A group of Gram-negative rod-shaped bacteria that are found in the vertebrate gastrointestinal tract; their presence in water is an indicator of faecal pollution. They obtain their energy by aerobic respiration or fermentation; some of them can ferment lactose. Well-known coliform bacteria include Escherichia coli and Salmonella.
Geology and Earth Sciences
Rod-shaped, Gram-negative bacteria that occur widely in soil, on vegetation, and in water. They are abundant in the faeces of birds and mammals.