Citrobacter freundii - Lab Report Example

The biosphere is characterized by the presence of microorganisms allover which invariably impacts on the environment they are growing. Microorganisms are present in the air, soil, plants and animals and their presence can be harmful, beneficial or inapparent with respect to human measure. Pathogenic microorganisms are known to cause diseases to the host animal while opportunistic microorganisms stay in a healthy host for longer period without causing illness the immune system of the host is suppressed.

However some microorganisms are very beneficial as they are used in biotechnological processes, soil and to degrade waste. This paper focuses on experiment for isolation and identification of Citrobacter freundii bacterium. The bacterium Citrobacter freundii is an opportunistic pathogen belonging to the family of Enterobacteriaceae and was first identified by Gillen and Werkman in 1932 from soil extracts (Leboffe & Pierce, 2011). It is a long rod shaped facultative anaerobic gram-negative bacilli bacterium characterized by many long flagella to aid its movement though others are none motile. C. freundii is rod shaped between 1um diameter and 2-6um in length with optimum growth temperature of 370C and produces gas and acid as a result of carbohydrate catabolism (MicrobeWiki, 2011).

The habitat for Citrobacter freundii includes food, water, soil, sewage and the intestinal tracts of both human and animals (MicrobeWiki, 2011). The diverse habitat upon which this bacterium can grow is mainly due to its ability to metabolize citrate and lactose as the main sources of carbon. Citrobacter freundii is characterized by various opportunistic infections including a variety of nosocomial infections of the respiratory tract, blood, urinary tract and other sterile sites in patients with suppressed immune system (MicrobeWiki, 2011).

Research has revealed that C. freundii is responsible for over 29% of all the opportunistic infections (Leboffe & Pierce, 2011). It is therefore