Definition: A family of aerobic, facultatively anaerobic, nonsporeforming bacteria (order Eubacteriales) containing gram-negative rods. Some species are nonmotile, and nonmotile variants of motile species occur; the motile cells are peritrichous. These organisms grow well on artificial media. They reduce nitrates to nitrites and use glucose fermentatively with the production of acid or acid and gas. Indophenol oxidase is not produced by these organisms. They do not liquefy alginate, and pectate is liquefied only by members of one genus, Pectobacterium. This family includes many animal parasites and some plant parasites causing blights, galls, and soft rots. Some of these organisms occur as saprophytes that decompose carbohydrate-containing plant materials. The type genus is Escherichia.