What is "erysipelothrix"

Erysipelothrix \Er`y*sip"e*lo*thrix\ ([e^]r`[i^]*s[i^]p"[-e]*las), n. [see erysipelas.] (Microbiol.) a genus of non-motile, rod-shaped Gram-positive bacteria of the family Corynebacteriaceae. They are facultatively anaerobic and produce acid but no gas from glucose. Members of this genus are parasitic on fish, birds, and mammals, including man. The type species of the genus, Erysipelothrix rhusiopathiae, causes erysipeloid in man.
--Stedman

Erysipelothrix is a genus of bacteria containing three species. "The hallmark of Erysipelothrix is the presence of a type B cell wall, in which the peptide bridge is formed between amino acids at positions 2 and 4 of adjacent peptide side-chains and not, as in the vast majority of bacteria, between amino acids at positions 3 and 4."

The best known species is Erysipelothrix rhusiopathiae, which causes erysipelas of swine and other animal diseases. The other two species are apparently not pathogenic. Erysipelothrix tonsillarum was described in 1987. Erysipelothrix inopinata was described in 2004. These two species have been isolated from the tonsils of healthy pigs. The new family Erysipelotrichidae was erected to contain this genus.

These bacteria are Gram-positive. They can be mistaken for Gram-negative bacteria during analysis because they lose their staining easily. They are not acid-fast. They are slender, nonmotile rod-shaped bacteria. They are straight or slightly curved and can appear long and filamentous. They exist singly, in V-shaped pairs, or in short chains. They are aerobic to facultatively anaerobic.