UNIVERSITY PARK, Pa. — With its 50-year-old E. coli Reference Center, Penn State long has been at the forefront in isolating bacteria from animals, humans and the environment. The University will continue its leading role Nov. 6-8 when it hosts an international group of experts to propose how to transition one of the most fundamental tests for E. coli into a genomics-based assay.
Ed Dudley, associate professor of food science in the College of Agricultural Sciences and a well-known E. coli researcher, will host the closed workshop, which will involve scientists from nine countries.
The need for the workshop is both straightforward and complicated, Dudley explained. One of the most common tests to perform when isolating E. coli from animals, humans or the environment is called serotyping. The Penn State E. coli Reference Center — the world's largest E. coli collection of isolates that have come from food and animals — is one of just a handful of places in the world where this test is done routinely.
According to Dudley, the center typically conducts 2,500-3,500 of these tests every year for clients worldwide in academia, government and industry.
"The test has existed since the 1940s and currently is based upon identification of surface structures called the lipopolysaccharide, and flagella using antibodies," he said. "Owing to the fact that DNA sequencing is becoming dirt-cheap, several ways have been proposed to convert the current assay to a molecular one.
"While this sounds good, we have learned it won't be that easy and that researchers will need to come to a consensus on several issues, including how to define a 'new' type, and what naming designations to use when the new method doesn't agree with the traditional method."
Dudley noted that scientists at Penn State and around the world are discovering, through DNA sequencing, new serotypes of E. coli, but there is insufficient agreement for how to get these new types approved by the international community.
"We hope the workshop here can lead to a consensus," he said. "The international panel will write a proposal for the rest of the global community — providing guidelines for replacing the 80-year-old method of serotyping with something better — and in the process change the way we do this crucial analytical technique for the best-studied bacterium on the planet."
This is an exciting time for hosting this workshop, Dudley noted, with the E. coli Reference Center moving from the Department of Veterinary and Biomedical Sciences to its new home in the Department of Food Science.
Among those scheduled to attend the workshop, which is being funded by Janssen Vaccines and the College of Agricultural Sciences' Office for Research and Graduate Education, are several top experts in the field:
— Flemming Scheutz, head of the World Health Organization Collaborating Center for Reference and Research on Escherichia coli and Klebsiella, Denmark
— Linda Chui, molecular program leader, Provincial Laboratory for Public Health, University of Alberta, Canada
— Atshushi Iguchi, associate professor, Faculty of Agriculture, University of Miyazaki, Japan
— Stefano Morabito, senior scientist and deputy director, European Union Reference Laboratory for E. coli Veterinary Public Health and Food Safety Departments, Istituto Superiore di Sanitá, Italy
— Claire Jenkins, head of E. coli Reference Services, Public Health, England
— Angelika Fruth, National Reference Center for Salmonella and Other Enteric Pathogens, Robert Koch Institute, Germany
— Sara Christianson, head of Reference Services Lab, Public Health Agency, Canada
— Patrick Fach, senior research scientist, Laboratory for Food Safety, French Agency for Food, Environment, and Occupational Health and Safety, France
— Sabine Delannoy, research scientist, Laboratory for Food Safety, French Agency for Food, Environment, and Occupational Health and Safety, France
— Adrian Cookson, senior scientist, AgResearch, Hamilton, New Zealand
— Peter Reeves, professor of microbiology, University of Sydney, Australia
— Eleven scientists from the U.S. Food and Drug Administration, Penn State and other American academic institutions, the U.S. Department of Agriculture, and the U.S. Centers for Disease Control and Prevention