Rapid Micro Rolls On

Life Technologies recently focused on strain typing, which it believes will be useful in tracing the origin of contaminants. Currently, pulse-field gel electrophoresis is used to type strains when there is an outbreak. Life Technologies is studying the roughly 20 existing sequenced strains of Salmonella, while using its own solid sequencing technology to sequence another 40 strains in house.

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RapidFinder Express Software displays results of a food pathogen detection test in an intuitive, easy-to-read format with presence/absence calls.

“The idea is to use all this information to come up with a single nucleotide polymorphism (SNP)-based or sequence-based genotyping format that would be faster and more accurate than current pulse-field gel electrophoresis,” Dr. Furtado said. “The general hypothesis is to collect enough data to come up with certain gene sets or SNP sets that will be able to specify the strain type,” he said, adding that it may be another six to eight months before the company comes up with defined SNP signature patterns. “Then we’ll need to test it with a large number of strains to make sure it works,” he said.

Higher Standards

The Association of Official Analytical Chemists (AOAC) Research Institute validated the MicroSEQ Listeria monocytogenes detection kit, and Life Technologies plans to submit its other key products for validation, which the company said will help assure food manufacturers that they are using effective methods. “We’re putting the full portfolio of high-volume pathogen tests out this year and seeking validation through the AOAC,” said Schwartz.

Congress, which is also working to improve food safety, is now considering the Food Safety Enhancement Act. “We expect it will set standards for more testing and production and food safety in plants that didn’t have it before,” Schwartz said. “It will be good for food safety.” ■

Valigra is a science journalist based in Cambridge, Mass. Contact her at [email protected].