Enterobacteriales
(more information below)
Gammaproteobacteria
Facultatively anaerobic, gram-negative rods
Peritrichously flagellated if motile
Inhabit the intestinal tracts of humans and other animals
Fimbriae that help them to adhere to surfaces or mucous membranes
Sex pili for reproduction: help to transfer bacteria resistance
Produce bacteriocins that cause the lysis of related bacteria, which may help maintain the ecological balance in the intestines