PEORIA —The most famous discovery at Peoria's federal research laboratory forever changed healthcare: the development of a method to mass produce penicillin put life-saving medicine into the hands of millions.

Decades later, scientists at the National Center for Agricultural Utilization Research have discovered a way to amplify the effectiveness of that most basic front-line treatment for infection, while at the same time overcoming the worst side effect of the long-term success of antibiotics.

In preliminary testing, minute doses of a derivative of a naturally occurring material, tunicamycin, enhanced the efficacy of antibiotics by two to 250 times. And that derivative overcame bacteria that have grown immune to some antibiotics over decades of treatment.

The derivative potentially represents a new avenue to treat antibiotic-resistant strains of bacteria with much smaller doses of drugs and opens the door to using antibiotics that have long been shelved because they are not effective against modern microbes.

"Potentially, you'd have new combination drugs, so some of those older penicillins can be used again," said microbiologist Neil Price. "Most penicillins aren't used anymore because of the resistance that has developed to them."

Tunicamycin itself has been widely used as a scientific tool since its discovery in Japan in the 1970s, and it also is a potent antibiotic — too potent. It is so strong that it does not discriminate between bacterial and other cells, it kills them all.

"The tunicamycin itself is very toxic, that's the problem with it," Price said.

Added fellow microbiologist Chris Skory: "It's an antibiotic in high enough doses, but that doesn't matter because of its toxicity."

But experimentation at the ag lab with derivatives synthesized from the substance, which can be found naturally occurring in soils all over the world, showed promising results with the reduction of one double bond. The resulting compound killed bacteria in a lab sample — it had a "good kill zone," Price said — but spared other cells.

And it worked with extremely small amounts. The scientists initially synthesized a few grams of the substance, but found it effective with doses less than one half of a microgram. With its multiplying effect on other antibiotics, combination drugs could be given in much smaller amounts.

"We've essentially done away with the toxicity issue, and you're ending up with a very small amount of material that you're ingesting," Price said.

Matt Buedel can be reached at 686-3154 or mbuedel@pjstar.com. Follow him on Twitter @JournoBuedel.