Pseudomonas aeruginosa is a rod-shaped, Gram-negative aerobic bacterium belonging to the Pseudomonadadaceae family. Pseudomonas aeruginosa is a free-living bacteria commonly found in soil, water and occasionally on plant surfaces and in the normal flora of animals (Todar, 2008). It acts as an opportunistic pathogen in humans and infects almost all compromised tissues, causing a range of infections such as urinary tract infections, bacteremia, and various systemic infections; especially in those with weakened immune systems (Todar, 2008). Infections caused by Pseudomonas aeruginosa can be frustrating for clinicians due to its antibiotic resistance. Primarily a nosocomial pathogen, it is known to cause ten percent of nosocomial infections (Todar, 2008). Pseudomonas aeruginosa is motile by means of a unique polar flagellum used for adhesion and invasion during bacterial infection. Pseudomonas aeruginosa is ubiquitous in soil and water or in surfaces in contact with soil or water; as well as all artificial reservoirs. Its metabolism is still respiratory, but it will develop 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 at temperatures up to forty-two degrees (Medscape, 2009). In nature, Pseudomonas is a robust, fast-swimming bacterium due to its flagellum (Medscape, 2009). Its nutritional requirements are very simple, allowing it to easily thrive almost anywhere. Organic growth factors are not necessary, but they can use over seventy-five organic compounds 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 avoided. Most strains are sensitive to gentamicin, tobramycin, and fluoroquinolines, but resistant strands have emerged, making treatment virtually impossible (Todar, 2008). Works Cited Blackwell, 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. Accessed 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). Medicines, diseases and procedures. In Pseudomonas aeruginosa infections. Retrieved October 30, 2011 from http://emedicine.medscape.com.