Search results
Results from the WOW.Com Content Network
Bacterial taxonomy is the classification of strains within the domain Bacteria into hierarchies of similarity. This classification is similar to that of plants , mammals , and other taxonomies. However, biologists specializing in different areas have developed differing taxonomic conventions over time.
Pathogenic bacteria are bacteria that can cause disease. [1] This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and many are beneficial but others can cause infectious diseases. The number of these pathogenic species in humans is estimated to be fewer than a hundred. [2]
Escherichia coli is one of the most diverse bacterial species, with several pathogenic strains with different symptoms and with only 20% of the genome common to all strains. [1] Furthermore, from the evolutionary point of view, the members of genus Shigella ( dysenteriae , flexneri , boydii , sonnei ) are actually E. coli strains "in disguise ...
E. coli and related bacteria constitute about 0.1% of gut flora, [4] and fecal–oral transmission is the major route through which pathogenic strains of the bacterium cause disease. Cells are able to survive outside the body for only a limited amount of time, which makes them ideal indicator organisms to test environmental samples for fecal ...
A strain is a genetic variant or subtype of a microorganism (e.g., a virus, bacterium or fungus). For example, a "flu strain" is a certain biological form of the influenza or "flu" virus. These flu strains are characterized by their differing isoforms of surface proteins.
Veillonella dispar is the most nitrate-reducing bacterium in the oral cavity, which is beneficially anti-bacterial. [2] When Veillonella is responsible for clinical infections in humans, it should be kept in mind that more than 70% of the strains are resistant to penicillin, while more than 95% of the strains are susceptible to amoxicillin ...
E. meningoseptica is positive by the catalase test, the oxidase test, and the indole test. It is negative by the urease test. In general, it is negative by the nitrate reductase test, although some strains are positive. [6] E. meningoseptica grows well on blood agar and chocolate agar. Colonies are very pale yellow and may not be easily evident ...
A serotype or serovar is a distinct variation within a species of bacteria or virus or among immune cells of different individuals. These microorganisms , viruses, or cells are classified together based on their shared reactivity between their surface antigens and a particular antiserum , allowing the classification of organisms to a level ...