Gram Negative Bacteria

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The purpose of the unknown experiment is to understand and identify a gram positive and a gram negative. Bacteria can be very helpful in clinical uses and many pharmaceutical drugs are based on the organism. Knowing how a bacterium works and how it is structured can be crucial to determine how it affects each individual. Several biochemical tests were performing to separate and determine the identities of the microorganisms. Broth tube number 31 containing unknown microorganisms. One of the microorganisms is gram positive which can be separate from the gram negative using the four-way streak isolation from the lab manual. The purpose of the streak isolation is to obtain single colonies on a Columbia CNA agar plate. C-CNA agar is a type of …show more content…
E. aerogenes is a non-spore forming organism with 1.2-3 μm in length by 0.6-1 μm in diameter and belong to the Enterobacteriaceae Family. E. aerogenes have capsule with flagella which enable them to be motile. They are facultative anaerobes which mean they are able to survive with or without the presence of oxygen. The optimum growth temperature is range from 30oC to 37oC which classify as a mesophile. It is commonly associated E. aerogenes with nosocomial infection and they are acknowledged as opportunistic pathogens. Several infections cause by E. aerogenes including cerebral abscess, pneumonia, meningitis, and UTI. E. aerogenes can be found in many different places such as the intestines of humans and animals, sewage, and dairy products. They can be transmitting from cross-infection such as contaminated hands to sterile body areas, insertion of medical devices, and during surgical operations. Infections can also transmit through fecal-oral route from person to person. Vaccines aren’t available, but antibiotics have been shown to be affective to treat E. aerogenes (Enterobacter, 2011). Since 2010, E. aerogenes has been considered to be the fifth highest Enterobacteriaceae culprit for nosocomial infections in France (Davin-Regli,

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