We processed 50 urine samples out of these 15 isolates were confirmed as E.coli. On the Luria Bertani agar plates the colonies were gram negative because it had taken pink stain (i.e. counterstain) and occur Gram negative rods under microscope i.e. Escherichia coli.
All the isolates of E.coli had given positive test for the indole, methyl-red, catalase test; there weconfirmed that these organisms are E.coli