Scientific Breakthrough Prevents E. coli From Surviving In Cattle

Posted on May 27, 2010 by Shawn Stevens

In the continuing battle to prevent naturally occurring microorganisms like E. coli O157:H7 from growing in cattle, researchers have discovered some promising new tools.

Although E. coli O157:H7 can cause illness in humans, the bacteria often exists as part of the gastrointestinal flora in healthy cattle. In turn, microbiologists at the University of Texas (“UT”), Southwestern Medical Center, working with the USDA, uncovered a mechanism which actually prevents E. coli O157:H7 from surviving in grain-fed cattle.

E. coli O157:H7 harbors a gene called sdiA, which makes the SdiA protein. When traveling within a cattle’s body, the SdiA protein senses a chemical made by microbes in the animal's rumen, the first of a cow's four stomachs, which serves as a large fermentation chamber.

Only after detecting this signal will the bacteria pass through the rumen and colonize in the recto-anal junction. By interfering with the SdiA protein (or, the genetic sensor), however, researchers were able to stop the bacteria from ever reaching the required colonization site. Notably, rather than colonizing, the bacteria simply died off, preventing any potential for future shedding or contamination.

"We're diminishing colonization by not letting pathogen go where it needs to go," said Dr. Vanessa Sperandio, associate professor of microbiology and biochemistry at UT Southwestern and senior author of the study. "If we can find a way to prevent these bacteria from ever colonizing in cattle, it's possible that we can have a real impact on human disease.” Notably, “[t]his could be something as simple as including some sort of antagonist in cattle feed, which would result in less shedding of the bacteria and less contamination down the road."

The findings, of course, are important because an estimated 70 percent to 80 percent of cattle herds can carry these pathogens. According to Dr. Sperandio, the finding “serves as a proof-of-principle that we might be able to target this system and help prevent food contamination."

Tags: , , , , , , , , , , , , , , ,

Salmonella Concerns Prompt Recall Of Various Milk Products

Posted on June 29, 2009 by Shawn Stevens

According to the FDA, the Plainview Milk Products Cooperative has announced a voluntary recall of various milk products following the discovery of potential Salmonella contamination. The recall includes all instant nonfat dried milk, whey protein, fruit stabilizers, and gums (thickening agents) produced by the company during the past two years at its facility in Plainview, Minnesota. Click on the following link to view a copy of the FDA News Release.

The investigation which led to the recall is an interesting example of the ways in which the governmental agencies, which oversee the food industry, can and do work together to identify any potential problems which may arise. The investigation began when the USDA found Salmonella in 100-gram pouches of Dairyshake powder that were not for retail sale. The USDA then alerted the FDA, who later discovered salmonella on some of the processing equipment used in the Plainview plant. The FDA conducted the investigation in collaboration with USDA, CDC, the Minnesota Department of Agriculture, and various state and local health departments.

The products which were voluntarily recalled have not been linked to any illnesses, nor did they reach consumers directly. Rather, they were sold to other downstream companies, which then used the ingredients to process other foods.

We will, of course, continue to report on continuing developments.

Tags: , , , , , , , , , , , , , , , , , , ,