism to persist in otherwise inhospitable environments. Under more inviting conditions the spores germinate to produce vegetative cells. This organism was the first to be shown to cause disease by Dr. Louis Pasteur (the organism, isolated from sick animals, was grown in the laboratory and then used to infect healthy animals and make them sick). This organism was also the first for which an attenuated strain was developed as a vaccine. Herbivorous animals become infected with the organism when they ingest spores from the soil whereas humans become infected when they come into contact with a contaminated animal. PA/LF and PA/EF complexes are internalized by host cells where the LF (metalloprotease) and EF (calmodulin-dependent adenylate cyclase) components act. At high levels LF induces cell death and release of the bacterium while EF increases host susceptibility to infection and promotes fluid accumulation in the cells.