Student Research: Frances Buck

, Environmental Health Technology (Tech) - No longer offered, 1998
Faculty Advisor:

Microbial Source Tracking: The Use of a Single vs. a Double Restriction Enzyme


The objective of this study is to evaluate the use of a one enzyme versus two enzymes in microbial source tracking studies.

Both point source and non-point source pollution contribute to the microbial contamination of lakes, streams, rivers and reservoirs. Fecally contaminated water may carry and spread numerous human pathogens, and the majority of US waterbodies contain elevated levels of these microbial pathogens. The concept of indicator organisms was first introduced to detect site contamination without specifically testing for each pathogen. The presence of E. coli is used as an indicator of fecal contamination. While this method measures the extent of microbial pollution, it does not identify the original source(s) of contamination.

Microbial Source Tracking (MST) was developed to link contaminated sites to the specific sources of microbial pollution. We genetically fingerprinted over two 2000 E. coli isolated collected from humans and animals fecal samples. MST identifies the contributing source of fecal contamination by genetically matching site-isolates to source-isolates. This method allows for successful source tracking in the environment. At least two enzymes, Eco R1 and Pvu II, are necessary to distinguish the resident source-strains from transient strains.