Escherichia

Escherichia coli secondary electron microscopy

Escherichia is a genus of Gram-negative rod-shaped bacteria of the family Enterobacteriaceae with active movement ( peritrichous flagella ) or unbegeißelt without active movement. Was named the genus after the German pediatrician Theodor Escherich. The genus Escherichia, is oxidase negative, shows, in contrast to the very similar genus Enterobacter, in the Voges - Proskauer reaction negative. The most important representative Escherichia coli.

Metabolism

The members of the genus Escherichia are chemoorganotroph, that is, they build to generate energy from organic substances. They are facultative anaerobes: If oxygen is present, they have an oxidative energy metabolism, they oxidize the organic matter to carbon dioxide (CO2 ) and water; when no oxygen is present, so under anoxic conditions, they use the mixed acid fermentation as Energiestoffwechselweg, with large amounts of acids (acetic acid, lactic acid and succinic acid ) are produced as end products.

Other genera of the family Enterobacteriaceae, such as Enterobacter, use under anoxic conditions, the 2,3- Butandiolgärung for energy. This produces as final products, especially in large amounts of alcohol 2,3- butanediol and CO2, next only in small quantities, inter alia, various acids. 2,3- Butandiolgärung is detected by the Voges - Proskauer test for acetoin, an intermediate product of this fermentation. This test is used to distinguish the Butanolgärung of the mixed acid fermentation and thus for the differentiation of Enterobacteriaceae.

Species

• E. albertii Huys et al. 2003
• E. blattae Burgess et al. 1973
• E. coli ( Migula 1895) Castellani & Chalmers 1919
• E. fergusonii Farmer et al. 1985
• E. hermannii Brenner et al. 1983
• E. senegalensis
• E. vulneris Brenner et al. 1983
• E. sp. ( Various )