Query: NC_016809:389561 Haemophilus influenzae 10810, complete genome
Lineage: Haemophilus influenzae; Haemophilus; Pasteurellaceae; Pasteurellales; Proteobacteria; Bacteria
General Information: A group of organisms that are either obligate parasites or commensal organisms found in animal mucous membranes. Almost all species require the presence of important growth factors found in the blood of their hosts, including either X factor (protoporphyrin IX or heme) or V factor (nicotinamide adenine dinucleotide (NAD or NADP)). This organism was first isolated in the 1890s during an influenza pandemic by Pfeiffer, and was originally thought to be the source of influenza, although later it was shown to be a secondary pathogen and may be synergistic with the influenza virus. This bacterium is one of the leading causes of meningitis in young children, and it may also cause septicemia, otitis media (inflammation of the middle ear), sinusitis (inflammation of the sinus cavity) and chronic bronchitis. It is highly adapted to its human host and typically lives in the nasopharynx and is a major cause of lower respiratory infections in infants and small children in developing countries (type 1b strain), although vaccine use has resulted in the decline of infections. The encapsulated organism can penetrate the blood and avoid both phagocytosis and complement-mediated lysis. All known strains produce neuraminidase and an IgA protease as well as fimbrial adhesins for attachment.
Subject: NC_004668:1010610 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.