) is a gram-negative
bacterium. Some strains are pathogenic, others do not cause disease.
On the one hand, E. coli
is part of the healthy human intestinal flora. One the other hand, it can cause inflammation if translocated to other body parts. Moreover, there are pathogenic strains, which are a common cause for infectious diseases. Concerning molecular biology and genetics, this bacterium is the best researched organism. It is frequently used as a model organism in laboratories.