MODIFIED SCHEME FOR IDENTIFICATION OF COLIFORM ORGANISMS IN DRINKING-WATER

A total of 370 coliform strains isolated from 950 drinking water samples were typed and characterized on the basis of 32 tests. Most of the types as per the scheme of Wilson et al (1935) contained organisms belonging to more than one species or even genus, some of which were quite unrelated having different GC contents. To overcome this limitation, the scheme of Wilson et al has been modified in this study by replacing the gelatin liquefaction test with the motility test. Using the new scheme most of the coliform organisms could be identified up to species level in much less time.