Enterobacteriaceae Family Essay

The Enterobacteriaceae family is a group of microorganisms classed by their unique collection of characteristics. This family of microorganisms includes: Proteus species, Escherichia, Klebsiella, Enterobacter, and Serratia species. Over many years developments have been made in relation to the different genera within Enterobacteriaceae. Such developments have led to the establishment of a range media and methodologies for the investigation into the species by their characteistics. Enterobacteriaceae are characterised as Gram-negative, non-spore-forming bacteria. They are facultative anaerobes which of the ability to reduce nitrate to nitrite, with the exception of some strains of Yersinia and Erwinia which are Saccharobacter fermentans. These microorganisms are motile by peritrichous flagella with the exception to Shigella and Tatumella among other members. Poretus spp. and Salmonella spp. are example of motile microorganisms within the family however, containing their own exceptions (Gus Gonzalez, MD. Et al. 2014)

1.2 Characteristics traits and the associated test for their detection.

Common trait amongst the Enterobacteriaceae family, used for their differentiation from other closely related bacteria, is that they lack cytochrome C oxidase. Thus meaning that they are oxidase negative.

Mac conkey media is both a selective and differential media used for the detection and isolation of enteric gram negative bacteria i.e. members of the Enterobacteriaceae family and pseudomonas spp.. The media is based on the bile salt-neutral red-lactose agar. The growth of gram-positive bacteria is inhibited on this media by Crystal violet and bile salts. Bile salts are tolerated by enteric gram-negative by the passion of a bile resistant outer membrane. Mac Conkey media is selective for Gram-negatives and differential between lactose and non-lactose fermenting gram negative