Escherichia coli

Gram-negative bacillus found in the colon. As part of the intestinal flora it supports physiological tasks such as vitamin synthesis. Outside the colon, this bacterium may trigger urinary tract infection, inflammation of the stomach or meningitis in neonates. Several strains cause intestinal diseases, for example, Travellers' Diarrhoea.

E. coli serves as test organism for efficacy testing of disinfectants and as indicator of faecal contamination of water.