see text The Enterobacteriaceae are a large family of bacteria, including many of the more familiar pathogens, such as Salmonella and Escherichia coli. Genetic studies place them among the Proteobacteria, and they are given their own order (Enterobacteriales), though this is sometimes taken to include some related environmental samples.

Members of the Enterobacteriaceae are rod-shaped, and are typically 1-5 μm in length. They are facultative anaerobes, producing energy through fermentation of sugars, producing lactic acid and various other end products. They also reduce nitrate to nitrite. Like all proteobacteria, they have Gram-negative stains, and can be distinguished from similar bacteria by the absence of oxidase. Most have many flagella used to move about, but a few genera are non-motile.

Many members are a normal part of the flora found in the intestines of humans and other animals, while others are found in water or soil, or are parasites on a variety of different animals and plants. Escherichia coli, better known as E. coli, is one of the most important model organisms and its genetics and biochemistry have been closely studied!

The following genera are included here:

• Alishewanella
• Alterococcus
• Aquamonas
• Aranicola
• Arsenophonus
• Azotivirga
• Candidatus Blochmannia
• Brenneria
• Buchnera
• Budvicia
• Buttiauxella
• Cedecea
• Citrobacter
• Dickeya
• Edwardsiella
• Enterobacter
• Erwinia, e.g. Erwinia amylovora
• Escherichia, e.g. Escherichia coli
• Ewingella
• Grimontella
• Hafnia
• Klebsiella, e.g. Klebsiella pneumoniae
• Kluyvera
• Leclercia
• Leminorella
• Moellerella
• Morganella
• Obesumbacterium
• Pantoea
• Pectobacterium
• Candidatus Phlomobacter
• Photorhabdus
• Plesiomonas, e.g. Plesiomonas shigelloides
• Pragia
• Proteus, e.g. Proteus vulgaris
• Providencia
• Rahnella
• Raoultella
• Salmonella
• Samsonia
• Serratia, e.g. Serratia marcescens
• Shigella
• Sodalis
• Tatumella
• Trabulsiella
• Wigglesworthia
• Xenorhabdus
• Yersinia, e.g. Yersinia pestis
• Yokenella