Applied Microbiology and Biotechnology

, Volume 63, Issue 2, pp 231–238

A biomarker for the identification of swine fecal pollution in water, using the STII toxin gene from enterotoxigenic Escherichia coli

Short Contribution

DOI: 10.1007/s00253-003-1373-9

Cite this article as:
Khatib, L.A., Tsai, Y.L. & Olson, B.H. Appl Microbiol Biotechnol (2003) 63: 231. doi:10.1007/s00253-003-1373-9


This research developed a PCR method to identify swine fecal pollution in water, using a portion of the STII toxin gene from enterotoxigenic Escherichia coli as the target sequence. This method showed the gene to have a wide-spread geographical distribution and temporal stability; and the primers demonstrated high specificity, sensitivity, and reliability. A total of 110 DNA extracts from different animal fecal and human sewage samples were screened using the primers and no positives resulted. Centrifugation and filtration methods for concentrating E. coli seeded into stream, ocean, secondary effluent, and dairy lagoon waters resulted in detection limits at the femtogram and attogram levels. E. coli with the biomarker seeded into stream, ocean, and secondary effluent waters remained stable for approximately 2 weeks for all water types. Of the farm lagoon and waste samples tested, 94% were positive for the STII trait, regardless of the number of E. coli screened and 100% were positive when ≥35 E. coli isolates were screened. As the PCR product of the target sequence yielded a single band, the method is applicable to dot blot detection methodology, yielding great accuracy in determining the presence of swine fecal sources.

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  1. 1.Department of Environmental Health Science and PolicyUniversity of California at IrvineIrvineUSA