Enterobacteriaceae is a large family of Gram-negative bacteria. It was first proposed by Rahn in 1936, and now includes over 30 genera and more than 100 species. Its classification above the level of family is still a subject of debate, but one classification places it in the order Enterobacterales of the class Gammaproteobacteria in the phylum Proteobacteria. In 2016, the description and members of this family were emended based on comparative genomic analyses by Adeolu et al.
Klebsiella pneumoniae is a Gram-negative, non-motile, encapsulated, lactose-fermenting, facultative anaerobic, rod-shaped bacterium. It appears as a mucoid lactose fermenter on MacConkey agar.
The Chlamydiae are a bacterial phylum and class whose members are remarkably diverse, including pathogens of humans and animals, symbionts of ubiquitous protozoa, and marine sediment forms not yet well understood. All of the Chlamydiae that humans have known about for many decades are obligate intracellular bacteria; in 2020 many additional Chlamydiae were discovered in ocean-floor environments, and it is not yet known whether they all have hosts. Historically it was believed that all Chlamydiae had a peptidoglycan-free cell wall, but studies in the 2010s demonstrated a detectable presence of peptidoglycan, as well as other important proteins.
Klebsiella is a genus of Gram-negative, oxidase-negative, rod-shaped bacteria with a prominent polysaccharide-based capsule.
The Burkholderiaceae are a family of bacteria included in the order Burkholderiales. It includes some pathogenic species, such as Burkholderia mallei (glanders) and Burkholderia pseudomallei (melioidosis).
Eggerthella is a bacterial genus of Actinobacteria, in the family Coriobacteriaceae. Members of this genus are anaerobic, non-sporulating, non-motile, Gram-positive bacilli that grow singly, as pairs, or in short chains. They are found in the human colon and feces and have been implicated as a cause of ulcerative colitis, liver and anal abscesses and systemic bacteremia.
Alphaproteobacteria is a class of bacteria in the phylum Proteobacteria. Its members are highly diverse and possess few commonalities, but nevertheless share a common ancestor. Like all Proteobacteria, its members are gram-negative and some of its intracellular parasitic members lack peptidoglycan and are consequently gram variable.
Sphingobacteriaceae is a family of environmental bacteria.
Ensifer is a genus of nitrogen-fixing bacteria (rhizobia), three of which have been sequenced.
Raoultella planticola is a Gram-negative bacterium of the genus Raoultella. R. planticola is quite similar in appearance to Klebsiella pneumoniae and must be identified based on growth habits or DNA analysis. A number of strains have been identified. R. planticola has been determined to have complicated at least one case of severe pancreatitis.
Acetomicrobium is a genus in the phylum Synergistetes (Bacteria). In 2016, the former genus Anaerobaculum was folded into Acetomicrobium.
Actinocatenispora is a genus in the phylum Actinobacteria (Bacteria).
Algoriphagus is a genus in the phylum Bacteroidetes (Bacteria).
Raoultella terrigena is a Gram-negative bacterial species of the genus Raoultella, previously classified in the genus Klebsiella. It has primarily been isolated from soil and water samples, but rarely from humans. Studies have estimated fewer than 1% of healthy people harbor this species. This species has shown no connection with disease in humans despite expressing many of the virulence factors expressed by other Klebsiella species such as Klebsiella pneumoniae.
Neomegalonema is a genus of bacteria. Up to now there is only one species of this genus known.
Neomegalonema perideroedes is a filamentous bacterium from the genus of Neomegalonema which has been isolated from activated bulking sludge from industrial wastewater in Grindsted in Denmark.
Erythrobacteraceae is a bacterium family in the order of Sphingomonadales.
Coprothermobacterota is a newly proposed phylum of nonmotile, rod-shaped bacteria.
Klebsiella huaxiensis is a pathogenic gram-negative bacterium in the family Enterobacteriaceae. It is gas-producing, non-motile, and does not form spores.
Komagataeibacter is a genus of bacteria in the family Acetobacteraceae. It was described in 2012 by Yamada et al. The type species is Komagataeibacter xylinus.
