The genus Enterobacter belongs to the family Enterobacteriaceae. Members of the genus Enterobacter are Gram-negative, oxidase-negative, straight rod-shaped bacteria. They are facultatively anaerobic, chemoorganoheterotrophic and exhibit a respiratory and fermentative metabolism. Enterobacter species are catalase-positive, reduce nitrate to nitrite, produce enterobacterial common antigen, produce acid from D-glucose, D-mannitol, salicin, L-arabinose, L-rhamnose, D-xylose, trehalose, D-cellobiose and maltose; hydrolyze o-nitrophenyl-ß-D-galactosidase. They oxidize D-glucose to D-gluconate in the presence of pyrrolochinoline quinone, they produce gas from glucose. Most strains utilizes: N-acetyl-D-glucosamine, D-alanine, L-alanine, L-arabinose, L-aspartate, D-cellobiose, citrate, D-fructose, D-galactose, D-galacturonate, gentiobiose, D-gluconate, D-glucosamine, D-glucose, D-glucuronate, L-glutamate, DL-glycerate, glycerol, 2-ketogluconate, DL-lactate, lactose, maltose, maltotriose, D-mannitol, D-mannose, 1-O-methyl-ß-D-galactoside, 1-O-methyl-?-D-glucoside, L-rhamnose, D-ribose, L-serine, succinate, D-trehalose, D-xylose. Most Enterobacter species are negative for the following tests: H2S production from thiosulfate, phenylalanine deaminase, tetrathionate reduction, tributyrin or corn oil hydrolysis, ß-glucuronidase, 2-ketogluconate-dehydrogenase.