Pseudomonas aeruginosa is a rod-shaped Gram-negative aerobic bacterium belonging to the Pseudomonadadaceae family. Pseudomonas aeruginosa is a free-living bacterium commonly found in soil, water and occasionally on plant surfaces and normal animal flora (Todar, 2008). It acts as an opportunistic pathogen of humans and will infect almost any compromised tissue causing a variety of infections from urinary tract infections, bacteremia, and a variety of systemic infections; especially in those with a compromised immune system (Todar, 2008). Infections caused by Pseudomonas aeruginosa can be frustrating for doctors due to its resistance to antibiotics. Primarily a nosocomial pathogen, it is known to cause 10% of hospital-acquired infections (Todar, 2008). Pseudomonas aeruginosa is motile by means of a single polar flagellum used for adhesion and invasion during bacterial infection. Pseudomonas aeruginosa is ubiquitous in soil and water or on surfaces that come into contact with soil or water; as well as all artificial reservoirs. Its metabolism is always respiratory, but will grow in the absence of oxygen if nitrous oxide is available to function as a respiratory electron acceptor (Todar, 2008). Its most favorable temperature for growth is thirty-seven degrees Celsius, but it can grow up to forty-two degrees (Medscape, 2009). In nature, Pseudomonas is a vigorous bacterium that swims quickly due to its flagellum (Medscape, 2009). It has very simple nutritional requirements, making it easy to thrive almost anywhere. No organic growth factors are required, however over seventy-five organic compounds can be used for growth (Todar, 2008). Pseudomonas aeruginosa is tolerant to many conditions... middle of paper ......the best way to treat an infection caused by Pseudomonas aeruginosa, but it cannot always be prevented. Most strains are sensitive to gentamicin, tobramycin, and fluoroquinolines, but resistant strains have emerged that make treatment virtually impossible (Todar, 2008). Works CitedBlackwell, Timothy S and Christman, John W. and Prince, Alice S. and Sadikot, Ruxana T. (2005). American Journal of Respiratory and Critical Care Medicine. In pathogen-host interactions in Pseudamonas pneumonia. Retrieved October 18, 2011, from http://ajrccm.atsjournals.org/cgi/content/short/171/11/1209 Todar, Kenneth PhD., Textbook of Bacteriology. Wisconsin: University of Wisconsin, 2008.Medscape. (December 9, 2009). Drugs, diseases and procedures. In Pseudomonas aeruginosa infections. Retrieved October 30, 2011, from http://emedicine.medscape.com.