Researchers Hone in on Bacteria Genome to Isolate Pathogens

By Laurie Greene, Founding Editor

Food safety is paramount in the specialty crop farm industry; but when a bacterium causes a food safety problem, there is important work to determine the exact fingerprint of that bacteria.

Matthew Stasiewicz, assistant professor of applied food microbiology in the area of food safety at the University of Illinois at Urbana-Champaign, Department of Food Science & Human Nutrition, said it’s important to determine the genome of these bacteria that are causing problems.

“The biggest thing that has happened in the field of food safety is that the U.S. government has committed to using whole genome sequencing as a primary public health surveillance tool. So, if you have a foodborne disease and go to a doctor, and they isolate that organism, it will go into a nationwide database—now international database—that can link that organism’s genome sequence to whatever else shows up in the database. So, at the same time, if pathogens are isolated from foods potentially as part of an outbreak, those sequences can be [entered into the database] and [experts can] gather information from food sources as well as clinical patients. And that’s just a major tool.”

Stasiewicz said the genome is important because we need to know the true source of that bacteria. “The pathogens that can make you sick can be distributed in the environment.

“So just because you potentially got sick from eating food and maybe you got an E.coli O157:H7 infection in your hometown, even if someone else two towns away got the same infection with E.coli O157:H7, we don’t know if that’s related, even if you potentially ate the same food,” Stasiewicz said. “That could come from the soil in your town, your local grower, a local grower somewhere else, or from a common source, common grower, or common packer, and gotten you both sick. This genome sequence information allows us to make those links much more clearly.”

Stasiewicz said this is an important pioneering effort to reduce food safety illnesses. “Importantly, from the food standpoint,” Stasiewicz said, “we want that information so we can find that and eliminate it. No food processor wants to make anyone sick. No grower wants to make anyone sick. So, we need to identify those concerns.”