Erysipelothrix
A Microbial Biorealm page on the genus Erysipelothrix
Classification
Higher order taxa
Bacteria; Firmicutes; Mollicutes; Anaeroplasmatales; Erysipelotrichidae; Erysipelothrix
Species
Erysipelothrix rhusiopathiae, Erysipelothrix tonsillarum, Erysipelothrix inopinata
Description and significance
Erysipelothrix are pathogenic bacteria that infect over 50 animal species, specifically domesticated pigs. There are three species: Erysipelothrix rhusiopathiae, E. Tonsillarum, and E. inopinata, each of which varies in its virulence between its two different strains. The smooth strain of each species is pathogenic, while the rough is not. Erysipelothrix rhusiopathiae was first isolated by Koch in 1876. This was the only known species until a subsequent species was discovered in the tonsils of apparently healthy pigs. This new species was named E. Tonsillarum. The third species, Erysipelothrix inopinata was first isolated in the course of sterile filtration of vegetable peptone broth.
Genome structure
The USDA Microbial Genomics Stakeholder Workshop for Animal Health and Food Safety Pathogens considered sequencing Erysipelothrix rhusiopathiae as a swine pathogen. Sequence results are pending.
Cell structure and metabolism
Erysipelothrix is a chemoorganotrophic facultative anaerobe with a respiratory metabolism; it is weakly fermentative. Erysipelothrix is gram positive but may appear gram negative because it decolorizes easily. Cells are catalase-negative and oxidase negative. Erysipelothrix is non-encapsulated, nonsporulating and nonmotile. Its slender rods have rounded ends and are straight or slightly curved, but tend to form long filaments. Its cell wall is what helps to differentiate these bacteria from others with a B-cell wall type in which the peptide bridge is formed between amino acids at positions 2 and 4 of adjacent peptide side chains. This distinguishes Erysipelothrix from other bacteria because most others have the peptide bridge formed between amino acids at positions 3 and 4. Colonies of these bacteria have two distinct forms which include the smooth and a larger round form. The smooth is about .1mm in diameter, convex and circular. The rough form is about .2-.4 mm in diameter, flat with a matte surface. Organisms are either arranged in single short chains, in pairs in a "V" configuration or are grouped randomly. The exact growth requirements of the organism have not yet been determined. However, several amino acids, riboflavin, and small amounts of oleic acid are required, and growth is enhanced by tryptophan. Growth occurs at an optimal temperature of 30-37°C and a pH of 7.2-7.6 and is improved by 5-10% carbon dioxide.
Ecology
Erysipelothrix rhusiopathiae can be found in sewage, the guts of fish and ground contaminated with animal feces. These bacteria are unable to survive for a long period of time in external environments since the rough form prefers slightly acidic conditions at 37oC and the smooth prefers a slightly alkaline environment at 30oC.
Pathology
How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.
Current Research
Enter summarries of the most rescent research here--at least three required
References
Edited by student of Dr. Kirk Bartholomew
