The family Enterobacteriaceae is a large family of Gram-negative bacteria. It was first proposed by Rahn in 1936, and now includes over 50 genera and more than 200 species. Its classification above the level of family is still a subject of debate, but one classification places it in the order Enterobacteriales of the class Gammaproteobacteria in the phylum Proteobacteria.
Enterobacteriaceae includes, along with many harmless symbionts, many of the more familiar pathogens, such as Salmonella, Escherichia coli, Yersinia pestis, Klebsiella, and Shigella. Other disease-causing bacteria in this family include Proteus, Cronobacter, Serratia, and Citrobacter. Phylogenetically, in the Enterobacteriales, several peptidoglycan-less insect endosymbionts form a sister clade to the Enterobacteriaceae, but as they are not validly described, this group is not officially a taxon; examples of these species are Sodalis, Buchnera, Wigglesworthia, Baumannia cicadellinicola, and Blochmannia, but not former members of Rickettsia. Members of the Enterobacteriaceae can be trivially referred to as enterobacteria or “enteric bacteria”, as several members live in the intestines of animals. In fact, the etymology of the family is enterobacterium with the suffix to designate a family (aceae)—not after the genus Enterobacter (which would be “Enterobacteraceae”)—and the type genus is Escherichia.
In Regulation (EC) 2073/2005, the European Commission states that Salmonella and Cronobacter (Enterobacter sakazakii) are the microorganisms of greatest concern in infant formula, formula for special medical purposes and follow-on formula. The lethality rate caused by neonatal Cronobacter infections is between 40-80%. Enterobacteriaceae, which are more often present, may be used as a risk indicator. The foodproof® Enterobacteriaceae plus Cronobacter Detection Kit is based on the real-time PCR technology, which is well-established in the food industry. The kit enables the detection of Enterobacteriaceae and identification of Cronobacter in one single assay. Save time and cost: negative for Enterobacteriaceae means negative for Salmonella, too!