Query: NC_015760:8914 Streptococcus salivarius CCHSS3, complete genome
Lineage: Streptococcus salivarius; Streptococcus; Streptococcaceae; Lactobacillales; Firmicutes; Bacteria
General Information: The commensal bacterium Streptococcus salivarius is predominant specie of the human oropharyngeal tract and exerts an important role in oral ecology. Streptococcus salivarius is an aerobic, gram-positive coccus. This organism is the most common organism isolated from the human oral cavity. Streptococcus salivarius can also be an opportunistic pathogen causing endocarditis, blood infection, and peritonitis. Streptococci are Gram-positive, nonmotile, nonsporeforming, catalase-negative cocci that occur in pairs or chains. Members of this genus vary widely in pathogenic potential. Most streptococci are facultative anaerobes, and some are obligate anaerobes.
Subject: NC_004668:3156247 Enterococcus faecalis V583, complete genome
Lineage: Enterococcus faecalis; Enterococcus; Enterococcaceae; Lactobacillales; Firmicutes; Bacteria
General Information: This strain is one of the first vancomycin-resistant strains isolated. This isolate came from a blood culture derived from a chronically-infected patient in 1987 from Barnes Hospital in St. Louis, Missouri, USA. This strain was found to lack the cytolysin gene and a surface adhesin, Esp, that contributes to urinary tract infections. Mobile genetic elements make up one quarter of the genome. 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 can cause urinary tract infections, bacteremia (bacteria in the blood), and infective endocarditis (inflammation of the membrane surrounding the heart), similar to infections caused by Enterococcus faecium. Hospital-acquired infections from this organism are on the rise due to the emergence of antiobiotic resistance strains. Enterococcus faecalis produces a cytolysin toxin that is encoded on various mobile genetic elements, pathogenicity islands, and conjugative plasmids. The cytolysin aids in pathogenesis, possibly by causing destruction of cells such as erythrocytes, which allows access to new nutrients for the organism.