Step 7: Ribotyping of isolates.
UNH Jackson Estuarine Lab receives our E. coli isolates, confirms that they are indeed E. coli through a series of biochemical tests, and then conducts a genetic analysis called ribotyping. This process examines the rRNA genetic material in each bacterial isolate and produces an image of a banding pattern. This image is used classify the E. coli by strains, and is the basis for comparison of unknown sources to known sources. Below is a photo of ribotypes from deer scat (which are uniform) and from water sample (variable). The arrows indicate a match between a deer source sample and an unknown source sample. Beside the photo is an outline of the ribotyping process. Contact Dr. Steve Jones at UNH Jackson Estuarine Lab for more information on this phase of the project.

Ribotyping Lab Procedure DNA extracted & purified. DNA digested w/restriction enzyme. DNA separated via gel electrophoresis. DNA denatured & blotted onto membrane. Hybridization with E. coli rRNA DNA probe. DNA exposed to a chemiluminescent substrate & digitally imaged. Image enhanced & optimized in computer.

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