Bacterial colonies can differ greatly in their morphologies.These differences can help us in identifying different species of bacteria. Likewise, bacterial species differ in their cellular morphologies and staining properties. Again, these differences can be used to aid in identifying different species.To aid in the more definitive identification of bacteria, microbiologists have developed a series of biochemical tests that can be used to differentiate even closely related organisms.These various tests were designed to identify various metabolic properties of different bacterial species these differences in carbohydrate metabolism, protein metabolism, fat metabolism, production of certain enzymes, ability to utilize a particular compound etc. help them to be identified by the biochemical tests. The identification of higher plants and animals involves the observations of the structural differences, both internal and external, which exist among them. Most of these structural differences are visible to naked eye. Even the identification of microscopic plants and animals involves the observations of their structural differences under a microscope.Such identification based on structural differences is not possible in case of bacteria, because structural differences, which may differentiate one species of bacteria from the other, are not discernible even under a microscope.The structural differences with respect to shape, size and arrangement of bacteria only help in the process of identification, because there are many species of bacteria having similar shape, size and arrangement.Therefore, ultimately, the identification of bacteria is mostly based on the differences in their biochemical activities.

DOCTER is a specialised database containing information about the species of bacterial family Enterobacteriaceae. It contains information about biochemical tests for species of enterobacteriaceae. The current Database contains information about 11 genus and 112 species of family enterobacteriaceae which includes general details such as classification,syonyms,genbank id.,habitat,pathogenicity and biochemical test results of species. It contains a query section which provides three different modes to access the information in this database.Database can be used to compare,identify or to confirm bacterial species.