| Citrobacter, Escherichia hermannii, Ewingella americana, Citrobacter koseri|Citrobacter sedlakii Wikipedia
Citrobacter sedlakii is a Gram-negative, oxidase-negative species of bacillus. It is known to be one of the species which produces the Escherichia coli O157:H7 antigen. The species was described by Brenner et al. along with 10 other Citrobacter species in 1993. C. sedlakii exists as a commensal gut organism in humans and animals.