Researchers at Kansas State University in Manhattan, KS, have developed a genetic test that could help the cattle industry more rapidly and accurately detect pathogenic Shiga toxin-producing E. coli O157:H7. Leading the project is Lance Noll, veterinary biomedical science graduate student; T.G. Nagaraja, university distinguished professor of diagnostic medicine and pathobiology, and Jianfa Bai, assistant professor in the KSU Veterinary Diagnostic Laboratory. To develop the diagnostic test, Noll and Nagaraja worked with two KSU molecular biologists: Bai and Xiaorong Shi, research assistant of diagnostic medicine and pathobiology. The new test is a molecular assay, or polymerase chain reaction, that has been developed and validated to detect and quantify four genes specific for E. coli O157:H7. It detects bacteria based on genetic sequence, which Nagaraja calls the “bacteria’s fingerprints.” “The novelty of this test is that it targets four genes,” he said. “We are constantly working on finding better and more sensitive ways to detect these pathogens of E. coli in cattle feces.” The test is rapid, less labor-intensive and can be used in a diagnostic or research lab to accurately test many samples for E. coli. It can also be automated and help with quality control in cattle facilities. “Developing a method to detect E. coli before it can potentially contaminate the food supply benefits the beef industry by preventing costly recalls, but also benefits the consumer by ensuring the safety of the beef supply,” Noll said. The project is being funded by a U.S. Department of Agriculture Coordinated Agriculture Project grant.
