Definition of Pathogenicity island
Pathogenicity island: The genetic element, the "island of evil", within the genome of an organism that is responsible for its capacity to cause disease (its pathogenicity). The virulence of the organism is modulated by genes harbored on this island.
For example, enterococci are part of the normal bacterial flora of the intestine but are also notorious causes of nosocomial (hospital-acquired) infections highly resistant to antibiotics. The virulence determinants of enterococci have been found clustered on a large pathogenicity island.Source: MedTerms™ Medical Dictionary
Last Editorial Review: 6/14/2012