An ISU researcher has recently partnered with a local company to develop new ways to improve food safety.

Byron Brehm-Stecher, associate professor in food science and human nutrition, has collaborated with the Ames-based Advanced Analytical Technologies to create a cheaper method to perform multi locus variable number tandem repeat analysis. He has partnered with them before.

“In one of our discussions, they talked about the critical need for a relatively inexpensive, yet robust system for MLVA analysis and how they were well-positioned to fill this need,” Brehm-Stecher said.

MLVA is a method of “fingerprinting” individual strains of an organism based on differences in their DNA. During an outbreak of a food-borne pathogen such as salmonella typhimurium, it is important to be able to distinguish different strains of the bacteria from each other.

This helps epidemiologists trace the outbreak back to its source, which allows them to inform the consumers and recall products that are making people sick.

Ruth MacDonald, professor and chairwoman of the food science and human nutrition department, said identifying pathogens is vital during an outbreak.

“You can say, ‘this pathogen in these people is the same as the pathogen that was found on this equipment in that farm — or on that production line.’ It’s like fingerprints,” MacDonald said.

The current method for this DNA fingerprinting process is pulsed field gel electrophoresis. It is a well-established procedure, but it is time consuming and does not have the advantages of MLVA, which can distinguish very closely related microbes from one another.

Brehm-Stecher said MLVA is seen as the successor to the electrophoresis, but one major drawback is that the existing instruments for the technique, DNA sequencers, cost more than $100,000.

Because the analysis is expensive, many state labs wait until they have received enough samples from the field to justify an analysis. This can take as long as a month. During that time, people are still getting sick from contaminated food.

“If a common, low-cost instrument capable of rapid data collection and digital data sharing were available, this could unlock the potential for use of MLVA by not only State Health Labs and the CDC, [Centers for Disease Control,] but also by smaller labs, which could feed into the same data sharing networks and act as additional sentries for earlier outbreak reporting,” Brehm-Stecher said.

Hyun Jung Kim, molecular biologist and postdoctoral research associate at Iowa State, was a key intermediary between Iowa State and Advanced Analytical, Brehm-Stecher said.

Together, they and representatives of Advanced Analytical presented their research at the American Society for Microbiology’s General Meeting in May.

Their next step is to develop an MLVA system for commercial use. Their market includes the CDC, state health labs, and other government agencies and hospitals.